Document zzeXZeoj3Moxpzog80qzg7Ywn

August 6, 1985 A INCORPORATED 100 NORTH CENTRAL EXPRESSWAY SUITE 600 RICHARDSON. TEXAS 75080 (214) 234-8567 It was pleasant meeting you and having the opportunity. to have you in our works hop. I've taken the liberty of enclosing a brief description of our firm, a description of our TRPUF model, and a revised attendance list. Enclosed is an evaluation sheet. Could you please fill it out and return it to us in the enclosed envelope? As I emphasized in the course, if you have any questions concerning toxic gas releases, please don't hesitate to call me or a member of our staff. Sincerely, RHS/pgl/C1201579 Enclosures i VAB.0001126427 PRACTICAL PLANNING FOR TOXIC GAS RELEASES REGISTRATION LIST Houston, TX - July 31, 1985 Mr. Allen Jurisich Senior Program Advisor, Environmental Service Cigna Loss Control 139 West Livingston Place Metairie, LA 70005 (504) 831-1617 Mr* John Brau Employee Relations Manager Sohio Chemical Company Box 659 Port Lavaca, TX 77979 (512)552-8218 Mr* Joe Ledvina Director of Environmental Activities Vista Chemical Company P.0. Box 19029 Houston, TX 77224 (713)531-3451 Ms. Aillean Teng Senior Environmental Health Specialist Cigna Loss Control Service 12815 Leader Houston, TX 77072 (713)933-1826 Mr. Ron Pertuit Texas Eastman Company P.0. Box 7444 Longview, TX 75607 (214) 236-5000 ext. 2760 Mr. Joe Woolbert Texas Eastman Company P.0. Box 7444 Longview, TX 7 5607 (214) 236-5000 ext. 2760 TRINITY CONSULTANTS, INC. T A 001126428 Trinity Consultants, Inc. has specialized making estimates quality and in obtaining air pollution permits sincee 1974. All employees devote their time exclusively to this narrow area of the environmental ey are unusually familiar with rules, regulations, and practices. The client benefits imn terms of reduced costs and quick response ime As a firm employees and its own coi overhead is low and individuals working on study deal directly with the client niapprsion Moiling studies- These studies are performed to help clients evaluate the air quality either to pinpoint the sources of current problems or to evaluate the effect of proposed changes. Since 1978, Trinity Consultants has prepared over 300 dispersion modeling studies for clients in 40 states. Typical categories of work include: e Trinity Consultants is a leading firm in preparing "Prevention of Significant Deterioration" (PSD) applications. Since 1977, 115 PSD reports have been prepared for nearly every type of industrial plant. Applications have been prepared for plants located in all 10 EFA regions and in 29 states. e SIP Revisions - Since 1978 Trinity Consultants has helped 9 clients obtain permits to.construct in non-attainment areas. In 15 other cases Trinity Consultants has been involved in State Implementation Plan revisions. Stack Heights - Trinity Consultants has conducted more than a dozen studies of stack design to optimize investment. Training Seminars. Three courses are conducted: a two--day course on the fundamentals of dispersion modeling, a two-day laboratory applications course using dispersion models on an IBM-PC and a one-day seminar entitled "Permits Under the Clean Air Act". These courses have been taught a total of over 90 times and have been sponsored by professional associations for their members, major corporations for their employees and Trinity Consultants for the public. Sale of Models and Met Data. Clients can purchase dispersion models and meteorological data in one of 3 ways: First, 21 firms currently use Trinity Consultants timesharing service devoted almost exclusively to air quality dispersion models. Second, over 70 customers have purchased IBM-PC versions of popular air pollution dispersion models. Third, since 1976 some 20 firms have purchased IBM mainframe version of the UNAMAP models. Trinity Consultants also processes and sells meteorological data from its extensive library. Delivery is generally overnight TOXIC Q&S, Reims? 20 firms have been served with studies of the possible effects of a potential gas releases, estimated effects of actual releases, building ventilation studies and testimony in court. Both puff models and steady state models have been used in these analyses. January 1, 1985 214/234-8567 TRINITY CONSULTANTS, INC Atf001126429 Firms PARTIAL LIST OF CLIENTS A Allied Materials Corp. 4 American Petrofina, Inc. Calumet Refining Co. Inc. + Champlin Petroleum, Inc. * Crystal Oil Company Dorchester Refining Company Getty Refining & Marketing Co. 4 Gulf Oil Co. - U.S. Kerr-McGee Corp. Lake Charles Refining Co. 4 Murphy Oil Corp. + Pennzoil Oil Corp. Plateau Refining Co. Rock Island Refining * Sigmor Refining Co. + Standard Oil Co. (Indiana)(AMOCO) Standard Oil Co. (Ohio) + Sun Company Union Oil Company * Vidette Refining Co. + Aminoil U.S.A., Inc. Arco Oil & Gas Co. Mid-American Oil & Gas (Centex) Cities Service Company Delhi Gas Pipeline Co. + Endevco, Inc. Exxon Production Research + Farmland Industries + Getty Oil Co. Haliburton Resource Management * Runt Energy Co. Husky Oil Co. + Kerr--McGee Corp. Koch Hydrocarbon Co. Leede Oil & Gas Inc. Mesa Petroleum Co. Moore McCormick Energy + Pursue Gas Processing 4 Shell Oil Co. * Sun Exploration & Production Texas Oil & Gas Corp. Tipperary Corp. * Tomlinson Interests * Union Texas Petroleum 4 Boise-Cascade 4 Bovater Southern Paper Corp. Celotex Container Corporation of America 4 Fort Howard Paper Co. Georgia-Pacific * Ham&ermi 11 Paper 4 Owens-Illinois, Inc. Temple Eastex, Inc. 4 Airco Carbon 4 Firestone Synthetic Rubber & Latex 4 Agrico, Inc. 4 Freeport Chemical Co. 4 American Cyaminid Georgia Pacific Co. 4 CF Industries, Inc. 4 Goodyear Tire & Rubber Co. Cabot Corp 4 V.R. Grace (Davidson Chemical Div.) Calgon Corporation 4 Kerr-McGee Chemicals Chemische fferke Huls AG + Chevron Chemical Co. Mississippi Chemical Corp. 4 Monsanto Corp. Colombian Chemical Co. Olin Chemical Conoco Chemical Co. Petro United, Inc. Cosden Oil -- Chemical Co. Procter & Gamble Co. Coulton Chemical Co. Rohm & Haas, Inc. 4 Dow Chemical Co. Sintech, Inc. 4 E. I. DuPont de Nemours Stauffer Chemical 4 Ethyl Corp. Sid Richardson Carbon & Gasoline FMC Corporation 4 Union Carbide Corp. . Vulcan Chemical Co. TRINITY CONSULTANTS, INC. 01126430 n-i i mp w-' Energy Fuels Nuclear, Kerr-McGee Corp. Texas Industries + Pittston Coal * Sobio Arco Aluminum Blaw-Knox Chaparral Steel (TXI) Kaiser Aluminu: & Chemical Corp LTV Steel National Steel * National Zinc +* NL Industries + RSR Corporation * Ross Metals Consultants Argento, Vittorio Benham Group, Inc Louis Berger & Assoc, Bovay Engineers, Inc. Breisch Engineering Co. Browning-Ferris Industries Caste1 Consulting Service CE-Maguire George R. Alexander, Jr. Baker & Daniels Greenberg, Traurig Lynberg & Nelson Millbank, Tweed Popham, Haik, Schnobrick, Kaufman & Doty Rooks, Fitts & Poust Chittenden Engineering Co. Clark, Dietz & Associates Sewell, Junell & Riggs + Thompson & Knight Controls for Environmental Pollution Wachtell, Lipton, Rosen & Katz Cooper Engineers Daniel Construction Co. Davis & Floyd Engineers, Inc. Cement. Stone. Lime & Glass Evergreen Environmental Management F.E. Courtney & Associates Acme Brick Ford, Bacon & Davis Gibbs and Eill Kaiser Engineers George E. McVehil MITRE B.L. Anderson + Capitol Aggregates, +* Chemical Lime * Centex Corp. Dal-Tex Cement Inc. Metro Environmental Application Moore Engineering J.F. Mullen & Associates Ortloff Corp. Petro Project Engineering, Inc. Petrochem Consultants, Inc* R.W. Beck & Associates Resource Consultants, Inc. Rist, Frost Associates Scott Environmental Simons Eastern Stanley Consultants Steuver & Associates + J.E. Thibault & Associates Tippet & Gee Trovillion, A1 TRW, Inc. Englehard Minerals & Chemicals General Portland, Inc. Genstar Building Materials Co. Gifford Eill Portland Cement Ideal Basic Industries Lehigh Portland Cement Libbey-Owens-Ford Lone Star Cement Loomis Construction Nevada Cement Owens-Corning Owens-Illinois, Inc. Southwestern Portland Cement + Texas Industries, Inc. U.S. Brick + U.S. Gypsum + Turner Engineering Turner, Mason & Associates Roy F. Weston Co. A TRINITY CONSULTANTS, INC. VftK0001126431 * Arizona Public Service, Inc. * Brazos Electric Power Cooperative +* Cajun Electric Power Cooperative Foothills Pipeline, Ltd. * Golden Valley Electrical Co-op, Inc +* General Electric Co. + Hawaiian Electric Company Louisiana Power & Light Mississippi River Transmission Corp * Nebraska Power & Light New Orleans Public Service, Inc. + Panhandle Eastern Pipeline * Oklahoma Gas & Electric Co. + Southwestern Electric Power Co. Tennessee Gas Transmission Co. Transcontinental Gas Pipeline Co. * United Gas Pipeline, Inc. * Valley View Energy Alexander & Baldwin Amstar Corp. Bunge Corp. * City of Detroit Dresser Industries Ford Motor Co. (Boiler) + Frito Lay, Inc. Gearhart Industries City of Indianapolis + Intec, Inc. * Iowa Beef Processors Manville Building Corp. McDonnell-Douglas Corp. * City of San Diego TD Mechanical Texas Instruments * University of Vermont Varo, Inc. * Warwick, Rhode Island States in Which Studies Have Been Done Alabama Alaska Arkansas California Colorado Connecticut Florida Georgia Hawaii Illinois Indiana Iowa Kansas Kentucky Louisiana Maine Maryland Michigan Mississippi Missouri Montana Nebraska New Jersey New Mexico Nevada North Dakota Ohio Oklahoma Pennsylvania Puerto Rico Rhode Island South Carolina Tennessee Texas Utah Vermont Virginia West Virginia Wisconsin Wyoming Countries in Which Studies Rave Been Done Brazil New Zealand Belgium Netherlands Canada Saudi Arabia Gulf of Mexico Indonesia Firms Purchasing Specialized Tra ning Programs/Seminars Air Pollution Control Association American Cyanimid American Society of Mechanical Engineers Aramco Services Company Ashland Chemical City of Indianapolis Damson Oil IBM Inland Steel Co. Kerr-McGee Corp. * Served through a consulting firm + Performed more than one study Mobi1 Oil PEDCO Environmental Republic Steel Standard Oil Co. (Indiana)(AMOCO) Tennessee, State of Texas Chemical Council Timken Company U.S.Environmental Protection Agency Regions IV and VII United Technologies University of Texas (for EPA) January 1, 1985 (84-62) TRINITY CONSULTANTS, INC 4 XA 1126432 i EMPLOYEE QUALIFICATIONS Richard H. Schulze President Mr. Schulze received a BSE degree in Mechanical Engineering from Princeton University in 1954 and a MBA degree from Northwestern University in 1958. Following .13 years of work in corporate long-range planning and product development, he joined Core Laboratories Inc. in 1971 as President of their environmental affiliate. Ecology Audits, Inc. He supervised activities in stack sampling, ambient air monitoring networks, water quality studies and preparation of environmental impact statements. In 1974, he founded Trinity Consultants, a firm responsible for over 300 dispersion modeling studies including over 115 PSD permits and 15 SIP revisions. In 1975 he started teaching a two-day short course on dispersion modeling. To date, there are over 1000 graduates of this course which has been offered 80 times throughout the world. Since 1978 he has taught all the Air Pollution Control Association (APCA) short courses dealing with the fundamentals of dispersion modeling as well as selected EPA courses. He is a registered Professional Engineer, a Diplomate of the American Academy of Environmental Engineers, the founder of the North Texas Chapter of APCA, the author of numerous papers on air pollution, and a member of more than 10 professional organizations. He is the sole owner of Trinity Consultants, Inc. James C. Clary, Jr. Project Manager # Mr. Clary has over 10 years experience in work as a consulting meteorologist. He holds both the BS and MS degrees in Meteorology from Florida State University. After completing his active military obligation as an officer, Mr. Clary joined Dames & Moore Consultants where he worked on meteorological and safety studies for nuclear power plants as well as on the dispersion of conventional pollutants, including preparation of several PSD permits* Mr. Clary has continued his work in meteorology since joining Trinity Consultants in 1978. He has served as project manager for over 28 PSD permit applications and over 50 other modeling studies. He is also the director of data processing and has installed two computer systems at Trinity. Mr. Clary has been responsible for converting most of EPA's UKAMAP models to be executable on IBM-PC or compatible computers and for developing a two-day Dispersion Modeling Laboratory course which he has now taught 6 times. Mr. Clary is a Certified Consulting Meteorologist of the American Meteorological Society. He taught a semester-length course on modeling of air pollutants at the University of Texas at Dallas. ...j p TRINITY CONSULTANTS, INC___________126433 Deborah K* Fusselman Project Manager Ms* Fusselman graduated cum laude in Chemical Engineering from Texas A&M University in 1980* After graduation, she joined Trinity Consultants and became involved with the development of emission inventories and the preparation of state and federal permit applications. Subsequently, her work also included over 70 dispersion modeling studies* More than half of these dispersion modeling studies were performed for state and federal permit applications* The majority of the permit applications have focused on petroleum refineries, chemical plants, natural gas processing plants and compressor stations* Ms* Fusselman has also assisted timesharing customers with the use of and with technical modeling advice* She has converted most UNAMAP models to execute on the IBM mainframes* She has satisfied the written requirements for registration as a Professional Engineer in the State of Texas* She is a member of the American Institute of Association* Chemical Engineers and the Air Pollution Control Tammy S* Rippetoe Project Meteorologist Ms* Rippetoe graduated cum laude in Meteorology from Texas A&M University in 1983* She joined Trinity Consultants in July, 1984, and has become involved in preparing emission inventories, dispersion modeling and processing meteorological data* She is a member of the American Meteorological Society and the Air Pollution Control Association* Scott R. Humphrey Project Meteorologist Mr. Humphrey graduated magna cum laude in Meteorology from Texas A&M in 1983 and received his Master of Science degree in Meteorology from Texas A&M in 1985* His graduate study was in the areas of atmospheric diffusion and boundary layer turbulence* He joined Trinity Consultants in March, 1985, and his duties include dispersion modeling, processing meteorological data, and aiding in the preparation of project reports* He is a member of the American Meteorological Society and the Air Pollution Control Association* TRINITY CONSULTANTS, INC. TRPUF TOUR SOLUTION FOR EVALUATING TOXIC GAS RELEASES INTRODUCTION Trinity Consultants, a leader in the field of IBM--PC applications for the air pollution professional, has developed a software package for evaluating releases of toxic gases. This package consists of both the EPA Puff model and TRPUF, a puff model developed by Trinity Consultants. TRPUF is based upon the EPA Puff model. A graphics system is also included in this package. System characteristics include: e Simple data entry using interactive and menu-driven screens e Complex input variables are not required e Graphical output of concentration versus distance produced on your printer MODEL This model is described in the EPA publication "Estimating Concentrations Downwind from an Instantaneous Puff Release" (PB82-261959), August 1982. The model is based upon the Gaussian Puff equation using the dispersion parameters presented in Meteorology and Atomic Energy. This progra has been converted for the IBM-PC with all of the features included in the original model. Verification test files are included. TRPUF TRPUF is based on the Puff EPA model. Several enhancements have been made to make the program easier to use in the PC environment. All input parameters are specified with simple interactive conmands. When TRPUF is started a screen of input items is presented. This screen contains the data used in the last run made. You simply enter the variable number you wish to modify. The computer will prompt you for the entry, verify the entry and then present the input screen again. The input screen is shown in Figure 1. Notice that all of the entries are relatively simple. There are no complicated variables to define. You also have complete control of the output format from units through fixed or scientific presentations. ------------------------ TRINITY CONSULTANTS, INC. When you select option zero from the input screen, TRPUF begins executing. The results are automatically printed on your printer as the model executes. Total execution times vary with different printers, but will be under two minutes for most printers. An example of the output is shown in Figure 2. This compact output displays both instantaneous and average concentrations at several downwind distances. Concentrations are included for all three stabilities as well as the concentrations. All input parameters are also shown. A The results of your TRPUF run are not only sent to the printer but are also placed in a disc file. Another program included in this package, PDIST, allows you to produce plots of concentration versus downwind distance* Again, you may design your output with simple interactive responses as shown in Figure 3. The output of PDIST is processed by the Golden Software package to produce high quality plots on your dot-matrix printer. Examples are included as Figures 4 and 5* GOLDEN SOFTWABK CttAfHTCS SYSTEM This complete graphics system is included in the TRPUF package. This system, developed by Golden Software of Golden, Colorado, is used to produce the concentrations versus distance plots* However, this package contains many additional capabilities including contour and three-dimensional plots, XT, graphs, bar charts, pie charts, line graphs and scatter charts. PRICE AND HARWIAttg REQUIREMENTS The complete TRPUF package is available for $995*00 for a single-use license. This package includes: o Both source and executable versions of the EPA Puff model and test data files o Both source and executable versions of TRPUF o Executable version of PDIST o Complete Golden Software Graphics System with all documentation o EPA guide for the EPA Puff model and Trinity Consultants guide for TRPUF o Telephone support services to help you get started. Hardware requirements are an IBM-PC, PC/XT or AT, or compatible; two floppy disc drives or one floppy and one hard drive; 256 kb of RAM; and a dot-matrix printer. A math coprocessor will decrease execution tiam, but is not required. TRINITY CONSULTANTS, INC VTtBTJOO1126436 PC-C A A company--wide license of the software. This license removes the restriction that only copies for backup purposes be made. The user is free to copy and distribute the software and manuals within a single company. The user is responsible for all reproduction. Questions about the software must be made by one person. The additional cost of this option is $500. You must have also purchased one copy of our single-use product TRINITY CONSULTANTS, INC 1 01126437 P PC-C TRPUF - HODS COPYRIGHT 1985 TRINITY CONSULTANTS, INC. 1) TITLE - EXAMPLE OF TRPUFS 2) RELEASE AMOUNT (POUNDS) * 3) MOLECULAR UEI6HT > 44.00 2.20500 4) AMBIENT TEMPERATURE (DEGREES F) * 08.00 5) AMBIENT PRESSURE (HD) * 1013.00 4) RECEPTOR HEIGHT ABOVE GRADE (FEET) * S. 7) AVERAGING TIME (SECONDS) 300. 5) EXIT VELOCITY (FEET PER SECOND) (USE 0 IF NOT A VERTICAL RELEASE) 5.000 P) STACK DIAMETER (FEET) * 1.500 10) DISTANCE FACTOR (USE 1 FOR THE STANDARD D0UMU1NB DISTANCES) * 1.0000 11) HIND SPEED (MPH) * 5.0 12) STACK HEIGHT (FEET) * 40.00 13) CONCENTRATION WITS < U6/H3 14) INITIAL PUFF CENTER CONCENTRATION (PPM) 5.00ET05 15) DISTANCE AT UHICH INITIAL PUFF SIZE IS KNOUN (FEET) * 0. 14) INITIAL HORIZONTAL STANDARD DEVIATION (FEET) .00 17) INITIAL VERTICAL STANDARD DEVIATION (FEET) * 15) OUTPUT FORMAT - SCIENTIFIC .00 ENTER VARIABLE NUMBER TO BE MODIFIED, 0 TO RUN, W TO STOP FIGURE 1VAB.0001126438 PC-C fRPUF - HODS COPYRIGHT 1985 TRINITY CONSULTANTS' INC. A PUFF MODEL DEVELOPED BY TRINITY CONSULTANTS' RICHARDSON' TEXAS EXAMPLE OF TRPUF3 214/234-8567 RELEASE AMOUNT (POUNDS) = 2.20500 RECEPTOR HEI6HT ABOVE GRADE (FEET) MOLECULAR WEI6HT = 64.00 EXIT VELOCITY (FEET PER SECOND) AMBIENT TEMPERATURE (DEG F) - 88.00 STACK DIAMETER (FEET) AMBIENT PRESSURE (MB) =1013.00 HIND SPEED (MPH) STACK HEIGHT (FEET) COMPUTED VIRTUAL DISTANCES (FT) HORIZONTAL VERTICAL UNSTABLE 3.3 3*3 NEUTRAL 16.4 16.4 STABLE 85.3 85.3 5. INITIAL CONCENTRATION (PPM) * 5.000 INITIAL HORIZONTAL SIGMA (FEET) 1.50 INITIAL VERTICAL SI6MA (FT) * 5.0 DOWNWIND DISTANCE (FT) * 60.00 5.00E+05 .00 .00 0. DOWNWIND PEAK INSTANTANEOUS CONCENTRATIONS DISTANCE (U6/M3) (FEET) UNSTABLE NEUTRAL STABLE MAXIMUM AVERAGE CONCENTRATIONS FOR 300. SECONDS SIGMAS (FEET) (UG/M3) TRAVEL UNSTABLE NEUTRAL UNSTABLE NEUTRAL STABLE MAXIMUM (MINUTES) HOB XR HOR VER 20 5.5409E-07 2 .2128E-09 6.7703E-09 5.5409E-07 1.7591E-09 4.542X-12 1.1093E 1.7591E-09 .045 3 7 2 3 1 40 2.0281E+01 7 .2767E-10 4.468X-09 2.0281E+01 11391E-01 2.2348E-12 8.5457E 60 1.9562E+03 3 .3662E-10 3.1362E-09 19562E+03 1.558X401 1.366X-12 6.843X 80 1.215X+04 1 .8649E-10 2.3043E-09 1.215X+04 1.2461E402 9.378X-13 5.6399E 100 2.B97X+04 1 1553E-10 1.7539E-09 2.8975E+04 3.6224E402 6.9102E-13 4.7519E 1.1391E-01 1.558X401 1.2461E402 3.6224E402 .091 .136 .182 .227 5 11 7 15 9 18 11 22 342 442 452 562 120 4.5077E+04 4.2469E-10 1.3728E-09 4.5077E+04 6.6321E402 2.9391E-12 140 5.6339E+04 1.9488E-07 1.0993E-09 5.6339E+04 9.5187E402 1.529X-09 160 6.2312EF04 1.7899E-05 8.9711E-10 6.2312E+04 1.187X403 1.5694E-07 180 6.4114E+04 5.3571E-04 7.4386E-10 6.4U4E+04 i35B6E403 5.1847E-06 200 6.3107E404 7.40B7E-03 6.2525E-10 63107E+04 1.4710E403 7.8394E-05 12 6.6321E402 *273 13 25 6 7 3 12 9.5187E402 .318 15 27 7 7 3 12 1.187X403 .364 17 30 8 8 3 12 1.3586E403 .409 19 33 93 12 1.471X403 .455 20 35 9 9 3 220 6.040X+04 5.9064E-02 5.3177E 10 6.040X+04 1.5350E403 6.779X-04 2.2469E 12 1.535X403 240 260 280 5.6808E+04 5.282X+04 4.8773E+04 3.1416E-01 1.2322E+00 3.824X+00 4.5695E 3.9622E 3.4633E 10 10 10 5.680X+04 5.282X+04 4.8773E+04 1.562IE403 1.562X403 1.5427E403 3.885X-03 1.6331E-02 5.4052E-02 2.0429E 1.868X 1.716X 12 12 12 1.5621E403 1.562X403 15427E403 300 4.484X+04 9.8854E+00 3.0491E 10 4484X+04 1.510X403 1.483X-01 1.584X 12 1.5103E403 320 4.1134E+04 2.209X+01 2.7017E 10 4.1134E+04 1.4692E403 3.5084E-01 1.469X' 12 1.4692E403 340 3.769X+04 4.3934E+01 2.4079E 10 3.7693E+04 1.4228E403 7.3567E-01 1.3666E 12 1422X+03 360 380 400 3.453X+04 3.1659E+04 2.9050E+04 7.941X+01 1.3271E+02 2.0776E+02 2,1575E* 10 1.9424E-10 1.7566E-10 3.453X+04 3.1659E+04 2.905X+04 1.3733E403 1.322X403 1.2717E403 1.3983E400 2.450X400 4.0143E400 1.275X* 12 1.1942E 12 1.1212E 12 1.373X403 1.3225E403 1.2717E403 420 2.668K+04 3.078X+02 1.5949E 10 2.6688E404 1.221X403 6.2112E400 1.0553E- 12 1.2215E403 440 460 480 24554E+04 2.262X+04 2.0882E+04 4.3556E+02 5.9227E+02 77844E+02 1.4536E 1.3294E 1.2198E 10 10 10 2.4554E404 2.2625E404 2.0882E404 1.172X403 1.1252E403 1.0797E403 9.156X400 1.2952E401 1.7680E401 9.9557E 9.4130E8.9179E* 13 13 13 1.1726E403 1.1252E403 1.0797E403 500 1.9305E+04 9.9350E+02 1.1225E 10 1.930X404 1.0361E403 2.3400E401 8.464X- 13 1,0361E+03 520 1.7877E+04 1.2360E+03 1.0359E 10 1.7877E404 9.9452E402 3.014X401 8.0487E- 13 9.9452E402 540 1.6583E+04 1.5038E4O3 9.5846E 11 1.658X404 9.5490E402 3.793X401 7.6657E- 13 95490E402 560 580 600 1.5408E+04 1.4339E+04 1.3366E404 1 7940E+03 2.103X403 2.4290E+03 8.8899E 8.2645E 7.6997E 11 11 11 1*540X404 1.4339E404 1.3366E404 9.1724E402 8.8147E402 8.475X402 4.6751E401 5.656X401 6.7328E401 7.3121E6.9849E' 6. XIX* 13 13 13 9.1724E402 8.8147E402 8.475X402 620 1.2478E+04 2766X403 7.188IE-11 1.2478E404 8.1534E402 7.8978E401 6.3992E- 13 8.1S34E402 640 660 680 1.1667E404 10924E404 1.0244E+04 3.1135E403 3.4656E403 3.8200E403 6.7234E-11 6.3002E-11 5.9138E-11 1.1667E404 1.0924E404 10244E404 7.8480E402 7.558X402 72838E402 9.1440E401 1.0463E402 1.1847E402 6.136X* 13 5.891X* 13 5.661X- 13 78480E402 7.558X402 7.2838E402 700 9.6184E+03 4.1736E403 5.5602E-11 9.6184E403 7.0232E402 1.3285E402 5.4467E* 13 7.0232E402 .500 .545 .591 .636 .682 .727 .773 *818 .864 .909 .955 1.000 1.045 1.091 1.136 1.182 1.227 1.273 1.318 1.364 1.409 1.455 1.500 1.545 1.591 22 X 24 40 26 43 28 45 30 47 31 50 33 52 35 54 37 X X 58 40 60 42 62 44 65 45 67 47 69 49 71 51 72 52 74 54 76 56 78 57 80 59 82 61 84 62 86 64 87 10 10 11 10 12 11 12 12 13 12 14 13 15 13 15 14 16 14 17 15 18 15 18 16 19 16 20 17 21 17 21 17 22 18 23 18 24 19 24 19 25 20 26 20 26 21 27 21 28 21 4 4 4 4 5 5 5 5 5 6 6 6 6 6 7 7 7 7 7 8 8 8 8 8 9 1 2 2 2 2 2 2 2 2 2 3 3 3 3 3 3 3 3 3 3 4 4 4 4 4 4 4 4 4 4 4 4 4 5 5 FIGURE 2 VAB.0001126439 Page 1 of 2 * PC-C A TRPUF - 0D5 COPYRIGHT 1985 TRINITY CONSULTANTS, INC. A PUFF NODa DEVELOPED BY TRINITY CONSULTANTS, RICHARDSON, TEXAS 214/234-8547 EXAMPLE OF TRPUF5 RELEASE AMOUNT (POUNDS) * 2.20500 RECEPTOR HEIGHT ABOVE GRADE (FEET) * 5. INITIAL CONCENTRATION (PPM) * MOLECULAR WEIGHT = 64.00 AMBIENT TEMPERATURE (DEG F) = 88.00 EXIT VELOCITY (FEET PER SECOND) * 5.000 INITIAL HORIZONTAL SIGMA (FEET) STACK DIAMETER (FEET) * 1.50 INITIAL VERTICAL SIGMA (FT) * AMBIENT PRESSURE (MB) *1013.00 WIND SPEED (MPH) * 5.0 DOWNWIND DISTANCE (FT) = STACK HEIGHT (FEET) = 60.00 COMPUTED VIRTUAL DISTANCES (FT) HORIZONTAL VERTICAL UNSTABLE 3.3 3.3 NEUTRAL 16.4 16.4 * STABLE 85.3 85.3 5.00E405 .00 .00 0. DOWNWIND PEAK INSTANTANEOUS CONCENTRATIONS DISTANCE (UG/H3) (FEET) UNSTABLE NEUTRAL STABLE MAXIMUM * AVERAGE CONCENTRATIONS FOR 300. SECONDS SIGMAS (FEET) (UG/M3) TRAVEL UNSTABLE NEUTRAL STABLE UNSTABLE NEUTRAL STABLE MAXIMUM (MINUTES) HOR VER HOR VER HOR VER 800 900 1000 1100 1200 7.1553E+03 5.8442E+03 4.1752E-11 71553E+03 5.9044E+02 2.0986E+02 4.5504E-13 5.9044E402 5.4742E+03 4.2882E+03 3.4273E+03 7.2158E+03 8.2037E+03 8.8252E+03 3.2330E-11 2.5660E-11 2.0786E-11 7.2158E+03 8.2037E+03 8.8252E+03 5.0321E+02 4.3417E+02 37B70E+02 2.8807EF02 3.6025E+02 4 *2249E+02 38755E-13 3.3524E-13 2.9373E-13 5.0321E402 4.3417E402 4.2249E402 2.7S67E+03 9.1378E+03 1.7128E-11 9.1378E+03 3.3350E+02 4.7338E+02 2.6012E-13 4.7338E402 1300 2.2997E+03 9.2101E+03 2.2435E-11 9.2101E+03 2.9620E+02 5.1310E402 3.6422E-13 5.1310E402 1400 1.9225E+03 9.1056E+03 3.2298E-10 9.1056E+03 2.6504E+02 5.4262*02 5.5789E-12 5.4262E402 1500 1600 1700 1.6255E+03 1.3882E+03 1.1942E+03 8.8774E+03 8.5673E+03 8.2069E+03 4.2657E-09 4.0331E-08 2.8638E-07 8.8774E+03 8.5673E403 8.2069E+03 2.3874E+02 2.1634E+02 1.970VE+02 5.6329E+02 5.7651E+02 5.8361E+02 7.8081E-11 7.7955E-10 5.8267E-09 5.6329E402 5.7651E402 5.8361E402 1.818 2.045 2.273 2.500 2.727 2.955 3.182 3.409 3.636 3.864 72 96 81 105 89 113 97 122 105 129 113 137 121 145 129 152 137 160 145 167 32 23 10 35 25 11 39 27 11 42 29 12 45 31 13 49 33 14 52 34 13 56 36 16 59 38 17 62 39 18 5 5 6 6 6 7 7 7 7 8 1800 1900 2000 2500 1.0390E+03 7.8191E403 1.6029E-04 7.8191E+03 1.8041E402 5.8578E+02 3.4233E-08 5.8578E402 9.0896E+02 7.4205E+03 7.3509E-06 7.4205E403 16587E402 5.8401E+02 1.6438E-07 5.840IE102 8.0039E+02 4.5860EF02 7.0225E403 52344E403 2.8491E-05 4.1562E-03 7.0225E403 5.2344E403 1.5310E402 10768E402 3.7917E402 5.2927E+02 6.6561E-07 1.1757E-04 5.7917E402 5.2927E402 3000 2.S996E+C2 39020E403 9.5734E-02 3.9020E403 8.0500E401 4.6614E+02 3.1695E-03 4.6614E402 4.091 4.318 4.545 5.682 6.818 3500 1.9643E402 2.9558E403 7.9806E-01 2.955SE403 6.2828E401 4.0661E402 3.0201E-02 4.0661402 7.955 4000 4500 5000 5500 1.4003E402 2.2832E+03 3.6077E+00 2.2832E403 5.0615E40! 3.5495E402 1.5335E-01 3.5495E102 1.0382E4-02 7.9402E+01 6.2281E+01 17977E+03 1.4406E403 1.1727E403 11004E401 2.5727E401 49876E401 1.7977E403 14406E403 1.1727E403 4.1762E401 3.5087E401 2.98V3L401 3.1133E402 2.7478E402 2.4412E402 51837E-01 1.3288E400 2.8004E400 3.1133El02 2.7478E102 2.4412E102 9.091 10.227 11.364 12.500 152 174 66 41 19 8 160 181 49 43 20 8 168 188 72 44 21 8 206 221 89 51 25 10 244 252 105 58 29 11 281 283 121 65 33 12 317 311 136 71 37 13 354 339 152 77 41 1* 390 366 167 83 45 14 425 393 163 89 49 15 6000 6500 7000 7500 8000 4.9885E401 4.0665E401 3.3651E401 2.8210E401 9.6808E402 8.0917E402 6.8386E402 5.8368E402 8.*380E+01 1.2893E402 1.8222E402 2.4232E402 9.6808E402 8.0917E402 6.8386E402 S.8368E402 2 5747E401 2.2371E401 1.9579E401 1.7242E401 2.1B27E402 1.9635E402 1.7762E402 1.6151E402 5.1133E400 8.3816E400 1.2643E401 1.7867E401 2.1827E402 1.9635E402 1.7762E402 1.6151E402 2.3918E401 5.0261E402 3.0710E402 5.0261E402 1.5266E401 1.4756E402 2.3965E401 1.4756E402 13.636 14.773 15.909 17.045 18.182 461 419 198 95 53 16 496 444 213 100 57 17 531 468 228 105 61 15 566 493 243 111 65 IE 600 516 258 116 68 1? 8500 9000 10000 10500 11000 2.0482E401 4.3625E402 3.743SE402 4.3625E402 1.3582E401 1.3541E402 3.0816E401 1.3541E402 1.7694E401 1.3510E401 1.1923E401 1.0583E401 3*8138E402 2.9706E402 2.6438E402 2.3647E402 4.4211E402 5.7276E402 6.3328E402 6.8952E402 4.421 IE402 5.7276E402 6.3328E402 6.8952E402 1.2137E401 9.8079E400 8.8642E400 8.0373E400 1.2475E402 1.0700E402 9.9554E401 9.2879E401 3.8274E401 5.4414E401 6.2811E401 7.1257E401 1.2475E402 1.0700E402 9.9554E101 92879E401 19.318 20.455 22.727 23.864 25.000 635 540 669 563 272 121 287 126 72 76 220` 737 608 316 135 83 22 771 630 331 140 87 23 805 651 345 145 91 23 11500 12000 12500 13000 13500 9.4439E400 2.1247E402 7.4202E402 7.4102E402 7.3110E400 8.6865E401 7.9645E401 8.6865E402 8.4680E400 7.6266E400 6.8971E400 1.9172E402 1.7368E402 1.5790E402 7.8752E402 8.2893E402 8.6532E402 7.8752E402 8.2893E402 8.6532E402 6.6695E400 6.1012E400 5.5960E400 8.1422E401 7.6473E401 7.1957E401 8.7887E401 9.5908E401 1.0365E402 8.7887E101 9.5908E401 1.0365E402 6.2607L400 1.4404E402 8.9682E402 8.9682E402 5.1454E400 6.7820E401 1.1107E402 1.1107E402 24.136 27.273 28.409 29.545 30*682 838 673 872 694 905 715 938 736 971 757 360 149 94 374 154 98 388 158 102 402 163 105 417 167 209 24 25 25 26 26 FIGURE 2 -------- 126440 I- PC-C LOPTRIBKT 1*85 TRINITY CONSULTANTS, INC READING DATA* PLOT 1YPE* (LIN*L1NEAR, L06*L0G-L0B)? L06 ta. MINIMUM DOWNWIND DISTANCE (FEET) (USE 0 FOR ALL DISTANCES)? 0 MAXIMUM DOWNWIND DISTANCE (FEET) (USE 0 FOR ALL DISTANCES)? 0 ENTER I FOR INSTANTANEOUS, A FOR AV6RABE CONCENTRATIONS I SELECT THE STABILITY CLASS - ENTER U - UNSTABLE N - NEUTRAL S - STABLE M - MAXIMUM OF THE THREE STABILITIES ENTER U, N, S, OR M? H r\ t FIGURE 3VAB.0001126441 EXAMPLE OF TRPUF5 ID 4Oo GO LU o + CD < (/) K> < + C O ro CM O 4* OU 00 o < or 2 LU O o8 o? X < O I g i DISTANCE PC-C A E+05 FIGURE 4 VAB.0001126442 EXAMPLE OF TRPUF5 PC-C DISTANCE (FT) *10' FIGURE 5 VAB.0001126443 PRACTICAL PLANNING FOR TOXIC GAS RELEASES July 31, 1985 Your evaluation of this course would help make future workshops more useful to others. Would you please fill out this evaluation and return it in the enclosed stamped envelope. Coverage of Subjeet Technical Depth Usefulness Appropriate .Appropriate Very Practical .Too Little .Too Simple .Average Too Much Too Advanced Limited Organization of Material Presentation Length of Course Well Planned Good Too Long .Average Average Too Short Poor Poor About Right How would you rate the course overall? __^Excellent Good Adequate + 4 If given again, would you recommend the course to your associates? ____Yes ____No PLEASE CONTINUE ON REVERSE SIDE TRINITY CONSULTANTS, INC. ------------------------ ^ : VAB.0001126444 4 PRACTICAL PLANNING FOR TOXIC GAS RELEASES Richard H. Schulze July 31, 1985 Trinity Consultants, Inc. 100 N. Central Expressway Suite 600 Richardson, Texas 75080 (214) 234-8567 * TRINITY CONSULTANTS, INC faxt* cJrfe^ -<iv^AL if <*<**- 4)67^ /^>)CM8^ ^> S^LfJlcj d? A'l tffao-tiAo E~f> S-\u/<4^ T^cflv Efi^ -*0'C&+*. . OHtij~&* 6ac$1a. . * C<4>fiJ* S) fk)~32o//fW6 % n J VAB.0001126446 PRACTICAL PLANNING FOR TOXIC GAS RELEASES REGISTRATION LIST Houston, TX - July 31, 1985 Mr. Allen Jurisich Senior Program Advisor, Environmental Service Cigna Loss Control 139 West Livingston Place Metairie, LA 70005 (504) 831-1617 Mr. John Brau Employee Relations Manager Sohio Chemical Company Box 659 Port Lavaca, TX 77979 (512)552-8218 Mr. Joe Ledvina Director of Environmental Activities Vista Chemical Company P.0. Box 19029 Houston, TX 77224 (713)531-3451 Ms. Ailleen Teng Senior Environmental Health Specialist Cigna Los8 Control Service 12815 Leader Houston, TX 77072 (713)933-1826 Mr. Ron Pertuit Texas Eastern Company P.0. Box 7444 Longviev, TX 75607 (214) 236-5000 ext. 2760 Mr Joe Woo lbert Texas Eastern Company P.0. Box 7444 Longviev, TX 75607 (214) 236-5000 ext. 2760 TRINITY CONSULTANTS, INC PREFACE This manual is designed for use with a one-day short course entitled "Practical Planning For Toxic Gas Releases". I decided that it was best to prepare a manual instead of a set of notes. This course was offered for the first time in April, 1985. This manual is prepared as a result of comments on the first course and research I conducted since then. I would welcome any ideas or suggestions for making this manual a more effective teaching tool. RICHARD H. SCHULZE Richardson, Texas July 24, 1985 TRINITY CONSULTANTS, INC TABLE OF CONTENTS I Introduction A. Regulations Affecting Toxic Gas Accidents B. Affected Industries II. Atmospheric Turbulence A. Description of Turbulence B. Categories of Atmospheric Turbulence III. Flume Dispersion A. Gaussian Models B. Accuracy of Models C. Pasquil1-Gifford Coefficients D. Continuous Release Equations E. Description of Puff Release F. Puff Model Dispersion Coefficients G. Average Concentrations from Puff Releases H. Puff Equations I. When to Use Puff or Continuous Release Models IV. Initial Cloud Size and Building Wake Effects A. Accounting for Initial Cloud Size B. Virtual Distance Method C Conversion of Concentration Units D. Obstructions V. Effective Stack Heights A. Briggs1 Buoyancy Formula 1. Buoyancy Flux 2. Wind Speed 3. Restoring Acceleration 4. Size of Plants B Plum Rise of Flares 1. Calculating F from Heat Release 2. Losses Due to Radiation 3. Effect of Addition of Steam C Briggs* Momentum Formulas VI. Toxicological Considerations A. Chronic and Acute Toxicity B. Air Contaminant Limits in the Work Place C. Air Contaminant Limits in the Ambient Air D. Time Averaged Concentrations E. Method Used by EPA for Chronic Toxicity Studies TRINITY CONSULTANTS, INC 1 a 6 '6 13 24 24 25 26 26 37 38 41 45 45 48 48 50 51 52 58 60 63 64 65 66 66 68 70 71 77 80 80 81 83 84 87 VII* Large Spills and Heavy Gases A. Common Dilute Clouds B. Description o Spills 1. Liquid Spills 2. Liquid Gas Spills a. Small Hole in Vapor Space b. Large Hole in Vapor Space c. Hole in Liquid Space d. Dense Gas Cloud e. Description of Releases f. Shape and Characteristics of Dense Gas Clouds g. Modeling Dense Gas Clouds 3* Gas Spills C. Bursts with Continuing Emissions D. Lover Flammable Limits VIII Location of Spills and Data Required A. Transportation B. Accidents at Plant Sites I IX. Techniques for Reducing Risk X. Computer Models A. SPILLS B. SAFER I C. CHARM i i4 D. CARE ii| E. HASTE F. EPCHEMS II i G. MESOCHEM, JR. H. Other Systems I. EPA Puff J. TRPUF K. PTPLU L. PAL M. ISCST N. VALLEY O. TEM8 XI. Evaluation of Risks A. Development of Accident Scenarios B. Causes of Failures C. Hazard and Operability (HAZOP) Studies D. Risk Analysis 1. Analyzing Risk 2. Computer Model 3. Value of Risk Analysis I TRINITY CONSULTANTS, INC A 90 90 91 91 93 93 94 95 95 97 99 101 102 102 103 105 105 110 121 121 124 127 128 129 130 130 131 131 132 137 137 138 142 144 148 148 150 151 152 152 154 155 1126450 FIGURES A 1. Average Wind Speed Anniston Airport (Surface) and Plant (500* Elevation) 2. Description of Atmospheric Stability Categories 3. Combinations of Wind Speed and Stability Analyzed by PTMAX 4* Frequency of Occurance of Wind Speed and Stability Combinations 14 15 17 19 5. Coordinate System Shoving Gaussian Distribution in the Horizontal and Vertical 6. Vertical Dispersion Coefficient as a Function of Downwind Distanc from the Source 7. Constants Used to Calculate o* in EPA Developed Programs 8. Horizontal Dispersion Coefficient as a Function of Downwind Distance from the Source 9* Constants Used to Calculate Oy in EPA Developed Subroutine DBTS1G 32,33 10. Horizontal Dispersion Coefficients - Pasquil1-Gifford and those 39 for Quasi-Instantaneous Releases 11. Vertical Dispersion Coefficients - Pasquil1-Gifford and those 40 for Quasi-Instantaneous Releases 12. Dispersion of a Puff from a Pipeline Break 42,43,44 13 Growth of Wake 14, Ratio of Calculated to Observed Values of Ah 15, Schematic Mollier Chart 16, Safety Factors Used to Derive Acceptable Ambient Concentrations from Occupational Limits 54 61 73 85,86 17. Guide 20 - Emergency Response Guide Book (1984) 18. Table of Isolation & Evacuation Distances 19. Station for Collecting Meteorological Data 20. Major Differences Between TRPUF and EPA Puff Models 107 108,109 112 134 21. Tabular Output of TRPUF 22. Graphical Output of TRPUF 23. Terrain Adjustments for Selected Gaussian Models 135,136 137 145 TRINITY CONSULTANTS, INC r VAMT00I 126451 I. INTRODUCTION A * v The purpose of this manual is to help the engineer, safety specialist or other technically trained person prepare for and evaluate the dispersion of a potentially toxic gas. Some compounds will enter the atmosphere as a gas while others will be the result of evaporation from a liquid pool. Interest in this subject, at least judged by inquiries to our firm, has increased steadily since 1980. It was the tragic events in Bhopal, India, in December, 1984, that has galvanized corporations -i and regulatory agencies to re-examine their contingency plans. A. Regulations affecting Toxic Gas Accidents For the most part, toxic gas releases are not subject to environmental regulations. In contrast, oil spill planning is. In 40CFR112, detailed requirements are set forth for the preparation of Spill Prevention Control and Countermeasure Plans (SPCC Plans). The preparation of plans is required if an organization stores more than 42,000 gallons in an underground tank or 1,320 gallons in above ground containers. Surprisingly, no such plan is required for the discharge of hazardous substances in waste waters but the reporting of such a discharge is required by 40CFR116 and 117. In general, the response to any toxic gas accident is handled by l TRINITY CONSULTANTS, INC. 1126452 T mm local public safety personnel such as the State Police, a city fire department, the Sheriff or special disaster response teams* In nearly all cases, the scope and detail of any contingency plan is a decision made by the organization which manufactures, transports or stores hazardous materials. In some instances local emergency response organizations are involved with the planning performed by the manufacturer, storer or transporter of hazardous materials* Outside the United States, the British have led the world in addressing the problem of toxic and hazardous substances* S*I* 1982 No. 1357 is entitled "The Notification of Installations Handling Hazardous Substances Regulation". S*I. 1984 No. 1902 is entitled "The Control of Industrial Major Accident Hazards Regulations". The first of these regulations enabled the Health Safety Executive to identify installations and define priorities for inspection programs. The second requires, smong other things, the preparation of a hazards analysis, an emergency plan, and an off~site emergency plan. It also requires that members of the public living in the vicinity of an industrial activity be informed about the activity and associated hazards. The Appendix contains a flow chart of the regulations taken from the Health Safety Executive Guide for the 1984 regulations. These regulations implement Directive 82/501/EEC of the European 2 ---------- TRINITY CONSULTANTS, INC. In February, 1985, the World Bank issued a draft guideline entitled TfWorld Bank and IFC Guidelines for Identify Analy zing and Controlling Major Hazard Installations in Developing Countries". It is based on the two British regulations and is currently used to evaluate proposed countries that are seeking funding frc the World Bank. This draft is included in the Appendix. B. Affected Industries There are certain industries and organizations that have risks associated with toxic gas releases. Broadly speaking, releases can occur in transportation accidents or at plant or warehouse sites. The chemical industry manufactures materials such as chlorine and ammonia. In addition, the plant chemical ind uses i number of toxic gases as intermediates in the final products. These include phosgene, phosphine of the Bhopal disaster, methyl isocyanate. * Chlorine is the most ubiquitous of the hazardous gases. It is widely used throughout the country for drinking water treatment and in the sterilization of swimming pools. Ammonia is also widely used, primarily as a fertilizer. Ethylene oxide is used in the sterilization of equipment, ------------ TRINITY CONSULTANTS, INC. --------------- VArOOt5ll26454 supplies and disposable items used in the medical field. Although large volume sterilizers such as the manufacturers of plastic disposables have facilities equipped vith scrubbers, many smaller users, such as hospitals, do not. About 20 percent of the natural gas produced in the United h States contains some hydrogen sulfide which must be removed before the gas is delivered to common-carrier pipelines. There is risk both in drilling for gas and in processing the gas. Hydrogen sulfide is also of concern in refineries where up to several tons of the compound can be contained in pipelines or process vessels. The liquid extraction of elements such as sulfur or bromine often involves processing hydrogen sulfide. j The semi-conductor industry uses some unusually toxic gases such as arsine, hydrogen selenide and phosphine in the manufacture of wafers. As the use of metal--organic vapor phase epitaxy reactors come into wider use, increased quantities of these hazardous gases will be used. Human error is another major cause of toxic gas releases Water in place of nitrogen was introduced to the storage tank of methyl isocyanate in Bhopal. Operators have pumped a caust ic solution into a sulfuric acid tank. Maintenance personnel have used inappropriate chemicals to clean a contaminated tank. Material in an epoxy resin blending tank got too warm and started a reaction which caused a cloud of gas to drift over a nearby school. 4 TRINITY CONSULTANTS, INC AB: 1126455 Transportation spills are difficult to assess. The most elaborate system is operated for the Department of Defense by Lawrence Livermore Laboratory. If a nuclear weapon accident occurs anywhere in North America as a result of a plane crash, a missile silo accident or other cause, the direction and concentrations in the released material can be forecasted. More commonly, however, a trucking or railroad accident occurs and local public safety officials do the best they can to reduce the risk to those nearby. The most difficult task, however, is to determine the quantity of gas released. When a tank car is laying in a ditch it is difficult to determine whether the tank has a small puncture or a large gash. The major uncertainty in most situations is the value of the "source term", that is the quantity that is or was actually introduced into the atmosphere. Next, in order of uncertainty, are the meteorological parameters. Finally, there is the inherent uncertainty regarding the accuracy of the model. In summary, there is usually a great deal of uncertainty, and thus, most analyses of actual or potential accidents tends to stress the "worst case". i 5 TRINITY CONSULTANTS, INC. - II. ATMOSPHERIC TURBULENCE A. Description of Turbulence Atmospheric turbulence is caused both by the wind and by surface heating and cooling (thermal) effects. The meteorological terms are mechanical and convective turbulence.1 An atmosphere that is well mixed because of strong winds - vigorous mechanical mixing in meteorological terms - under overcast skies is termed "neutral." Under these conditions, there are no surface heat ing or cooling effects and the temperature decreases with altitude at the "ADIABATIC LAPSE RATE". Lapse rate is the change in tem perature with elevation. This is illustrated as follows: HEIGHT ABOVE GROUND z or h Pasquill Stability Class D ADIABATIC LAPSE RATE IS -5.4F/1000 FT OR 'v-0.01 "C/METER DUE TO MECHANICAL TURBULENCE ONLY. This condition is typical of over cast days and nights with strong winds. TEMPERATURE This is an idealized illustration. The actual lapse rate shows a variable change in slope, particularly with lighter winds. In TRINITY CONSULTANTS P.O. BOX 31481 DALLAS, TEXAS 75231 * VAB.0001126457 the Pasquill system of categorizing stability, this condition is called D. Sometimes meteorologists refer to the potential lapse rate. This term is equal to the actual temperature lapse rate less the adiabatic lapse rate. For example if the actual lapse rate is 0.01C/m, the potential lapse rate is 0.02C/m (O.Ol-(-.Ol)). If the winds are moderately strong, in excess of 10 m/sec, the atmosphere is well mixed from the surface to the top of the boundary layer. The boundary layer is usually defined by an upper air inversion, vhere the slope of lapse rate becomes positive or nearly so. When the vinds are lighter under overcast skies, the atmosphere can be considered to consist -t I- of a number of mixing zones. Surface friction will create a turbulent zone between 10 and 100 meters thick. Above this will be zones that exhibit relatively laminar flow. The transition between the zones is quite gradual. The primary source of surface heat on the earth is the sun, or more exactly, solar radiation. As the sun rises in the morning or as an overcast sky becomes partly cloudy, a larger amount of solar radiation reaches This causes the air near the surface to warm and cells' of this warm steam is formed on the bottom surface of a pot of boiling water. The amount determined largely by the cloud cover and 7/85 7 TRINITY CONSULTANTS, INC the elevation of the sun (solar insolation). The more direct the sunlight, the more heating of the surface and the greater the thermally induced, convective, turbulence. As the cells of warm air leave the surface, they are replaced by downward moving cells of colder air. This condition is typical of sunny days when the sun has warmed the earth. It is called "unstable," ''superadiabatic," "overturning," or "advectlng" because of thermally induced turbulence. The unstable conditions have been subdivided into three categories by Pasquill: A, B, or C. Turner refined Pasquill*s definitions somewhat to facilitate the use of computers to determine stability from routine surface observations. Category A applies when the sun is 60 or more above the horizon and the sky is cloudless or nearly so. Category B applies when the sun has less elevation or the sky is cloudier. Category C is only slightly unstable. Under 8 TRINITY CONSULTANTS P.O. BOX 31481 DALLAS, TEXAS 75231 VAB.0001126459 these conditions, the lapse rate is called "superadiabatic," 11 overturning," "unstable," or "advecting". number help in understanding convective turbulence better. Briggs enumerates these in a 1975 review. During the day, convective turbulence strongly mixes the lower atmosphere, but this mixing abruptly ilxing layer. Nearly all of the time there is a stable air (a lapse rate with a positive slope) layer aloft that acts as a lid on mixing. In rural areas on clear mornings the mixing zone starts as a shallow layer near the ground at sunrise and continues to increase during the day as long as * the radiation input from the sun exceeds the earth's outward radiation* The lower boundary of the upper air stable layer increases in height as more of this stable air becomes Involved in the convective turbulent layer. The temperature gradient is superadiabatic only in the lowest tenth or so of the mixing depth and just slightly less than adiabatic above this. The mixing layer consists of upward ther mals carrying heated air from the surface and of compensating downdrafts. The turbulence is much greater inside the thermals than in the subsiding downdrafts. Extremely unstable conditions j ii 9 TRINITY CONSULTANTS P.O. BOX 31481 DALLAS, TEXAS 75231 -- VAB.0001126460 A can only exist during periods of light winds. Moderately unstable conditions can exist with winds up to moderate speeds. As night comes and solar radiation ceases, the earth cools as It radiates heat. The earth, like the sun, radiates heat In propor tion to the fourth power of the absolute temperature. In the absence of wind, the cooling air near the surface shrinks In volume and tends to settle. This results in cool air tending to "drain" downhill. For example, in the fall, frost will most often first occur in the valleys rather than on the tops of the hills. This condition is typical of relatively cloudless nights with light winds. The elevation at which the actual lapse rate reverses is the depth of the "inversion layer". This condition is called ''stable". Pasquill divided the stable conditions into two categories. 10 TRINITY CONSULTANTS p.o. box 31481 Dallas , texas 75231 VAB.0001126461 and and Stability F applies to calm clear nights in rural The United States Environmental Protection Agency uses a potential lapse rate of 0.02C/m for E and 0*035C/m for F stability or actual lapse rates of 0.01C/m and 0*025C/m respectively for E and F* During the Arctic winter, rather severe inversions can occur* During extended periods of cloudless still days with virtually no sun, lapse rates of *036 to *055 degrees per meter are not uncommon in places such as Fairbanks, Alaska* Strong inversions can also occur at the surface as warm winds blow across cold bodies of water* This is ft typical of spring conditions on the Great Lakes* It can also occur as cold winds are drawn in across land such as in the Los Angeles basin* Stabilities stronger than E or F are sometimes referred to as G and H. After sunrise on clear mornings, the sun starts to heat the surface. The layer of thermally induced turbulence starts at the surface and gradually increases in depth as it erodes the stable layer from beneath* The inversion layer generally disappears within 5 to 7 hours after sunrise* t 7/85 11 TRINITY CONSULTANTS. INC 9 1126462 A NEUTRAL STA8LE \ UNSTABLE This condition is typical of the period after sunrise when the sun starts to warm the surface and the night-time inversion starts to disappear Mixing takes place only within layers in the atmosphere, not between the layers. Thus in the morning situation just described, the layer closest to the ground will be very well mixed due to the vertical motions typical of superadiabatic conditions. The start of the stable layer forms a lid. If pollutants were emitted into the stable layer during the night, they would remain in this layer until the unstable layer erodes the stable layer and reaches a depth equal to the centerline of the plume. At this point, the pollutants will be mixed rapidly in the un stable layer. Meteorologists call this condition "Inversion Breakup Fumigation" 12 TRINITY CONSULTANTS P.O. BOX 31461 DALLAS, TEXAS 7S231 T VAB.0001126463 Under typical daytime conditions, after disappearance of the noc turnal inversion layer, the surface boundary layer continues to have a reasonably well-defined upper limit that is usually between 500 and 2000 meters deep. At night the surface layer is stable in nature and is not nearly as deep as the daytime layer because of the absence of ground thermals. The diurnal changes in the atmosphere are illustrated in Figure 1. It shows average wind speeds by hour for the 27 days of June at an Alabama location at a 10-meter elevation and at a nearby 150- meter elevation. It is apparent that there is a strong inversion at night. The surface wind speed is a small fraction of the wind aloft. By about 0900 the surface has become warmed so that good r vertical mixing is occurring and the winds at the surface are equal to those aloft. This condition continues past mid-day when the cumulus clouds start to increase. By evening the winds subside. At night only the aloft winds increase, suggesting a surface-based inversion. Categories of Atmospheric Turbulence Figure 2 is the description of Atmospheric Stability Categories taken from Turner's "Workbook of Atmospheric Dispersion Estimates". This table is similar to that on page 368 in F. Pasquill, "Atmo- ----------------- 13 TRINITY CONSULTANTS P.O. BOX 31411 DALLAS. TEXAS 73231 VAB.0001126464  4 W p*4 W J *P > pto 4 < v* * ^ * * * + * * t * * +^i* 4 1 J * ** * * * 1 ^ * * 4* 4 ^ P -- 4Up ** w * ^ *****!+ * pa#* | * * a > ^ > *f p# i . 4 a + i m w- * a * ^ *1 * a* r a * - m m # * * - * # -*** * * * ** f >* f * ^ ` * * ^ + #w * a j ^ ^ .p ^ 1 a a * - -- -- ^ -- m* . 1 *a* * ** ** * 1 *1 * ---- V m T-m^m 4 4W 4Ua^ a * a ^ * * * -X * 4 * A t t | * 4 * ^ * tala* * * M * **** * * * * apa * HB|V _ __ _ ^ . , 4v w 1. 4 * * * a 4 , 4 < m n ^ t - 4 i > a t a a ' * v ## ^ p ***# i * ^ .4 1 *4 # *<j***i,-*`' *f>**#> '4 - -- a ** * * ^ # 4 a p^4 t # F ^ m B *4 -a I *a I * l--P*^*--p**y *" *--*--^ --*p--1*1----^WW-- - I --* * a ' i * | ' * + < * * # t *1 * * m ****** aa *-***- **., a# a M ^-__*** Ah * " '" ' * h f * * I 4 . f^a -i>- hit L a I^ -# *I * | * * * *^ * ' ` ' 'J & * -* #4 * * * > # *4*1 < * "-* * * *1 - p a a > . . <*** ^, v * , *-a 4 P < ^ #> a^ h* a ^ -* p | *h 4 # A 1 p a * * * * T 11 - * ^a f * * - h #**< ' a * h ________ pp m a a>^a 4* if*i w < a pa. -- * * a* 4W a 4 w . f * 1 # . *- a * *-- * *h* * a4 - a ^ a 1 ** 1 1 --r t* a a * m* * # | f - a * . f * * * t a P !*** 1 * * -* 1* r ` 4 ^ ft 1 a * m # ' t 11 * * 1 ' --.............................. ># * aMata * * 11 1 1 * B b . . t + ,*. aw- ** a 4 ww 1 a. ^4 ^ , 4 P P j t a a -- 9 1 *** * a w ,a + r4 * * 1t a* "" - '1 *a " ^ * p- m j- * 9. a p M . ha , B 4 a^M* - * - r , , . t - a a* t ** W* * ^P a a * * * I 1 * * *- - ' B a * * m b W a ^ ft *- - - a B * M * 4*^ a - < * # ^P aa - 1 4 a 4 a a M * a * - I *1 *g 4 ** * *- # - a - a a 'T * -a 1,4 f * * ** * * - ' I *'* ** 1` * a 4 1 * a a a 4 < * a a a^ a * a ^a - w m mm r t 4 a - * ft**ft*M-Bv w im p *<^aa a * m a a ava a a pmi ^ * a m^pm a ** a * a w * . .a , ^wb<-a *. 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' _ _t ___ " * * * _^^ FIGURE i AVERAGE WIND SPEED AT M-- a a * * ** J - .' *1 -"**-- ---frt ftlft f ^^ *1 -- B--f ap#4MBPM B4>B4HtMPfMliBt BWHMbPtsaiB b papataa^ * ' u " + a abb* ** * AW aa- MB 4h* 9A , ** ^ 1 -' 4B--a> r '- F . - ^ * ' I -_*- ... 4, , . - T * A - - - * F Fi i * 1 ++ .4.4 B4 f1 w 4Mft --------------- -- * W* _ __ -- I " ^ .ft * m *" ^v * ft _____ aa' ____ , -- -.-- m * * -^a m *-^a -a- .4 J __B ,A * a-- *p i a - -J r m m m* - -- n ________________ T ^w 4-^ia^-d __: ---.*. .-F*. * 4 ** a - - - 4* ^^ * "" *4*-.- --44-A M 1 B w a A* - a*4 A4B' * -a** h * 4 . . f u ____________ H n- - nMl^T! ,^:,, T*M"" T '. a ,* 1 " f i * _1 4 _ a- 11 ~ ^ iiJ _ ^ma-p* a** *^ ' * . * 4 ,, m* , ^ ^F , w-u. ^ . ^ T^ ^m ~ ** ------,, * + \ ,. * _ . _. * * ' ft. ft '" ^ "^ ! * * A Ba ___________ _ * *aaa * a - --- ^ I^Lm - -- 44 AA - *4 a a* a a -- * 1 a.* . "JiilLMT'Tlir^~^^ w* a . * . *.. * , *- * aM, w ^a p *,-> h a. F - . 4 .. k a^wa.i Q _.... ^.JU"_____ J1,... '."' 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Y*"" T~~7 ~~' ~--.1,..,a.7^" ^ ................... fa ^ *TM * * ^4- a w Ba a * * * * * Vt4+ a ** * * r,n ** * W ^* a 4 * *b** -- " - ^ b a a-a* # *^ a B a PB* # ^ *** 1 * # - - 4 * " *-- * + w-h *-a 1 '^ p *Bw 4 4 1**^ * *p * 4 - *^ | aa a a ^F * --^a^a^^^ai^a B^a a p a 4 a *m " ** * a * * 4^aa a# a a- a *-^m m w a a a a* 4-- a 4 ^ aa ^ ^ a* a a bm * * ^ * ** ^ - af - - -mm |a ' a# 1# 1441 m ^J ^ '____ ~ a a * a- -A # a f 4 j W A -^a H ^p .* a +-*a-Ha ` ** B - *' +^ ^ ` * "fc *^fcaiBB* T ** 4 ...................................... - *f aa**P 4 4*4 B I ._____ _. _ . ____ _ _________ I j__ * *- a ** - 1 BP* ^BaPB4*4PB^* * a- pw* a*a - - A4 w Ar a ^a - B*>^a ______ I ^ | *< 44a*A * P - 4 *B * W hi. r, 1 a wa**# - -* . *i *f * -A 4r AB *4a - < - - 4 | A 1 - h * i %L- ft ^ ^ # ft m m ft - ..a * * a- . a-a- .*...,. , .. , . _ ___ _. ** " a a. _. _ - ___ . _ w a m *- aBAB-a*- -*4, A^W a AM i v . + _ ^-- \ * H^ *ai ** ma b a 4 < aM ^^ *a b ft * * a a A-J V aa + m bb m Baa* ft B ft I ft * * "* ^ ^ * * ** * *"*'*' * 1 TM * ** ` ~p 4 bb a * b a. *- * - -- * b * i # * ** * a . ,^B | a-. | __ ................................... ---* - 4-4 a a-* * -- * B* ? * * * ^-F A M ^A-A .. . -, . .. m ... - 7. .TrT*t*^"" i rrr-1 "T'T* r*! "**" "\ j ."" ... * A, ^+ B .* A - .* M ^ -H - ^ ^^ * -- - * ** *~ * * * a 4 *ap#B Ba w a - * * - wba -& a. w a m a- a t ^^ m .^F pa* _. ^ __ . ___ ^L a^ * m- - * a -4V- * T " ' -* * #awa*- - a**A . a^ w a - w ft a- 4 *< * 4 w | a*- *4 - * a a - * * a _ m * * . a *- a a . | . . - a - a a-- - * a aa a 4 fe m ^ ^ *-w^^aa b a* * 4 a m a ^ * a a w *-- * a - * *- w** ^ ah * w aw* bb 4 * bp* a a a a * pa a * #i + ^ 4# # * - a * .- -- * AAA ** 4 4 m IA | B # *mmm ^ *'** wa a- B * * * > - *<* - * ^ ^^ * **#*+*.^ 4 fb p 4 ** * f - * * - ^ ^ t - .v p a-* , , * 4 ft ft ft ^F ft ' ** -. t -a -a -* * *a*aBA'--- -a a* ^ + # i* - ^ >* 4* - t 4a * 4 B^P -F 4 -a P B " a- v A* * 4AA *. 4 *a 4 a ' at a * B p p* * " *# *W - * * .4 - * * I t mm |i 4 ri* -4. -,> . | a p ,4 / ft ft .f F * .+ 4, # * 4 , P , 4 4 4 B > #a 4 * a -a * wp*i .*4 >f.^.. p. * a r ft (* * A . a a* *44 * ' A 4 +a *4 P4 TP t- *4 F 4 ft __ | ft a- ** * Px* 4 A -c A * f a a * - * i P * 1 4*- 4A4 4 , r f*, , , |, I 4 + 4* - *T ft ^M** c 4 < p p t ** * B* 41- * *! thBh ^ .v t'- < ft ._ 4* 4 i *4 , p.. .f . **. _I ._ ... **^ * * * B . ^^4 * 4 "^*1 ' * ^wa **-'- --a. i* k4 p 4 4 * r r A'-'-t+WW ^A * . '1 ^ ft 1 ft| ft l 1 1 a^w # a i M 4 - - * *t4 P t ^ AA h 4 . a^ -*B '* * ' ap ** .A *p . * * * * * I* # ' 4 - P B 4 a 44 4 ft H |a * * A - I-* -pip ** A * ____________ . m * 4 "^ 4a^-* a tt * i B * ** *^ * ^ " * *^ j1^ # | ** ft ^ hpl.A-F *" 1* wa aa aw- ' * * * * B * B *A *bb * ' ab I * . - A w*a * -*><- -i t * -| ** 11 * ^T l I ft * * ' '* *I ** f4 1 * a -BB # t 4 4 4 4a# - > -a. * ** M .B ..4 ___________________________________________ .. ____________________________________________________________________________________________________________________________________________________________________________________________ ...^ X . ** * ' ' B* -a. -- a *11 F , at*. * 4 t , ^i . , 4-** A. A- mm. - . A ^ A . aw f4 B^a* __ _ A * F * * * * * ** " ' *- 1 *-B M* *B * 1 * A 4- Pt , I4 . #.*Ah*4A* *' 4-* - * * 4 P Pf - F * * * * A A a * P __________r______________ iP j 4 - * *, #.B * ** ' F-4 A 4 *4 f * V A 4 - 7# # 4 - a * - *A *-*-' mft - 1 * II V. * ft | , 'ft"' a^A^^^V^ft F4 h ^ + .* B T . * ' * * *"A f4 T ,*A"4 P* * , * ' * A4A.A4-. 4 T* * ` 14 *4 44 * -. 4_ -V..A * h I .*_ +W a -. .................................................................................. A i 4 . I|. h F ^ .A F .P fl ' F.| A * 4 f a 4 y 4 t 4 MB P ' *"*" A-B B- A44A .| .4.. -AA* 4 ft < P * ^ * F 4 .4 * F * F J * *' - * F*4 *F .i A -4. ft + ,f . wBP *- - - 4 4m1 A* p *. I. 4 ---- -. *A j ^ft mm *' + T * *** T * AAA*" '4 ' I> * * P* * l-F * * a**wi-A A. * - a *4 . r ft ft M * ^, 4 -* 4 - t f 4 -A * A 4 A^ p * ' ' * i a. > a* - j -F P * * | t . * 4. f 4 - > - 4h > ^ -- P ft ft ft ft f o 41 o> <o __ m f- ie J P * 4 *a . m , +. o tr fmt * l I 4 4- *p * tO BB V3B.IHHii I2B4g5 CSXX) G33dS QNIM 5 FIGURE 2 DESCRIPTION OF ATMOSPHERIC STABILITY CATEGORIES I * I I # ! ! Surface Wind Speed at 10 m. Altitude 2.24 MPH * 1.95 Knots Day Incoming Solar Radiation Night Thinly Overcast 3.6 K?H *1.0 m/sec or ** <3/8 4 4*\ Strong Moderate Slight >4/8 Low Cloud Cloud <4.5 <3.9 <2 A A-B B 4.5-6.7 3.9-5.8 2-3 A-B B C EF 6.7-11.2 5.8-9.7 3-5 B B-C C DE 11.2-13.4 9.7-11.7 5-6 C C-D D DD >13.4 * >11.7 >6 The neutral category, D should be assumed for overcast conditions during day or night Night refers to a period from 1 hour before sunset to 1 hour after sunrise. For pur poses of the computer program Stability Category Al, B-2, etc. "Strong" incoming solar radiation corresponds to a solar altitude greater than 60 with clear skies in midsummer; "slight" insolation corresponds to similar conditions in midwinter or to a solar altitude from 15 to 35 with clear skies in midsummer. Cloudiness will decrease incoming solar radiation and should be considered along with solar altitude in determining solar radiation. Incoming radiation that would be strong with clear skies can be expected to be reduced to moderate with broken (5/8 to 7/8 cloud cover) middle clouds and to slight with broken low clouds. Caution should be used when forecasting to result in ambient concentrations with wind velocities of less than 2 meters per second (4.5 MPH or 3.9 knots). At low velocities the winds tend to meander widely. In addition, surface wind speeds at low velocities are rarely indicative of aloft velocities or of upper air stability Stability categories are reliable in open, rural areas. In urban and heavily wooded areas, the surface roughness and heat islands have an effect on the category, par ticularly on still nights. On calm clear nights stability E or F night occurs in rural areas where D is likely to occur over urban areas. *D. Bruce Turner, Workbook of Atmospheric Dispersion Estimates. U.S. Department of Health, Education, and Welfare, Revised 1970. * 15 TRINITY CONSULTANTS P.O. BOX 3148! DALLAS, TEXAS 7S231 w m A spheric Diffusion" (second edition). Turner defined stabilities in terms of solar insolation angles and cloud cover Instead of such terms as "sunny midday in summer in England" used by Pasquill. Turner also omitted a notation Pasquill used in his table which reads "for A-B take average of values for A and B etc." The Appendix contains the description of a computer algorithm that determines stability category from routine surface meteorological observations that is used in the "STAR" program. Figure 3 illustrates the Combinations of Wind Speed and Stability anlayzed by PTMAX, a computer program by Turner that analyzes a single stack. This matrix of stabilities and wind speed in PTMAX contains some inconsistancles, with Figure 2. According to Figure 2, stability A can't exist with winds in excess of 2 or 2.5 meters per second. Low wind speeds can exist for both C- and F-stabilities. PTMAX also analyzes wind speeds of 4 and 5 meters per second for F-stability that, according to Pasquill's definition, cannot occur. It is also questionable that any sort of modeling will be very accurate with winds of 1 meter per second or less. ' The National Climatic Center produces a "STAR" listing of the frequency of stability, wind speed, and wind direction based on historical meteorological data. The degree of atmospheric -tur-- 16 TRINITY CONSULTANTS P.O. BOX 31481 DALLAS, TEXAS 75231 VAB.0001126467 FIGURE 3 COMBINATIONS OF WINO SPEED AND STABILITY ANALYZED BY PTMAX Shaded area indicates 49 combinations of wind speed and stability analyzed by PTMAX Computer Program. This program was developed by D. B. Turner of the Environmental Protection Agency to analyze single stacks following the method described his "Workbook of Atmospheric Dispersion Estimates." # 17 TRINITY CONSULTANTS F.O. BOX 31481.DALLAS, TEXAS 75231 * VAB.OOO1126468 A bulence is inferred from the surface observations. Figure 4 illustrates the frequency distributions of wind speed and stability for New Orleans, Louisiana and Willis ten, North Dakota. It provides an idea of the relative frequency of the occurrence of various stability and wind speed combinations. New Orleans generally has less cloudiness so It has a higher fre quency of both A-, B-, and F-stability than North Dakota. For these two locations, unstable conditions exist between 14 and 25 percent of the time while stable conditions exist between 29 and percent Neutral conditions occur between 38 and J 7 percent of the time. Extremely unstable conditions, Category A, occur relatively rarely. determine stability. One relates stability to variation in wind direction The other method physically measures the vertical lapse rate on a tower or with a balloon. The termed rmined yzing the directional trace of anemometer either manually or bv use of computer averaging techniques. 3elow are two schemes for 18 TRINITY CONSULTANTS P.O. BOX 31481 DALLAS.TEXAS *5231 # Tm VAB.0001126469 FIGURE 4 QUENCY OF OCCURRENCE OF WIND tWf ED AND STABILITY COMBINATIONS Stability A B C # 4 D f E F # h Wind Speed (m/sec) calm 1-3 4-6 TOTAL .5 - 1.5 2.1 - 3.1 calm 1-3 4-6 7-10 TOTAL 0.5 - 1.5 2.1 - 3.1 3.6 - 5.1 calm 1-3 4-6 7-10 11 - 16 17 - 21 > 21 TOTAL 0.5 - 1.5 2.1 - 3.1 3.6 - 5.1 5.6 - 8.2 8.7 -10.8 >10.8 calm 1- 3 4-6 7-10 11 - 16 17 - 21 > 21 TOTAL 0.5 - 1.5 2.1 - 3.1 3.6 - 5.1 5.6 - 8.2 8.7 -10.8 >10.8 4-6 7-10 TOTAL 2.1 - 3.1 3.6 - 5.1 calm 1-3 4- 6 TOTAL 0.5 - 1.5 2.1 - 3.1 New Orleans Inter- national Airport Frequency Hours (percent) per Year 0.09 .20 1.02 1.31 8 18 89 115 0.34 1.24 4.09 3.82 9.50 30 109 358 335 832 0.32 0.57 3.57 8.02 1.43 0.05 28 50 313 703 125 4 13.95 1223 0.27 0.87 5.84 14.21 13.23 1.47 0.19 36.08 24 76 512 1245 1159 129 17 3162 6.83 5.54 12.37 598 485 1083 7.58 9.04 10.18 26.80 664 792 892 2348 Williston. North Dakota Frequency Hours (percent) per Year } Q# 26 0.14 0.40 }23 12 35 >1.00 1.73 1.09 3.82 } 88 152 95 335 >1.09 2.80 5.08 1.07 0.12 0.04 10.19 J 95 245 445 94 11 4 893 4 > 1.05 8.15 17.43 23.24 5.63 1.34 56.84 5.55 6.87 12.43 '^ _ > 5.70 10.63 16.33 > 92 714 1527 2036 493 117 4979 486 602 1089 > >499 931 1430 Period of Record: New Orleans, January, 1960 - December, 1964 Sloulin Field, January, 1967 - December, 1971 I 19 TRINITY CONSULTANTS F.O. BOX 31441 DALLAS, TEXAS 7S231 * VAB.0001126470 I classifying stability, one from Meteorology and Atomic Energy, page 102, and one from the Brookhaven National Laboratory Studies as quoted "Recommended Guide for the Prediction of the Dispersion of Airborne Effluents", published by the American Society of Mechanical Engineers (ASME).4 Meteorology and Atomic Energy Stability ASME Standard Deviation Horizontal Direction _______(Degrees) Unstable 10.5 Stable As indicated in the table, significant wind meander is expected in unstable air. Minimal meander is typical of stable conditions. The Nuclear Regulatory Commission (NRC) uses a third method to determine stability. It is specified in NRC Guide 1.23.5 Appli cants for nuclear power plants are required to erect a tower and measure temperature at two different elevations. Most towers are 50 meters high and, therefore, measure the lapse rate only in the lowest portion of the atmosphere. This is satisfactory for nuclear 20 TRINITY CONSULTANTS F.O. BOX 31481 DALLAS, TEXAS 75231 VAB.0001126471 * * applications where accidental discharges have no plume rise and dis perse within 100 meters of the ground. But such a technique may be misleading for discharges from tall stacks or from stacks having significant plume rises. Below is data taken by Louisiana Power and Light from a tower located within. 13 miles across flat terrain from the New Orleans Airport. Stability Classifications. NRC 1.23 Stability Category Lapse Rates C/m Frequency of Occurrence (percent per year) LP&L* 1.23 Method 7/72 - 7/75 N.O. Airport Pasquill's Method (from Table 4) A > -.019 14.9 B -.019 to -.017 1.7 C -.017 to -.015 2.1 1.3 9.5 14.0 D -.015 to -.005 24.1 36.0 E -.005 to .015 31.9 12.4 F .015 to .040 14.5 G > .040 10.8 }26.8 Temperature measured at 9 and 40 meter elevations One notable aspect of the NRC system is the rather narrow range of values assigned B- and C-stabilities. It appears that this was the result of an arbitrary decision by meteorologists at the NRC who Incorrectly assigned lapse rates for these categories. In the many on measured 21 TRINITY CONSULTANTS P.O. BOX 31461 DALLAS. TEXAS 75231 VAB.0001126472 the turbulence producing mechanisms. In addition, lapse rates are typically measured in the first 50 meters of the atmosphere while most industrial plumes disperse at elevations ranging from 100 to 500 meters. 22 TRINITY CONSULTANTS P.O. BOX 31481 DALLAS, TEXAS 75231 VAB.0001126473 CHAPTER II: REFERENCES 1. David H. Slade, Editor, Meteorology and Atomic Energy, U. S. Atomic Energy Commission, Oak Ridge, Tennessee, 1968. pp. 13-116. (Available as Publication TID-24190 for $6.00 from National Technical Information Service (NTIS), Springfield, Virginia 22151). 2. F. Pasquill, Atmospheric Diffusion. 2nd Edition, John Wiley & Sons Inc., New York, 1974. 3. D. Bruce Turner, Workbook of Atmospheric Dispersion Esr^tes. U. S. Environmental Protection Agency, Research Triangle rark. North Carolina, 1970. pp. 1-2. 4. Martin John R., Recommended Guide for the Prediction of the Dispersion of Airborne Effluents. 3rd Edition, American Scciety of Mechanical Engineers, New York, 1979. pp. 7-12. 5. Nuclear Regulatory Commission Guide 1.23. 2 Revised 03/81 23 TRINITY CONSULTANTS F.O. BOX 31481 DALLAS, TEXAS 73231 VAB.0001126474 1 A Plume dispersion is a problem involving fluid turbulence. Up to now the turbulence problem has resisted all attempts at a general solution. Therefore, the best present solution contains both hypothetical and empirical elements. In the final analysis, the results can only be judged by comparison with data. A. Gaussian Models Numerous experiments have been conducted to study the shape of plumes. The publication Meteorology and Atomic Energy lists over twenty experiments, many of which have been conducted by the Atomic Energy Commission (now the U. S. Department of Energy)1 In general, most investigators have been satisfied that a Gaussian distribution is a good mathematical approximation of plume behavior for periods on the order of five minutes to one hour. Although Gaussian models, properly applied, are peerless as a practical diffusion modeling tool in terms of simplicity, of flexibility and of correlations between predicted and measured values, they contain some definite shortcomings. The Gaussian distribution assumes uniform conditions in the vertical direction. In reality, the lapse rate shows changes with elevation as does wind speed. In addition, the dispersing plume will deposit material on the surface. 24 TRINITY CONSULTANTS. INC 1126475 There is, of course, much more uniformity in horizontal direction. Strictly speaking, the Gaussian equation implies an speed of propagation of pollutant physically unrealistic. Pasquill, however, has pointed out that the exact form of the tails of the distribution is not important as a practical matter. * Accuracy of Models Despite these objections, Gaussian models provide reasonable estimates in flat or gently rolling terrain. Gently rolling is v ` ^ generally described as terrain elevations of less than twenty percent of effective stack height. Turner states that the estimates provided are generally accurate by a factor of 2 (plus 50 percent).2 This is significantly less accurate than most engineering calculations or work done with computers. Meteorological Society Committee evaluated the accuracy of models and quoted Pasquill in saying that under conditions, the error can be as little as 10 to 20 * percent, but "Factor of 2 accuracy is perhaps the best that can expected in most applications of urban~scale dispersion models"3 This estimate of accuracy also underscores the need for a program should calculated values start to approach the ambient air standards. It has been the experience of most of the computer models over-predict, rather than under i 25 TRINITY CONSULTANTS, INC M3.10001126476 C. Pasquil1-Gifford Coefficients A Figure 5 The downwind coordinate system and the vertical is As a result of field studies, coefficients of dispersion m the y and z direction have been developed. Figures 6 through 9 show the Pasquil1-Gifford dispersion coefficients as a function of distance from the stack, both m graphical form from Turner and in formulas used in several EPA models.' Although these coefficients have many shortcomings. they are those in widest current use As discussed previously, nixing - and therefore diffusion is more unstable The that diffus in both the y and z direction is accentuated when the air is * unstable and minimized when the air is stable. D. Continuous Release Equations 1 ii There are four equations that are useful for estimated i ground-level concentrations. a r l t I 1 i L i 4 I J II I [ 26 TRINITY CONSULTANTS, INC i rI t k TRINITY CONSULTANTS P.O. BOX 31481 DALLAS, TEXAS 75231 VAB. 0001126479 Constants Used to Calculate a in EPA Developed Programs b DBTSIG (used in Downwind Stability (Pasouill) Distance (x) Values for o (meters) h A < *1 122.8 .9447 .1 - .15 158.08 1.0542 .15 - 2 170.22 1.0932 .2 - 25 179.52 1.1262 .25 - 3 217.41 1.2644 .3 .4 .5 > 3.11 4 .5 3.11 258.89 346.75 453.85 1.4094 1.7283 2.1166 * B < .2 90.673 .93198 .2 - 4 98.483 .98332 4 - 35.0 109.30 1.0971 >35.0 * C >123.0 <123.0 j 61.141 .91465 * D < .3 34.459 86974 .3 - 1.0 32.093 .81066 1.0 - 3.0 32.093 .64403 >3.0 - 10.0 33.504 .60486 10.0 - 30.0 30.0 - 36.650 44.053 56589 .51179 5 cm Downwind Distance (x) TEM. TCM 100 - 500 .0383 1.2812 500 - 5000 .000254 2.0886 100 - 500 500 - 5000 1393 .9467 .04936 1.1137 100 - 500 500 - 5000 5000 -123000 .1120 .1014 .1154 DAY 100 - 500 500 - 5000 5000 - 50000 .0856 .2591 7368 NIGHT 100 - 500 500 - 5000 5000 - 50000 .0818 .2527 1.2969 .9100 .9260 .9109 .8650 .6869 .5642 .8155 .6341 .4421 *The maximum calculated value for a. is 5000 neters. 29 TRINITY CONSULTANTS, INC 001126480 FIGURE 7 (Continued) DBTSIG (used in PTMTP CRSTER. BAM) Stability Downwind Distance (x) Values for a z (meters) Downwind Distance (x) E < .1 ' a 24.260 .83660 E & F (cm 6 TCM) .1 .3 .3 - 1.0 23.331 21.628 .81956 756 60 100 - 500 500 - 5000 .0545 .2017 1.0 - 2.0 21.628 .63077 5000 - 50000 1.5763 b .8124 .6020 .3606 2.0 - 4.0 4.0 - 10.0 10.0 - 20.0 20.0 - 40.0 >40.0 22.334 24.703 26.970 35.420 47.618 .57154 .50527 .46714 .37615 .29592 E (TEH) 100 - 500 500 - 5000 5000 - 50000 .1094 .2452 9204 .7657 .6358 .4805 F < .2 15.209 .81558 F (TEK) .2 .7 .7 - 1.0 14.457 13.953 .78407 .68465 100 - 500 500 - 5000 .05645 .8050 1930 .6072 5000 - 50000 1.505 .3662 1.0 - 2.0 13.953 .63227 2.0 - 3.0 14.823 .54503 3.0 - 7.0 16.187 .46490 7.0 - 15.0 15.0 - 30.0 30.0 - 60.0 >60.0 17.836 22.651 27.074 34.219 .41507 .32681 .27436 21716 I Example Calculation: PTMTP cm C-Stability 3000 meters .91465 az - 61.141(3.0) .9260 a .1014(3000) - 167.0 - 168.2 30 TRINITY CONSULTANTS, INC 10,000 4 % f r | . ri ' f ft 4 - 1 (tin .in m l1lh - l vt * *4 * t tMt! * . - _. 1 ' * 4 : -r +. i , t p. f 1. d 1 4 .'t . r- 4 * * * * * * * 4 y H t F - lift * 14 f M - 41 4 M * J J 1 1 'fl *41 ** Mltl J < 1 t til* 4 * t ft (Ml *. m. 1 ( n1 1 r n4 P - ' - p H * VI 1, k j -i 4 h 1 . h ^ . . ^H * * + rl *- r* U k. r *. b * 1- 4 b > i 1,000 b 100 A 0.1 1 10 100 DISTANCE DOWNWIND, km Horizontal dispersion coefficient as a function of downwind distance from the source. TRINITY CONSULTANTS p.o. box 31481 Dallas, texas 75231 V AR-OQfn 17.64X7. FIGURE 9 Constants Used to Calculate in EFA Developed Subroutine DBTSIG Stability (Pasquill) 1000 zb sin 9 2.15 cos 9 465.12 zk tan 9 zk downviri distance in Kilometers Value of 6 (radians) 24.167-2.5334 logo zk 57.2958 18.333-1.8096 lofe zk 57.2958 * E F 12.5-1.0857 loge zk 57.2958 8.333-.72382 log^xk 57.2958 6.25-.54287 57.2958 4.1667-.36191 loge zk (Continued on nezt page) A 32 TRINITY CONSULTANTS, INC FIGURE 9 (continued) Example calculation: C-Stability 3000 meters 12.5 - 1.0857 ln3. 57.2958 12.5 - 1.0857 1.099 _ 11.307 57.2958 " 57.2958 19735 - (465.12)(3.)(tan.19735) - (465.12)(3.)(.19995) - 279.0 Constants Used to Calculate Oy in TEM Stability (Pasauill) Downwind Distance (x) (meters) Oy ** Cxd Values for Oy (meters) cd A <10,000 .495 .873 >10,000 606 .851 B <10,000 .310 .897 >10,000 .523 .840 C <10,000 .197 .908 >10,000 .285 .867 D <10,000 .122 .916 >10,000 .193 .865 E <10,000 .0934 .912 >10,000 .141 .868 F <10,000 .0625 .911 >10,000 .0800 .884 Example calculation: C stability 908 ay - (.197)3000* 282.9 # 3000 meters l * j 33 TRINITY CONSULTANTS, INC IT m The basic dispersion equation is: (1) X (x,y ,z;H) S exp{"2(o?2fcxp 2iroyazu term a b This equation is valid if the source emits at a continuous If only ground level concentrations are of Interest then 0 and the equation becomes <2) X (x,y,o;H) iroyo2u exp { - } And if only center line concentrations are of Interest fhen the equation can be further simplified. (3) X (x,oo;H) (p 4 fcS`* iroyOzu \ If the point of release is at ground level and there is no effective plume rise 0) then the centerline concentration is: X (x,oo;o) TTOyPgU where X Q Oy z u H ground level concentration (grams per cubic meter) source strength (grams per second) 3.1416 horizontal dispersion coefficient (meters) (Figure 10) vertical dispersion coefficient (meters) (Figure 8) wind speed (meters per second) effective stack height (meters) 34 TRINITY CONSULTANTS P.O. BOX 31481 DALLAS, TEXAS 75231 VAB.0001126485 1. It is estimated that 80 grams per second of hydrogen sulfide is being emitted from an extinguished flare petroleum refinery at an average effective height meters At 8 a.m. an overcast vinter morning vith the surface wind of 6 meters per second, vhat is the ground level concentration directly downwind from the refinery at a distance of 500 meters? o > SOLUTION: Use equation 3 X 80 ir(36.1) (18.3)6 exp Ql So 60 2 18.3 6.42 x 10-3 [- ~2 (3` 28) 2 /8-i SfsJs/i JLi (o - i (3.28)2 \ (10.75) -5.37 1 b. s / 1 216 6.42 X 216 10 -6 29.7 x 10 grams/meter3 * 30ug/m3 A 35 TRINITY CONSULTANTS, INC 01126486 PROBLEM B 2. Under the conditions of problem 1 what is the concentration at the same distance downwind but at a distance 50 meters from the x-axis? That is: X(500, 50, 0: 60) - SOLUTION: Use equation 2 and calculation made for Problem 1. X * 33 x 10 6 exp 2 X - 29.7 x .3835 * 11.4 pg/m3 36 TRINITY CONSULTANTS, INC. VAR.O 487 E. Description of Fuff Release The dispersion of a puff can be described in Gaussian terms just as the continuous release. In a continuous model the plume disperses in the vertical (z) and horizontal cross wind (y) direction. In a puff model the dispersion takes place in the z,y and downwind (z) direction. The calculated concentration is the peak instantaneous concentration and it is independent of wind speed. When a release occurs the gas forms a spherically-shaped cloud 4 just above the point of release. The concentration in the cloud is highest at the center. The cloud then is transported by the wind growing in size as it entrains ambient air. The growth of the cloud and its movement can be compared to a balloon that gradually inflates as it is moved by the wind. The mass of the gas in the cloud does not change as the cloud moves downwind, but its concentration does, as more ambient air is entrained. Sometimes the release is not instantaneous but takes place over a period of several minutes such as when gas in a cylinder leaks out or during the interval between the time a leak in a valve is discovered and it can be stopped. In cases such as these the cloud may become somewhat elongated and look like a blimp or a hot dog. By assuming an instantaneous release a puff model will overestimate peak concentrations, but it will have no effect on average concentrations provided the averaging time is long enough. 37 TRINITY CONSULTANTS, INC VAB.0QQH26488 F. Puff Model Dispersion Coefficients The EPA puff model uses dispersion coefficients developed by studying instantaneous release.6 These coefficients generally provide for less plume dilution than the familiar Pasquil1-Gifford coefficients. The table shows the dispersion coefficients. Figures 1 and 2 plot the coefficients on a diagram of the Pasquil1-Gifford coefficients. Coefficient " ax where x is downwind distance in meters A 1 I i ! Stability Unstable Neutral Very Stable Horizontal (x and y) ab .14 .06 .92 .02 .89 CM 0% Vertical <z) ab .53 .73 .15 .70 .05 .61 Since the dispersion in the x and y direction are generally considered to be equal, some authors refer to the standard deviation in the horizontal as or (r for radius). I 38 TRINITY CONSULTANTS, INC 10,000 Figure 4.0 [^*1*( 4 t M f* 4|j 4 *2*iFTTTT Li't * t H i * * - jf 4 j|j#T 4 * * * TTT3FTTfT * * JrJ1*4** * jm 4 J[f *i * 1f 4 4 *> 4 Horizontal dispersion coefficient as a function of downwind distance from the source 39 TRINITY CONSULTANTS P.O. BOX 31481 DALLAS, TEXAS 7S231 V AB-OmQsCmn 1:26490 wmmm 1,000 too b t 4* 10 1 in gure 1 1 10 DISTANCE DOWNWIND, lun too Vertical dispersion coefficient as a function of downwind distance from the source. 40 TRINITY CONSULTANTS p.o. box 31481 Dallas, texas 75231 6. Average Concentrations from Puff Releases The function of vind speed. For example, a vind of 10 knots vill transport twice as much air knots The average concentration is a function horizontal direction (sigma-x or sigma-r) that pass a given point for the averaging time in question. At long downwind distances and low vind speeds the average concentration will not be much less than instantaneous The puff has become so dilute possibly less than one sigma passes a point averaging time specified. At the other extreme there is a significant difference between and peak instantaneous This is because the puff is sma in dimension and most materia1 very concentrated puff. Figure 1 pipeline break. disperse from a 41 TRINITY CONSULTANTS, INC VAB.OQM'126492 Figure 12 A UJ CO < 111 Ui a: u u. o o Uuf -- o N0li.VUJ.N30 NOD 42 VAB.0001126493 Figure 12 (cont'd) LJ co < U. < CO 111 * DISTANCE NOIJLVdlNBO N00 43 VAB.0001126494 LU tn < 11 < CO UJ figure 12 (cont'd) A Q N0I1VM1N30N00 N * * T MHI 4 4 VAB.0001126495 H. Puff Equations The basic equation is: e0't i+f x _____ _S_____ (2ir) l* o-xCyZ crj rp{-?e=9_) + exp {-i 2}} * Note that Q is quantity in this equation, not a release rate* t/s a peat instantaneous concentration, not the average cone "ration. A ailrt* X- 3^- peak instantaneous concentration (grams per cubic meter) Q Source strength (grams) IT 3.1416 X horizontal downwind dispersion coefficient (sieters) (This value is often set equal to ) y vertical dispersion coefficient (meters) (meters) H effective stack height (meters) I. When to use Puff or Continuous Release Models The puff model should be used cloud J if the release travel time of the cloud. For example, minutes. then would be appropriate to calculate concentrations at receptors beyond a 10-minute travel time using a puff model. For receptors within a lO-mincte travel time distance it would be appropriate to use a puff model based on the release of a series of puffs at intervals cf, say, o minute release model such as PAL or ISCSI. -o TRINITY CONSULTANTS, INC I* VAB... Answer Sheet Problem C imated emitted fro an extinguished petroleum effective stack height of 60 meters. At 8 a*m. on an overcast winter meters per second, what is the peak instantaneous concentration at a distance of 500 meters from the and distance? Time 83.3 seconds minute 2. Peak concentration: Q 4800 y .06(500)-92 18.25 .15(500)70 11.62 20 * (2n) 1 s--y2 z ' \2 1H 2a 2 x 4800 x 106________ 1 f 60 ] 2 X (15.75) (18.25)^11.62) exp ~2 hi.62* (157492) exp-13.331 a A 0.256 Ug/m 3 A 46 TRINITY CONSULTANTS, INC WcBtfOO1126497 CHAPTER III: REFERENCES 1* Slade, op* cit. pp. 117-188. 2. Turner, op. cit. pp* 5-10. 3. "Accuracy of Dispersion Models," Bulletin of the American Meteorological Society. Volume 59, Number S (August, 1978) p. 1025. 4. U. S. Environmental Protection Agency, UKAM4P Series of Dispersion Models. Data derived by examination of coded data in program. 5* Adrian D. Busse and John R. Zimmerman, "User's Guide for the Climatological Dispersion Model," U. S. Environmental Protection Agency publication number EPA-R4-73-024, Research Triangle Park, North Carolina, 1973, p. 8. 6. Slade, op. cit. p. 120, p. 173-175. 47 TRINITY CONSULTANTS, INC. IV. Initial Cloud Site and Building Wake Effects. A. Accounting for Initial Cloud Size SLarely is the source a point. a Instead a cloud of finite dimensions is formed. For example, a cylinder in a gas cabinet 4 nay break. The cylinder contains 165 cubic feet of 90 percent hydrogen and 10 percent arsine. Tha ventilated gas cabinet has a volume of 83 feet. Thus a dead containing the arsine will have a volume before dilution in the atmosphere of 248 cubic feet of vhich 16.5 cubic feet vill be arsine. The initial concentration of arsine is 66,500 ppm and 248 cubic feet would i occupy a sphere with a diameter cf 2.38 meters at 68*F. The cloud in already 2.38 meters in the i,y and z direction before it leaves the point of release. The standard deviation is calculated by dividing the horizontal extent of the cloud by 4.3 and the vertical extent of the cloud by 2.15. The ajprtpriate way to adjust spers andard deviation cf the cloud dimensions to the standard deviation calculated from the dispersion coefficients. y V \jy T yo 2 + azo - A I i v I a Subscript for adjusted sigma values Subscript for sigma values at origin Xu a Gaussian cloud the material is assumed t: be distributed in 48 TRINITY CONSULTANTS, INC VAB.0001126499 a Gaussian fashion. In dispersion modeling the concentration at the edge of the cloud is assumed to be 10 percent of the central value. Statistically speaking, the cloud is 4.3 standard deviations vide. Within this area 96.48 percent of material is contained. The average concentration across such a cloud is: r ...* (4.3)(.3989) 0.5625 of the value at the center of a.two dimensional Gaussian curve What really happens is that instead of having a sphere of uniformly mixed gas 2.38 meters in diameter, there is a cloud vith a gaussian distribution of contaminants. At the center of this cloud the concentration is 66,500 ppm. The mathematics to convert the tvo dimension values to three dimensions are complex. The equivalent gaussian sphere vith a diameter of 4.3 standard deviation is about 2.04 times the diameter of a cloud containing uniformly mixed gas. In the example the diameter of the cloud is 4.86 meters. Sigma y is 1.13 meters and sigma z is 2.26 meters. When using computer programs that request a user-supplied dimension of the initial cloud size, it is best to estimate the initial sphere size and then adjust it in the manner described above The degree of accuracy in estimating the initial cloud size can make a significant difference at receptors close to the source, those vithin a fev hundred meters. At greater distances 49 ---------- TRINITY CONSULTANTS, INC__________________ atmospheric turbulence dominates dispersion and rarely does the initial cloud size have much effect on concentrations at distances beyond one or two kilometers* B. Virtual Distance Method -P Instead of making detailed calculations of initial cloud size, a computer program can be written which will calculate a virtual distance* The virtual distance will be added to the actual downwind distance for the purpose of determining dispersion coefficients * The virtual distance is the distance a puff would have to travel for atmospheric turbulence to dilute it to a concentration equal to the initial center--of-cloud concentration calculated. Usually a computer program iterates up--wind in 1 or 10 meter increments until the virtual distance is too great then reverses direction and iterates in 0.1 or 1 meter steps to find the correct distance* The initial concentrations are most known in terms parts per million (ppm). If a pure gas escapes the concentration at the center of the cloud is 1,000,000 ppm. But the model is designed to calculate concentrations in grams per cubic meter A calculation must be made olecular weight, temperature and pressure to relate ppm to grams per cubic meter. 50 TRINITY CONSULTANTS, INC. VAB In the example in Chapter II, the initial concentration vac 66,500 ppm of arsine (molecular weight 77.9). If this release were to take place at 77F and at sea level, the concentration would be: 77.9 X 1013.2 x 66,500 X 298.16 x .0831 211.8 grams per cubic meter Under neutral conditions the virtual distance is calculated to be 29.3 meters. The sigma x and sigma y value is 1.342 meters and the sigpa z value is 1.596 meters. Conversion of Concentration Units Concentrations are usually expressed in a volume ratio such as ppm or in a weight per unit voluste such as micrograms per cubic meter. The equation to convert concentrations is: x(yg/m3) x T(K) x R M x P(mb) where: * T Absolute temperature (K) R Gas constant (mb m3/gm-mol K) M Molecular weight (gm-mol) P Atmospheric pressure (nib) 298.16 0.0831 1013.2 Standard conditions are defined in 40 CFR50.3 and are noted to the right of the definitions. X (ppm) .02445 M X (ug/m3) 51 . TRINITY CONSULTANTS, INC 4 --------V Increases m altitude reduce atmospheric pressure and result in increases in concentrations expressed in ppm. The table below summarizes values for various altitudes: Altitude (feet) 0 2,000 4,000 6,000 8,000 10,000 D. Obstructions Atmospheric pressure (mb) 1013.2 942.1 875.0 812.05 752.45 696.9 Molecular veight where ppm equals micrograms per cubic meter .02445 .02630 .02832 .03051 .03293 .03555 4 * t 4 i T 1 * t [ I 4 / If a cloud or plume is traveling downwind and it encounters an obstruction such as a building the cloud will generally flow around the building. In flowing around the building the cloud grows in size so that it is as large as the building. Other disturbances that can cause the cloud to grow include automobile traffic on a road or a complex open structure such as structural steel supports of process units at a chemical plant. This phenomenon suggests that as obstructions to wind-driven flow increase, the greater the probability that the cloud will become diluted. In 1977 and 1979, Alan Huber of the U.S. Environmental Protection Agency published the results of extensive wind tunnel investigations. The conclusions of the study were that the wake 1,2 could be divided into three areas: 52 ----------- TRINITY CONSULTANTS, INC. r*r A Downwind Distance (x) Divided by Height of Building (Hb) Zone I Zone II Zone III 3. ,3. to 10 10 The building studied was twice as long as it was high, representing a typical type of structure* The vertical dispersion parameter for stack heights less than the sum of H + 1.5H in Zone II was determined to be: 0.7H + 0.067 (x - 3HU) DD Cy 2 + 0.067 (x - 3Hb) where: Hv * width of building perpendicular to the wind Figure 13 illustrates the growth of the wake. IS determined by dividing the wake The value for Oy w The a 2I is determined by dividing the half For Zone III calculations, an enhanced dispersion parameter can be estimated using a virtual displacement. Tae plume widths are estimated based on moving the source somewhat further away from it8 actual location. .i 53 TRINITY CONSULTANTS, INC T VAftrSeOT 126504 Figure 13 A Hw Should Not Exceed 5 Hb GROWTH OF WAKE VAB.0001126505 O'z m (x + Sz ) 4 where: Sy is the virtual source distance such that a^(lOHb) - 0.7 ft* /2 +0.46Hb . Sz is tte virtual source distance such that aJUO^ ) - 1.167^, . If the building is taller than it is wide, substitute % for % in the calculations of both Oy and &z . An example will clarify the calculations: s * Assume a building 15 meters in height, 50 meters in width, D and Downwind Distance Multiple of Meters 45 3 75 5 150 10 300 328 478 1000 20 67 Wake Area &2 Or 17.5 19*5 24.6 34.7 36.5 46.2 79.1 10.5 12.5 17.6 21.9 22.8 26.8 39.4 Undisturbed Flow m2 Oi!2 i 3.9 6.3 11.9 2.3 3.6 6.6 22.6 24.6 34.5 68.1 12.1 13.0 17.6 32.1 55 TRINITY CONSULTANTS, INC n At 150 meters (10 characteristic dimensions) downwind Oy * 24.55 meters which is the same oy as undisturbed flow for a downwind distance of 328 meters. The virtual distance for calculation is m is 178 meters (328 less 150 meters). the In the wake a' for 300 meters downwind is based on the width of undisturbed flow at 478 meters. For 1000 meters it is based on 1178 meters. The a should not be adjusted if the stack height is greater than 1.2Hb according to Huber. At 150 meters o' is 17.55 meters which is the same width as undisturbed flow for a downwind distance of 475 meters. The virtual distance is 325 meters The al for 300 and 1000 meters is determined from the oz for 625 and 1325 meters respectively. Huber recommends ignoring the horizontal dispersion parameter enhancement if the stack height is greater than 1.2H^ This algorithm for wake effects is included in the following computer models: ISCST, ISCLT, TEM8 and TCM2. 56 TRINITY CONSULTANTS, INC. CHAPTER IV: REFERENCES 1. Alan H. Huber. "Incorporating Building/Terrain Wake Effects on Stack Effluents", presented at Joint Conference on Applications of Air Pollution Meteorology. November 29 - December 1. 1977. Salt Lake City. Utah* 2. Alan H Huber. "An Evaluation of Obstacle Vake Effects on Plume Dispersion", presented at American Meteorological Society. Fourth Symposium on Turbulence. Diffusion, and Air Pollution. January 15-18. 1979. Reno. Nevada. 57 TRINITY CONSULTANTS. INC T V. Effective Stack Heights In order to calculate ground-level concentrations, the effective height of emission must be known* The diffusion experiments described in the previous chapter all oriented the source of tracer material in the horizontal position and emitted material at ambient temperatures.* This sidestepped the practical problem associated with industrial stacks of plume rise due to momentum or thermal effects. The simplest way to calculate effective stack height is to add physical stack height to the observed or calculated plume rise: H - h Ah Where: H is effective stack height h is physical stack height Ah is plume rise Some confusion centers on the meaning of plume rise. Ideally it is the elevation above the stack top of the centerline of a plume traveling in a horizontal direction. The only difficulty, according to Briggs, is that in more than 90 percent of the recorded observations the plume had not yet become level when it was no longer visible. Measured plume rise is strongly a function of measuring technique. Plumes dispersing in stable or neutral atmospheres are relatively easy to measure. Those under unstable conditions are nearly impossible to measure accurately. 58 TRINITY CONSULTANTS, INC. T To overcome this problem Briggs suggests that plume rise be defined as the difference betveen stack height and the effective stack height one would need in the diffusion equation to correctly calculate the maximum ground-level concentration.1 Plume rise is both a function of momentum and buoyancy* Terms related to one or both factors are included in all plume rise formulas* For cold stacks, those with emissions of less than 5 to 10C* above ambient, momentum is probably the most important* For hot stacks (those warmer than about 50C) buoyancy, due to the light weight of hot gases, is the most important* Caution should be used on stacks where the emissions include moisture droplets As the water in the plume leaving the stack vaporizes, it requires heat of vaporization which quickly cools the diluting stack gases* Under conditions of low humidity this can cause the plume to fall to the ground rather than rise* This condition is often visible on cooler days* Over the years more than 100 plume rise formulas have been proposed by over 50 groups of investigators according to Briggs* For the most part, these investigators limited their studies to specific stacks* Many also studied plume rise under a limited range of conditions* Although there has been widespread disagreement within the environmental community regarding the accuracy and appropriateness 59 TRINITY CONSULTANTS, INC. 5510 of dispersion modeling there has been virtually no challenge to the plume rise formulas developed by Briggs. These formulas are incorporated in all EPA models and are appropriate in modeling puff releases. A. Briggs' Buoyancy Formula In 1969 Gary A. Briggs, then an employee of the Atomic Energy Commission, made very thorough study of the available plume rise equations Figure 14 is taken from Briggs' vork3and it compares calculated and observed values for selected formulas. Briggs vent on to study plumes, most of them from coal-fired power plants, in much detail than previous He then proposed his own Following a detailed evaluation of Briggs' original work and two subsequent modifications, the Environmental Protection Agency adopted his equations4. 5 Briggs' equations have been recommended in place of Holland for calculating dispersion following Turner's Workbook of Atmospheric Dispersion Estimates starting 9 with the sixth edition, published in December, 1972. A 60 TRINITY CONSULTANTS, INC FIGURE 14 Comparison of Calculated Values with Observations for Neutral Conditions I ----^ C* ^ ^ O ^ 4 * i + m I4 9* 9^ N sO O 00 O* m3C Oo' < <Nto *O m +mc1m c--m +1 O>C0 f'/>l r* cm* --CM cOm' --*o om 4^ mO o-- SO* ^ . oHe H no ^r*0 co rm* ox one +C1M g-CHM 0*0 _* O*' Cn ^ r n w* rs -- -- rMcm cm****# 0 0 mCdM CmoM ^t o CVM) d 90 d mo w t odd v; v) c' *--- vdC ' ^ v>* mr* ^'cOm +1 +i cCm hO' X^ OOO & ** OOcoOO'oOO m--clOd'Om--'CoCdO* CM CM H -H 9^ CM v^> o* xMc^ix^r-ci R -- ooooooo0 I * 4 t I* o jo jo jn m O' --O' --O' mO' mO' OO' ^Od' f*oCr> dsO md dr<0i +*# +i O Ka sa 5S . = 3? 8 ;* =Oa O a a! n 22 61 TRINITY CONSULTANTS, INC I 4 Tf :i rv <o H J<Z B riggs la te r s u b s titu te s 1.6 fo r 1 .8 , a re d u c tio n o f 11 p e rce n t. PLUME RISE EQUATIONS For neutral and unstable conditions (stability categories A, B, C and D) at distance x downwind 1.6F-333(x).667 Ah u For final rise Ah _ 21.425F-75 u Ah 38.710F-6 u F < 55 F > 55 Final plume rise is achieved when the downwind For final plume rise under stable conditions ( F .333 Ah 2.6 (--us) Where F T ir (1 - Ts ) X* 14F-625 where F < 55 X* 34F- ** where F > 55 8 & (ii) T 60/6z Vertical potential temperature gradient in the atmosphere E category F category 02 K/m (stable conditions) 035lC/m (stable conditions) F buoyancy flux (m4/sec3) Ah plume rise above stack top (m) u wind speed at stack level (m/sec) X horizontal downwind distance (m) X* 3.5x* horizontal distance from the stack at which atmospheric inate entrainment distance to point of final rise for unstable S gravitational acceleration 9*8 m/sec2 T ambient air temperature " 293K (usually) stack gas temperature (K) Vf stack gas volume flow (m3/sec) A Revised 7/85 62 TRINITY CONSULTANTS. INC 1126513 In some lectures Gary A* Briggs has commented on the shortcomings of his widely used formula for plume rise. 1 Buoyancy Flux The Briggs' formula assumes that the stack gases have a molecular weight similar to that of air For fue 1 combustion sources this assumption is accurate within five The products of natural gas combustion have a molecular weight of about 27.5 which is slightly lighter than air because of the water vapor formed from the combustion of hydrogen. The products of coal burning have a molecular weight of about 30* which is slightly heavier than air because of the large amount of carbon dioxide. As a practical matter, nitrogen nearly always dominates the composition of stack gases so that molecular weights significantly different from air are rare. 3 A i On the other hand, an incinerator burning hydrogen sulfide or one emitting chlorine compounds does not have the same weight as air and some adjustment may be appropriate. The term (1 - T/T ) reflects the buoyancy of the heated gases. It is this term in the buoyancy flux, F, that can be modified to account for differences in the molecular weight f of the stack gases. 63 TRINITY CONSULTANTS, INC___ VAB.0001126514 F r o- - 28.9TS ) where wm* molecular weight of stack gases When using computer models which don't allow entry of molecular weight, it is often easier to adjust the stack temperature for the molecular weight difference. Trinity Consultants recommends adjustment attempted if the use of routine plume rise formulas results which are quite different than observations* 2 Wind Speed The wind speed in the various formulas should be the line of the plume Some program speed for the height of the stack top. Then for each incremental plume rise, the wind speed was recalculated until final plume rise was determined. It turned out that if one made an appropriate adjustment for the wind speed at stack top. then it wasn1t adjustments. cessary to make the incremental The CDH, BAM, TEM, TCM and CRSTE& programs make adjustments for higher average wind speed at the top of the stack compared to anemometer height. PTMAX, PTKTP and VALLEY programs do not make wind speed adjustment, but this may 64 TRINITY CONSULTANTS, INC. VAKUOOl126515 may not be a flav depending on hov these programs are used If the programs are being used to calibrate a model, then it is likely that correction for the higher speed winds aloft than those measured at the surface is appropriate. If the m program is being used to forecast worst case, then assuming a uniform vertical wind field may be better. Restoring Acceleration In the plume rise equation for stable air the "potential lapse rate" represented by the term 56/6z is used. This is assigned a somewhat arbitrary value by EPA in their odeIs. Briggs suggests that when evaluating a specific site the i restoring acceleration value should be the difference between the adiabatic lapse rate (-0.01C/meter) and the actual lapse rate from the top of the stack to the plume centerline, not the lapse rate close to the ground. In other words: 66/6 AT/ah 0.01 Where: AT is the air temperature difference between the plume centerline and the top of the stac Ah is the plume rise in meters. In all EPA models z is assumed to be 0.02 and 0.035C/m for E- and F-stabilities respectively. These values are typical TRINITY CONSULTANTS, INC. --------------- t values in the lovest 50 meters of the atmosphere. At higher elevations it may be more appropriate to use lover values because the lapse rate vill tend to become more adiabatic. For tall stacks on a power plant, a value of 0.01C/meter is probably more appropriate. 4. Size of Plants The Briggs formulas have generally been validated for plants vith an approximate fuel consumption greater than 200 X 10 BTU per hour or roughly 34 cubic meters per second of stack gases at about 300F (422K) assuming fuel oil combustion and 30 percent excess air. The use of Briggs formulas for L smaller stacks is often done, but there is an absence of validation on these smaller stacks. Among other things, it appears that the coefficient for the stable plume rise is less (about 2.4) for smaller stack and greater (up to 3.1) a for larger stacks. B. Plume Rise of Flares Flares are incinerators that bum waste gases in the open atmosphere. Typically, a flare is a vertical stack through which waste gas, and sometimes fuel gas, is emitted to the atmosphere. At the top of the stack the mixture bums in the atmosphere. The flare tip is often equipped with an automatic device to keep the flare lit. It is also often equipped with a steam line. The steam acts to make the flare "smokeless." 66 TRINITY CONSULTANTS, INC Host sed for the emergency release of process gases during upsets Thus emissions from flares are rarely included in emission inventories and are rarely modeled, except fcr the annual rate of emissions. p exception is the natural gas processing industry which u An large number of continuous flares for disposing of acid gases (hydrogen sulfide and carbon dioxide) from the amine plants used to "sweeten" the gas. Flares tend to be very efficient in converting hydrocarbons to products of combustion. A study was performed by Engineering Science, Inc. in 1983 and jointly sponsored by the Chemical Manufacturers Association and the United States Environmental 7 Protection Agency. This study reports that "when flares are operated under conditions which are representative c industrial practices, excluding emergency releases, he combustion efficiencies in a flare plume are greeier than 98Z." The Briggs' buoyancy plrme rise formulas can be easily adapted to forecast the plume ris* fron flares. These formulas require parameters that are ccsmcnly available such as the stack temperature and the volumetric flow the stack. From these values the user calculates buoyancy flux, F, which is equal to the heat release of the stack. If manual calculations being made, F can be calculated knowing the volume and heat content of the gases beiu flared. But if a computer is being used, it is often easiar to first calculate F, assume a stack temperature and calculate synthetic volumetric -j TRINITY CONSULTANTS, INC. flow 0112( This latter method permits one to use all existing EPA computer programs to analyze flares. 1. Calculating F from Heat Release Briggs states the following equivalencies in Equationas 4.19c and 4.20. F - gvr2(l - *) - - 3.68 X 10-5QH A where: F buoyancy flux parameter (m4/ec3) g gravitational constant (9.8 m/sec2) v stack velocity (m/sec) r stack radius (m) density of air (1205if/m3) density of stack gases heat release (low heat value) (calories/sec) specific heat of air (0.24 calories/g K) ambient air temperature (usually 68#F * 20C 293 K) stack gas temperature ( A) volume of stack gases at standard conditions volume of stack gases at stack conditions The equation on page 57 of this manual is: TT (1 The equality between equations (1) and (2) can be demonstrated is proportional to rTr- and Vf 7rr2v. p Thus, F " gvr 2 (1 - *) TT (3) The heat release is the product of the volume of gases, the specific heat per unit volume and the temperature change. The specific heat of gases is given in units per weight so 68 TRINITY CONSULTANTS, INC VAB.0001126519 one must multiply tiis by the density to get specific heat per unit volume* A value for V can be calculated and substituted in equation (3)* QH - VC^CTg - T) (4) substituting stsck conditions: y Vf--T ^8 Qh - Vf^o^(T, - T) (5) rewriting to get an equations for Vf : substituting this value for Vf in equations (3) i irCppT The usual problem is to intemix flare stacks with conventional stacks* In the usual form of Briggs* plume * rise equation* best release is calculated from stack temperature and the volumetrie flow rate of the stack* For a flare* heat release is knoim, but in order to intermix flares vith conventional stacks* a stack temperature is assumed and an equivalent volumetric flow rate determined* 69 ---- TRINITY CONSULTANTS* INC. VAB.0001126520 Trinity Consultants usually makes the following assumptions rt and then substitutes in equation (6). T - 68F - 20C - 293 K Cp 0*24 cal/gramK p 1205 gram/m3 Ts - 1000K QH 1000 0.24(1205X293) 1000 - 293 16.7 X 10"5Qh A Although the products of combustion usually have a higher specific heat than air and are heated first, these products become rapidly diluted with ambient air. Hence the specific heat of air should be used for calculating plume rise. m through infrared radiation is a function of the surface area and the fourth power of the absolute temperature of the hot a gas envelope* If the flame is burning smoothly, and m turbulence is at a minimum, then a higher radiation loss vill occur* As turbulence increases, due to either the nature of the gas discharge jet or vind, the radiation loss * decreases* This is a result of a higher rate of dilution and a smaller hot gas envelope* Judgment should be used to determine the amount radiated heat* In order not to underestimate radiation and therefore overstate plume rise. Trinity Consultants assumes a 20 percent loss* This means that 80 percent of the heat of * combustion is used to heat the products of combustion* 3* Effect of Addition cf Steam Steam is often used to make a flare "smokeless*" High pressure steam is throttled through nozzles into the area of combustion. If the nozzle vere perfect, then the flow would be isentropic (constant entropy)* Most nozzles have an efficiency of between 87 and 92 percent* + Trinity Consultants assumes that 90 percent of the enthalpy loss at isentropic (constant entropy) conditions occurs and from this calculates the enthalpy at the nozzle outlet* This is compared to the enthalpy of water vapor at standard conditions and the difference subtracted (or added) to the 71 ----------- TRINITY CONSULTANTS, INC____________ --^ * beat of combustion This can be illustrated with schematic Mollier chart. a In the example shown in Figure 15, the steam to the flare has a pressure of lOOpsia and 500F. Its initial enthalpy is 1279 BTU per pound* If the nozzle were perfect the change would take place at constant entropy and the final enthalpy would be 1117 BTU per pound* The discharge steam would contain 3*5 percent water vapor* Because of the inefficiency of the nozzle only 90 percent of the enthalpy loss takes place (to 1133), and entropy increases somewhat* The discharge stream contains 1.8 percent water* Since 970 BTU*s are required to convert each pound of water to steam, 17 BTU*s (970 times *018) must be supplied per pound of steam by the combustion of the flare to vaporize the water formed* The heat content in fuels is described by two numbers, the high heat value and the low heat value. The difference between the two is that the high heat value includes the heat of vaporization. Low heat is the high heat value less the heat required to vaporize water formed during combustion* Between the point of formation of water vapor to ultimate plume rise of a flare, water is rarely condensed. Therefore, as a matter of being conservative, the use of the low heat value is recommended. 72 TRINITY CONSULTANTS, INC. FIGURE 15 ENTHALPY 1279 SATURATION LINE 1132.8 1116.5 ENTROPY, s 73 TRINITY CONSULTANTS ?.0. BOX 31481 DALLAS, TEXAS 75231 "TT 126524 PROBLEM E: An acid gas stream of the following composition is being sent to a flare. No fuel gas is being used: Methane (CHi+) Ethane (C2Hg) Propane (C3H8) Other (C4+ ) Hydrogen Sulfide (H2S) Carbon Dioxide (C02) Nitrogen (N2) % by volume 1.97 .55 .41 .68 43.40 52.84 *15 100.00 The measured flow rate is 452,000 cubic feet per day measured at 60F at 14.65 pounds per square inch pressure. No steam or fuel gas is being used. The first form is used to correct gas flows from measured conditions (which vary widely) to standard conditions. The second form calculates the effective heat release (Qh) and the equivalent CALCULATION OF VOLUME WASTE GAS FLOW RATE .3139 103 CF/MIN. AT. STD. CONDITIONS FUEL GAS FLOW RATE103 CF/MIN. AT STD. CONDITIONS F psia 60 F 14.65 psia TO CORRECT FUEL GAS FLOW RATE: RATE AT 60-F, 14.65 psia gg-j-fg x - 1.012 page 1 of 2 HU MM VAB.0001126526 A CALCULATION OF HEAT RELEASE FUEL c2h6 C3H8 C4+ CO h2s 103 CFM BURNED LOW HEAT VALUE 103 BTU PER CF AT 68F 14.7 PSIA HEAT RELEASED 106 BTU/MIN .006 .002 .001 .002 .138 .896 1.594 2.282 *3.000 .316 .560 .005 .003 .002 .006 .077 4 TOTALS HEAT RELEASE FROM COMBUSTION .093 106BTU/MIN PORTION OF HEAT USED TO HEAT PRODUCTS OF COMBUSTION .80 (Usually .80 or greater) NET HEAT RELEASE (Q,,) .0744 10^BTU/MIN x - I !ll2 H ----------------- 60 I----------- 252 Calories m 1 BTU 60 Seconds m 1 Minute 106CAL/SZI Using an assumed stack temperature of 1000K (1340F) _6 V - 16.7 x 10 Q 1 5-22 Tm PP page 2 of 2 VAB.0001126527 c. Briggs' Momentum Formulas Since 1967 there has been considerable research done on the plumes from sources vhere momentum, not buoyancy, is the F principal source of rise* Briggs proposed these formulas in 1971 and they are used in most of the never models. In these models, the plume rises are calculated by adding the buoyant rise to the momentum rise. The greater of the tvo values is then used for further calculations. The formulas used are as follovs: 1.667 Unstable: Ah v2d 1.89 u(v + 3u) X .333 Stable: Ah (max) vd u Ah(max) - .945(vd)-667u",333s-*167 Where: x downwind distance (m) V stack exit velocity (m/sec) u wind speed (m/sec) stack diamter (m) JL ! T dz g " gravitational acceleration (9.8) m/sec2 T ambient air temperature (293X usually) 36/3 a " vertical temperature gradient in the atmosphere. Both EPA and Texas assume: E-stability category F-stability category .02C/m 035C/m 77 TRINITY CONSULTANTS, INC * 26528 is reached rather rapidly so the use of the final plume rise formula rarely results in an error* questionable the gases from short vents on buildings enter a stable atmosphere* The atmosphere in the immediate vicinity of buildings, especially in industrial areas is more likely to be neutral than stable* 78 TRINITY CONSULTANTS, INC CHAPTER V: REFERENCES 1* Gary A. Briggs, "Plume Rise Predictions," Chapter 3 in Lectures on Air Pollution and Environmental Impact State ments, American Meteorological Society, Boston, 1975* pp. 59-111. 2. Turner, op. cit. p. 31. 3. Briggs, Plume Rise, op. cit. p. 45. 4. Gary A. Briggs, "Some Recent Analyses of Plume Rise Obser vations," Proceedings of the Second International Clean Air 2SE&s, Academic Press, Hew York, 1971. pp. 1029-1032. 5. Gary A. Briggs, "Discussion on Chimney Plumes in Neutral and Stable Surrounding," Atmospheric Environment. 6 (July 1972). pp. 507-510. " __ F 6. Gary A. Briggs, a taped lecture contained in "Effective Stack Height/Plume Rise," U.S. Environmental Protection Agency, 1974. (Available as Course Ho. SI 406 from National Audiovisual Center, Order Dept. (GSA), Washington, D.C. 20409). 7. Chemical Manufacturers Association, "A Report on a Flare Efficiency Study" March, 1983. 79 TRINITY CONSULTANTS, INC a VI* Toxicological Considerations A* Chronic and Acute Toxicity Chronic toxicity refers to long term effects on the human body* Chronic effects are usually estimated using annual average models* Acute Time toxicity refers to short ten ranging from a few seconds human to 30 minutes are generally of interest when studying acute effects Section 112 of the Clean Air Act requires EPA to develop regulations for hazardous air pollutants. The term hazardous air pollutant means "an air pollutant to which no ambient air quality standard is applicable and which in the judgment of the Administrator causes, or contributes to, air pollution which may reasonably be anticipated to result in a increase in mortality or an increase in serious irreversible, or incapacitating reversible, illness." Under has continuous releases of chronic pollutants such as asbestos, ^^yl chloride, benzene, a cry Ion 2. trite and similar compcunds* The EPA ha8 not employed probability estimates for episodic pollutant human large concentration of some of but g terms effects will be rather small example of such an air contaminant* Vinyl 80 TRINITY CONSULTANTS, INC A8 On the other hand some compounds are dangerous in high concentrations for brief periods of time but relatively harmless m lower concentrations Hydrogen sulfide generally concentrations exceed 1000 ppm for 5 linutes but the workplace standard allows values of 10 ppm for an 8-hour work day* Because each chemical compound has different short and long term effects, it is suggested that a toxicologist be consulted to establish safe acute toxicity levels for exposure* The appendix contains a sample report prepared for arsine* * B* Air Contaminant Limits in the Work Place The most comprehensive set of suggestions is published annually by the American Conference of Governmental Industrial Hygienists (ACGIH)*l The 1968 version of this publication forms the basis for the Occupational Safety and Health Administration (OSHA) rules affecting air contaminants 29CFR1910.93.2 It also is used by various state agencies. One example is "Airborne Contaminants" published by the State of California, Department of Industrial Relations (GAL/OSHA). The ACGIH publication contains four columns of data for each substance* The time weighted average (TWA) and The Short Term Exposure Limit (STEL) are shown in terms of ppm and milligrams per cubic meter. 81 ---------- TRINITY CONSULTANTS, INC. t The TWA is defined as follows: "The time-weighted average concentration for a normal 8-hour work day and a 40-hour work week, to which nearly all workers nay be repeatedly exposed, day after day, without adverse effect." The STEL is defined as follows: "a 15-minute time-weighted average exposure which should not be exceeded at any time during the work day even if the eight-hour time weighted average is within the TLV. Exposures should not be longer than 15 minutes and should be repeated more than four times per day. There should be at least 60 minutes between successive exposures to the STEL. (It is a) concentration to which workers can be exposed continually for a short period of time without suffering from: 1) irritation, 2) chronic or irreversible tissue change or 3) narcosis of sufficient degree to increase the likelihood of accidental injury, impair self-rescue or materially reduce work efficiency." For the great majority of substances with a TLV, there is not enough toxicological data available to warrant a STEL. The ACGIH recommends that short term exposures should exceed 3 times the TLV--TWA for no more than 30 minutes during the work day and under exceed five times the TLV provided the TLV--TWA is not exceeded. Thus this most widely used publication is directed towards the work place environment intensive exposure to a toxic gas. time The tJ.S. Government has two organizations involved in worker safety. Under the Department of Labor, OSHA has general responsibility for developing and enforcing regulations. Under the Department of Health and Human Services, the National Institute for Occupational Safety and Health (NIOSH) 82 p ---------- TRINITY CONSULTANTS, INC__________ * is 01126533 responsible for research to develop the technical basis for standards. These organisations jointly published a guide that *- defines acute levels of toxicity.3 It is entitled, "NIOSH/OSHA 9 Pocket Guide to Chemical Hazards". This is probably the most useful publication to establish safe one-time short-term exposure levels for assessing the hazard caused by a toxic gas cloud. One concept that is commonly used by toxicologists is ppm/min. For example, chlorine may have a value of 1000 meaning that a person can withstand 1000 ppm for one minute, 200 ppm for five minutes, or any other combination of values in which the product of concentration and time in minutes is 1000. It is improper to apply this technique to the TLV-TWA values without professional advice because the physiological effects of substances differ so widely. Two other publications provide a rich source of information to help establish tolerable levels of contaminants. N. Irving Sax is the author of "Dangerous Properties of Industrial Materials" `t "Patty's Industrial Hygiene and Toxicology"5is a publication consisting of five volumes. C. Air Contaminant Limits in Asibient Air Starting with Montreal in 1978 numerous governments in North America 83 TRINITY CONSULTANTS, INC. Tws of toxic compounds from industrial plants in the ambient air. According to a recent report, 14 states and 6 local programs have toxics regulatory programs in place.6 An even larger number have programs in preparation. Many states and localities use some form of ambient guideline or standard for the control of toxic air pollutants. Most of these use "factored" occupational values as a basis for ambient limit, at least for some pollutants A factored occupational value is the use of a constant fractional value to apply to all of a specific set of occupational limits to convert from a workplace guideline (based on exposure to a particular i contaminant over an eight-hour day, five days a week) to an ambient guideline. The occupational limits used most commonly for this purpose are the TLV--TWA, the OSHA limits and the NIOSH recommended criteria for occupational exposures in air. NIOSE recommendations are based primarily on medical science while OSHA considers technical feasibility and economic factors in its role as regulator. i Figure 16 is a summary of the limits adopted or proposed by selected state and local air pollution control programs D. Time Averaged Concentrations As was discussed in Chapter 111, the time average concentration 84 ----------- TRINITY CONSULTANTS, INC. VAD. 126535 Figure 16 SAFETY FACTORS USED TO DERIVE ACCEPTABLE AMBIENT CONCENTRATIONS FROM OCCUPATIONAL LIMITS State or Locality Safety Factor Applied to Occupational Limit Averaging Time Alabama Arkansas Connecticut1 Georgia1 Illinois # Indiana1 h Michigan Minnesota Mississippi Montana Nevada New Hampshire1 New Tork Rhode Island1 South Carolina Texas 2.5% (1/40) 1% (1/100) 0.5% (1/200)* 1% (1/100). or 2% (1/50)* depending on pollutant group 0.53% (1/300) if known human carcinogen, 1% (1/100) if not known human carcinogen 0.33% (1/300) for non carcinogens 1% (1/100) a 1% (1/100) for selected pollutants 1% (1/100) 3.3% (1/30), usually 2.4% (1/42) 10% (1/10) 1% (1/100) 0.33% (1/300), 2% (1/50) dependiug on toxicity category 1% (1/100) 0.24% (1/420) 1% (1/100), 0.1% (1/1000) 1 hour 24 hour 8 hour 24 hour 24 hour 24 hour 8 hour * 8 hour NA1 * 1 year* 8 hour NA1 1 year 24 hour NA1 30 minute 1 year (Continued) 85 VAB.0001126536 Figure 16 (cont*d) A S:it e cr Locality Safety Feetor Applied to Occupational Limit Averaging Time 0.24% (1/420) rpiria Tiseorsin* i California Philadelphia, Pennsylvania 1% (1/100) for carcino gens 1.7% (1/60) for noncarcinogens 2.4% (1/42) 2.4% (1/42), 2% (1/50), 0.33% (1/300) 1Q0% for selected pol lutants 0.24% (1/420) or 2.4% (1/42) 24 hour or 1 year depending on pol lutant 24 hour 24 liour NA* 1 year, 24 hour, 1 hour 8 hour 1 year :?entctive: program in preparation. s."'o: tvail&hle at the time of this writing. *--s reported in Radian Corporation, "Survey of State and Local Agency Programs :er C:t:r:l of Tonic Air Pollutants," Draft Report, Prepared for U.S. EPA, of Air Quality Planning and Standards, State and Territorial Air Pol.zzi:z Program Administators, and Association of Local Air Pollution Control June 8, 1983. 4 86 i e VAB.0001126537 is determined by counting the number of standard deviations of a 4 cloud that pass a certain point. If an observer is located close to a brief (few--second release )9 then an observer may only be breathing the toxic gas for a few seccnds. The rest of the air breathed over, say, five minutes will te fresh air. On the other hand if the observer is several kilometers away the peak instantaneous concentration would be nearly equal to the MTium 30-second average concentration. The science of establishing safe acute levels for 30-second, 1--minute or even 5aciaate periods is not well developed. Therefore, when analyzing possible accidents it may be best to analyze several averaging times. Most people spend most of their time indoors. There is a significant buffering effect in air movement into a building. Under ideal conditions the occupants cf a building could be warned and they would When the ventilation should be increased to the maximum extent possible to flush out any toxic gases that might have permeated the building. E. Method Used by EPA for Chronic Toxicity Studies. has the risk of citizens living near chemical plants. These studies are based on the use of the C2SM computer model and meteorological data collected at nearby S7 ---------- TRINITY CONSULTANTS, INC_________ ______ -va airports. There is some question regarding the effectiveness of this approach. First CDH is an urban model and any plants are located in rural areas. Nearby airport meteorclogical data may not be representative of conditions near the plant, particularly in mountainous areas. The CDH model does not consider the wake effects of individual structures, rather it adjusts the vertical dispersion coefficient if the release height is less than 50 meters. 88 TRINITY CONSULTANTS, INC. 4 CHAPTER VI: REFERENCES * 1. American Conference of Governmental Industrial Hygienists, "TLVs-Threshold Limit Values for Chemical Substances and Physical Agents in the Work Environment and Biological Exposure Indicies with Intended Changes for 1984-85". Available from ACGIH, 6500 Glenvay Avenue, Building 0-7, Cincinnati, Ohio 45211 (513)651-7881 $4.00. Office of Technology Assessment, Preventing Illness and he Workplace". April, 1985. (as quoted in Chemical and Engineering News, April 14, 1965 p.14.) 3. NIOSH/OSHA Pocket Guide to Chemical Hazards. Stock Number 017--033--00342--4, Superintendent of Documents, U.S. Govern ment Printing Office, Washington, DC 20402, pp. 191. $7.50. 4. N. Irving Sax, . ISBN Number 0-82^'-7250-4, ACGIH, Publications Section, 6500 Glenway Avenue, Building D-7, Cincinnati, OH 45211. 5. American Conference of Governmental Industrial Hygienists, Numbers 0-471-16046-5, 0-471-16042-3, 0-471-07943-X, 0-47109258--2, 0-471--02698-0. ACG1E, Publications Section, 6500 Glenway Avenue, Building D-7, Cincinnati, OH 45211. 6. U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Air Trxics Information Clearinghouse, Second ion on State and Local Agency Air Toxics Activities. March 1985. p.14. EPA No. 68-02-3889, WA15. Project Officer: Karen 1. Blanchard, 919/541-2350. 7. ibid, p.28 89 t TRINITY CONSULTANTS, INC. w 126540 71-- larr* Spills and Heavy Gases L review of the TLV-TWA list shows values ranging from less than 1 Some "inert as acetylene, helium and methane act as simple asphyxiants. No TLV is recommended but zze iuggestec minimum oxygen content is 18 percent by volume A Some zz rhese asphyxiants are explosive and care should be exercized to heep concentrations below the lower explosive limit. If oxygen is :g volume Cl 43,000 ppm). OSHA sets a limit of 19.5 percent oxygen in Til :c)o. (d)(9)(vi) and 16.5 percent oxygen in 29CRF1915 rotzmcn Dilute Clouds iic.ce the concentrations of primary concern for most gases is in :he range of less than 1 ppm up to 5000 ppm, this means that the :lcud contains no less than 99.5 percent air. As such, the co.ecular weight of the contaminant, or its original "scpferature, have virtually no effect on dispersion and can be ignored. More complex processes may exist near or at the source, but by the time the gas has been diluted to :oncentrations of interest, the cloud will be nearly all ambient ir. Moreover, the rate of dilution of the cloud will be primarily governed by the prevalent atmospheric turbulence. A TRINITY CONSULTANTS, INC T Whenever there is an accidental spill of a liquid or gas, some or all of the material volatizes. As the cloud of volatile siaterial and air moves gradually downwind, the natural process of atmospheric turbulence reduces the concentrations. If the a spill is of a hazardous material, the concentrations at some point downwind will fall below the toxic level. Regardless of the nature of the spill, atmospheric turbulence is generally the major factor in diluting the plume as it moves downwind. The initial turbulence of the actual release generally has only a minor effect on concentrations at distances beyond 250 meters or so from the spill. There are three types of spills: liquids, gases stored as liquids, and gases. In nearly all cases dense gas clouds are created. Buoyant clouds are created only when there is a small hole in a container of gas or when there is evaporation from a liquid pool on the ground. Buoyant plumes are also created when there is a fire. A more detailed description of the three types of spills follows: 1. Liquid spills. The spill of a material which is normally a liquid at 91 TRINITY CONSULTANTS, INC atmospheric pressure and temperature causes a pool to form* Examples of such liquids include benzene, acrylonitrile, and vinyl chloride* The liquid will evaporate from the pool at * a rate that can be calculated based on the vapor pressure of the liquid which governs transfer the area of the pool, the heat of evaporation, the air temperature, the ground temperature and the heat transfer of convection and radiation* The viscosity of the liquid will determine the rate of growth of the pool on flat ground. If the material is spilled into a ditch, both the surface exposed to the atmosphere and surface exposed to the warm earth w\ll be reduced, thus cutting the evaporation rate. In fact one suggestion for minimizing the emissions fro spills is to build concrete basins under the potentially leaking vessel. A small deep basin will result in minimum evaporation. By putting a sump in the basin, the spilled material can be quickly recovered. For most liquids the initial rate of emission will be greater per unit area than the equilibrium rate. As evaporation takes place, the pool will be cooled, reducing temperature evaporating Wu and Schroy have provided a good summary of the thermodynamics and heat transfer associated with liquid spills.2 A 92 TRINITY CONSULTANTS, INC. * If the spill of a liquid occurs on water, then the release rate of the material will be much greater than if tie spill * occurs on land* On land there is no circularict, only conduction, a much less efficient means of heat transfer. The rate of release of toxic material decreases as the temperature of the underlying surface decreases. If the patterns the water will help keep the pool relatively warm* The Chlorine Institute suggests that chlorine spilled on water should be assuated to vaporize3 Liquid Gas Spills* Many materials are stored in pressurized or refrigerated!, containers* These include ammonia, chlorine and liquified natural gas (LNG) and liquified petroleum gas (LPG', Tbs nature of the failure has much to do with how the release disperses. a. Small Hole in Vapor Space If the spill is a puncture in the top of the container where liquids do not escape, the material will etter the atmosphere as a gas. If the release rate is slcv and if 93 TRINITY CONSULTANTS, INC * 3^0^01126544 the gas has a molecular weight less than air. the buoyant If the mo weight is greater than air, the plume will rise due to momentun and then sink because of density differences. b. Large Hole in Vapor Space. If a large hole should suddenly exist in a tank containing liquified ammonia under pressure, the consequences are quite different than those associated with a small hole. If the hole is small, the escaping vapor can be replenished by evaporation from the liquid surface above which changes all. If the hole is large, the pressure above the surface is relieved instantaneously. Pressure at and below the liquid surface (which is the 6U3 Of atmospheric pressure and static head) than saturation vapor pressure. As a result, bulk toiling occurs and most of the contents of the vessel vill be ammonia he a will vaporize 20 percent of the vessel contents. remaining 80 percent becomes cloud of finely divided boiling liquid droplets at a temperature of -33C. Experiments confirm rapid depressurization occurs, the entire contents of A 94 TRINITY CONSULTANTS, INC 4 .0001126545 the container becomes airborne* c. Hole in Liquid Space* If the puncture or release occurs below the liquid level, then liquid vill enter the atmosphere* If the contents are stored at atmospheric pressure the liquid mill form a pool and as it evaporates gas vill enter the atmosphere* One conclusion that can be drawn from this observation is that it is safer to store liquified gases refrigerated at atmospheric pressure than in pressurized containers* If the contents are pressurized, then a portion of the liquid vill immediately flash to a gas while the liquid portion is rapidly cooled* d* Dense Gas Cloud* Because of the turbulence induced by the flashing of gas most tf the liquids do not form a pool on the ground but rather form an aerosal of liquid droplets* This cloud, cocpcsed of suspended boiling droplets, is called a "dense gas cloud"* A dense gas cloud is also formed when there is a catastrophic failure of an ammonia or chlorine tank. r j l f 1 j i 4 TRINITY CONSULTANTS, INC i 1126546 When all the boiling liquid droplets in a dense gas cloud vaporize, the cloud becomes neutrally buoya * the usual Gaussian dispersion equation apply and The location, dimensions and concentrations of gases in a dense cloud are analyzed using differential than the familiar Gaussian equations. A set of six partial differential equations has been proposed to analyze the characteristics of a dense gas cloud^including: A Equation Width Lateral Momentu Mass Conservation Mass Fraction Conservation Longitudinal Momentum Enthalpy Conservation Variables Horizontal velocity, gravity spread velocity and entrainment velocity. Hydrostatic force and surface drag. Entrainment velocities. Boil off from surface pool is added to local flux valves. Entrainment of ambient momentum (wind speed), acceleration from hydrostatic gradients, and surface drag. Surface heat transfer, entrainment of water vapor, ground ource of boiling cryogenic liquid and longitudinal dispersion. 96 TRINITY CONSULTANTS, INC. w VAB.0001126547 e. Descriptions of Releases In the case of a sodden release, such as a tank rupture, the dispersion process can be described as four phases according to Griffiths and Kaiser.6 First, there is the turbulence, called "flash off", caused by the rapid escape of the liquid or gas* For a 20-ton ammonia tank rupture, tests suggest that about 20 percent becones vapor while 80 percent remains as a liquid aerosol. A similar fraction of chlorine will flash at an ambient temperature of 85 F according to the Chlorine Institute* The liquid aerosol appears to observers as a cloud in fa the shape of a column or vertical cylinder* The gases within this cylinder are quite cold due to the evaporation of part of the gas. Second, this cylitier starts to slump, much in the way a column of water starts to spread out. During slumping, air is entrained fairly slowly and this stage will typically last 30 to 40 seconds for a 20-ton gas spill. Third, the cloud of liquid droplets now enters the ground-hugging phase in which the entrainment of air takes place at a rate less than that expected for a passively diffuse plume. The area of the top surface is 97 TRINITY CONSULTANTS, INC. much greater than the area of the sides and, therefore, most of the entrainment of air takes place through the top surface* Depending on the ambient temperature, the r gases in the cloud vill reach ambient air density in 3 to 5 minutes after slumping starts from a 20-ton spill* Fourth, the natural process of atmospheric turbulence takes over and the cloud diffuses like any other gas in the atmosphere. The boundaries between the phases are rather blurred and indistinct* The description of the four phases, however, is useful when discussing the atmospheric dispersion of dense gases. In the case of large volume releases, the dense cloud can remain intact for some distance* For example, the cloud of vapor formed from the release of 40 tons of ammonia at Pensacola, Florida, was tracked on a radar for an hour out to a distance of nine miles before it dissipated into a neutrally buoyant phase. On May 11, 1976, in Houston, an ammonia truck crashed from the elevated structure of the Southwest Freeway 1-610 interchange* The grass was "burned" in a circle A 93 TRINITY CONSULTANTS, INC with a radius of about 150 meters from the point of m impact and in the downwind distance out to a distance of about 1000 meters. The "burned" grass apparently reflects the initial slumping column followed by a ground-hugging dense gas cloud of liquid droplets that eventually warmed to become a gas. f. Shape and Characteristics of Dense Gas Clouds Slumping of a dense gas cloud takes place rapidly and it causes the cloud to spread out radially including * movement upwind until arrested by the wind. A raised front is formed with the slumped cloud assumming a doughnut-like shape and eventually decaying to pancake shape. The shape and movement of a dense gas cloud is nearly independent of atmospheric stability. A dense gas cloud moves more slowly than a buoyant cloud because of surface drag. Tests in the Burro series reported by Meroney show that with a wind speed of 2m/sec the center of the cloud moved at about a third the wind speed. The cloud dimensions for a 10 ton spill of LNG were approximately 200 meters wide and 6 meters deep at a location 140 meters downwind, 200 seconds after the release. 99 - TRINITY CONSULTANTS, INC. Griffiths and Kaiser repcrt that a 20 ton ammonia spill forms a cloud up to 4CI casters in diameter after 50 seconds and up to 600 meters in diameter after 100 seconds. Another characteristic of a dense gas cloud is that as the cylindrical cloud sltmps, concentrations occur upwind of the center of the release. In the case of Burro, they occurred up to 15 meters upwind. In Houston they extended about 150 meters upwind. The effects of gravity on a dense gas cloud are strong. In an effort to restrict the number and type of i variables that require consideration, the significant dense gas tests have been conducted on flat, open uniform terrain. These induce Porton Down, Maplin Sands, China Lake (Burrc) end the recent Thorney Island experiments. It is known qualitatively that cense gas clouds do not move uphill except with ruderaie strong winds and they may even roll down a hill against slight winds. Further research is necessary tc qualify the effects of topography.' 100 * TRINITY CONSULTANTS, INC__________ * * V V There has been extensive research conducted on dense gas spills mostly involving liquified petroleum gas. The studies generally are directed at determining the lover flammable limit (LFL) of a gas/air mixture. Depending on the gas, the LFL are in the range of 10,000 to 125i000 ppm, far in excess of a safe level for gases such as chlorine or ammonia. The dissipation of the dense gas cloud into a neutrally buoyant cloud and the dilution of the buoyant cloud down to levels of 100 to 500 ppm has not been studied. Various assumptions are made by scientists and a more accurate solution to this issue may cot occur for some time. g. Modeling Dense Gas Clouds. Although many scientists believe that adequate data exists to validate dense gas models, most are avaiting the availability of data from the China Lake and Thorney Island experiments for confirmation 1 i> At the point of transition to a neutrally buoyant cloud, the dense gas cloud may be up to several hundred meters vide but only a fev meters deep. 101 TRINITY CONSULTANTS, INC For highly toxic substances, for which the concentration of concern may be in the ppm range, the behavior during the gravity influenced phase of dispersion may not r significantly affect the calculations. Moreover, in most if not all cases, the Gaussian dispersion calculation will tend to overestimate concentrations relative to methods which combine a dense gas dispersion and Gaussian calculations. 3. Gas Spills. The spill of a material which is normally a gas both at atmospheric conditions and at storage and/or transporation conditions results in the formation of air/gas mixture at a temperature somewhat below ambient temperature. The reduced temperature is the result of the pressure reduction between storage and/or transportation conditions and atmospheric pressure. An analysis of such a release using hydrogen sulfide as an example is provided by Echols. 9 * 0. Bursts with Continuing Emissions When a tank or vessel fails, the release of the gas starts at a high rate but it rapidly decreases as the container becomes depressurized. A $ 102 TRINITY CONSULTANTS, INC- Under these conditions it is appropriate to divide the release into a series of individual bursts. The first the largest burst * should be analysed first. This provides a vorst case analysis. following burst contaminants survive the first puff, the person survive D. Lower Flammable Limits All combustible gases have a lower flammable limit. If the concentration is higher than this level, then any spark or flame can cause an explosion. As a result, good engineering practice l is to keep storage tanks of combustibles some distance away from open flames or sources of sparks. . 103 TRINITY CONSULTANTS, INC. CHAPTER VII: REFERENCES 1. ACGIH, TLV's, 1984-85, p.7. 2. Wu, John M. and Schroy, Jerry H. "Emissions from Spills" 1979* Paper presented at Conference sponsored by Air Pollution Control Association at Gainesville, Florida, February, 1979. (Proceedings available from Air Pollution Control Association, Pittsburgh, PA) 3. The Chlorine Institute, Inc. "Calculating the Area Affected by Chlorine Releases", June, 1982 (Chlorine Institute Pamphlet 74) 4. Kaiser , G.D. and Walker, B.C. "Releases of Anhydrous Ammonia fro Pressurized Containers - The Importance of Denser-Than-Air Mixtures" Atmospheric Environment 12:12 (December, 1978, P 2289-2300). 5. Meroney, Robert N. "Transient Characteristic of Dense Gas Dispersion" Journal of Hazardous Materials, 9 (1984, p.139-157). 6. Griffiths, R.F. and Kaiser, G.D. "The Accidental Release of Anhydrous Animonia to the Atmosphere - A Systematic Study of Factors Influencing Cloud Density and Dispersion" 1979. Draft document prepared for Safety and Reliability Directorate, United Kingdom Atomic Energy Authority, Cheshire. 7. Harris, N.C. "Heavy Gas Dispersion", Appendix 6 "The control of Major Hazards - Advisory Committee on Major Hazards - Third Report", 1984, Her Majesty's Stationery Office, London. 8. McQuaid, J. "Overview of Current State of Knowledge on Heavy Gas Dispersion and Outstanding Problems Issues", 1985, Presented at Heavy Gas (LNG/LPG) Workshop, Toronto. 9. Echols, W. Terry "Estimating the Hazardous Radius of Exposure From Accidental Releases of Hydrogen Sulfide Gas", Proceedings of 1976 National Conference on Control of Hazardous Material Spills, New Orleans. 104 TRINITY CONSULTANTS, INC VIII. Location of Spills and Data Required In all cases the most difficult part of analyzing a spill is to determine the quantity spilled. This task is particularly difficult in transportation accidents. P A. Transportation In most transportation accidents the person at the scene in rural areas is usually local firemen, a state policeman or a sheriff. In urban areas, many larger fire departments have a hazard material coordinator. The U.S. Department of Transportation publishes "Emergency Response Guidebook" (1984). Copies of this guide have been made available to each police, fire, civil defense and rescue squad vehicle in the United States. The procedure to use this guide is as follows: Identify the material from: a) Data on Shipping papers b) Four digit number on an orange panel c) Material name that may appear on vehicle Look up Material's 2-digit guide. Turn to numbered guide pages. 105 4 TRINITY CONSULTANTS, INC. The on-scene coordinator is encouraged to call CHEMTREC for * immediate advice for those at the scene of emergencies* CHEMTREC immediately contacts the shipper of the hazardous materials for more detailed assistance and appropriate follow-up* It is strongly suggested that the on-scene coordintor keep the phone line open* The CHEMTREC facility consists of a teleconferencing bridge which allows experts from the shipper or anyone else to communicate with the on-scene coordinator. The user of the Guide is advised to purchase U*S/ Geological r Survey Maps of the area of responsibility to aid in evacuations r where they are necessary* Preplanning and response team training is recommended* 9 Figure 17 is a reproduction of the Guide 20 which is used for chlorine, nitrogen dioxide, nitrogen tetroxide, and other gases* The guide also contains tables (Figure 18) specifying evacuation distances during the initial phase of an accident involving hazardous liquids or gases shipped in bulk or multiple-container loads If a hazardous material cloud goes between several multi--story T / Figure 17 HEALTH HAZARDS Poisonous; may be fatal if inhaled. Contact may cause burns to skin and eyes. Contact with liquid may cause frostbite. Runoff from fire control or dilution water may cause pollution. FIRE OR EXPLOSION May ignite other combustible materials (wood, paper, oil, etc.). Mixture with fuels may explode. Container may explode in heat of fire. Vapor explosion and poison hazard indoors, outdoors or in sewers. I1 j * -- tM ' v* * fNi ^^ f * 1 .. * Keep unnecessary people away; isolate hazard area and deny entry. Stay upwind; keep out of low areas. Ventilate closed spaces before entering them. Wear positive pressure breathing apparatus and full protective clothing. Evacuate area endangered by gas. (See Isolation and Evacuation Table in back of guidebook; find the material by name.) FOR EMERGENCY ASSISTANCE CALL CHEMTREC (800) 424-9300. If water pollution occurs, notify appropriate authorities. FIRE Small Fires: Dry chemical or C02. Large Fires: Water spray, fog or foam. Move container from fire area if you can do it without risk. Stay away from ends of tanks. Cool containers that are exposed to flames with water from the side until well after fire is out. For massive fire in cargo area, use unmanned hose holder or monitor nozzles; if this is impossible, withdraw from area and let fire burn. SPILL OR LEAK Keep combustibles (wood, paper, oil, etc.) away from spilled material. Stop leak if you can do it without risk. Use water spray to reduce vapor but do not put water on leak or spill area. Isolate area until gas has dispersed. FIRST AID Move victim to fresh air; call emergency medical care. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Remove and isolate contaminated clothing and shoes at the site. In case of contact with material, immediately flush skin or eyes with running water for at least 15 minutes. Keep victim quiet and maintain normal body temperature. Effects may be delayed; keep victim under observation. 107 TRINITY CONSULTANTS, INC. Figure 18 TABLE OP ISOLATION A EVACUATION DISTANCES INITIAL ISOLATION INITIAL EVACUATION NAME OF MATERIAL SPILLING OR LEAKING (ID No.) M. SPILL or LEAK FROM (drum, smeller container, or smell leek from tank) ISOLATE in all Directions feet LARGE SPILL PROM A TANK (or from many container*, drums, ate.) FIRST THEN EVACUATE IN A ISOLATE In all DOWNWIND DIRECTION Directions Width Length feet miles miles Acrolein (1092) 300 620 Acrylonitrile (1093) 90 Ammonia, anhydrous liquified (1005) Ammonia solution, with more than 44% (2073) Anhydrous ammonia (1005) 80 160 Boron trifluoride (1008) * Bromine (1744) 320 170 670 350 0A Carbon bisulfide (1131) Carbon disulfide (1131) * Chloride of phosphorus (1809) 50 110 100 220 Chlorine (1017) 140 290 Dimethy lamina, anhydrous. (1032) 80 Dimethyl sulfate (1595) 80 Epichlorohydrin (2023) 40 Ethylene imine (1185) 270 Ethylene oxide (1040) 80 Fluorine, cryogenic liquid (9192) 460 980 Hydrochloric acid, a* 9 anhydrous (1050) Hydrogen chloride, anhydrous (1050) Hydrogen chloride, liquid (refrigerated) (2186) 190 450 Hydrocyanic acid (1051) Hydrogen cyanide, anhydrous (1051) 90 Hydrofluoric acid, anhydrous (1052) Hydrogen fluoride, anhydrous (1052) 150 108 TRINITY CONSULTANTS* INC !i 01126559 Figure 18 (Cont'd) TABLE OF ISOLATION A EVACUATION DISTANCES NAME OF MATERIAL SPILLING OR LEAKING (ID No.) 1 1 INITIAL ISOLATION I INITIAL EVACUATION SPILL or LEAK FROM 1 LARGE SPILL FROM A TANK (drum, smaller container. 1 (or from many containers, drums, etc.' or small leak from tank) 1 FIRST THEN EVACUATE IN A 1 ISOLATE in all ISOLATE in all DOWNWIND DIRECTION Directions I Directions Width Length | feet 1 feet miles miles Hydrogen sulfide (1053) 4 + Methylamine, anhydrous (1061) 1 M oncm ethylami ne, anhydrous (1061) 4 4 i Methyl bromide (1062) 1 | 120 110 50 240 0.6 0.9 220 0.5 0.8 90 0.2 0.3 Methyl chloride (1063) 30 60 0.1 0.2 .Methyl mercaptan (1064) 370 770 1.9 3.0 i Methyl sulfate (1595) H Nitric acid, fuming (2032) Nitric acid, red fuming (2032) 80 100 170 1.4 2.2 210 0.5 0.7 Nitric oxide (1660) Nitric oxide and Nitrogen tetroxide mixture (1975) 90 180 0.4 0.6 Nitrogen dioxide (1067) Nitrogen peroxide (1067) Nitrogen tetroxide (1067) 110 220 0.5 0.8 Oieurr. (1631) Perchioromethyl1 mercaptan (1670) 280 220 580 1.5 2.2 450 1.1 1.6 Phosgene (1076) 600 1250 3.3 5.2 Phosphorus trichloride (1809) 110 220 0.5 0.6 Sulfur dioxide (1079) 120 250 0.6 0.9 Sulfuric acid, fuming (1831) Sulfuric anhydride (1829) Sulfur trioxide (1829) 280 580 1.5 2.2 Titanium tetrachloride (1838) 30 60 0.2 0.2 Trimethylamine, anhydrous (1083) 50 90 0.2 0.3 THIS INFORMATION IS FOE USE IN ADDITION TO THE GUIDE PAGE RECOMMENDATIONS OR HANDLING THE TOXIC HAZARDS OF THESE HATERIALS IF THEY ARB NOT ON PIRZ 109 TRINITY CONSULTANTS, INC. 'H buildings or down a valley, the cloud could affect people much further away than the distance specified* The guide also notes that occupants on the upper floors of multi-story buildings are likely to be safer remaining where they are if the heating and air-handling equipment in the building can be shut dovn. If a fire begins to burn the spilled material, the health hazard may become less important and the evacuation distance may not have to be as great as they were with no fire involvement. In order to estimate the dispersion of the gas at a spill, the following information is needed: Whether it is day or night Estimated wind speed Wind direction Amount of cloud cover (to determine stability) Description of topography 4 Some firms maintain libraries of USGS maps of the transportation corridors most commonly used in shipping dangerous materials* B* Accidents at Plant Sites The instrumentation at a plant often provides a good estimate of the amount of gas released. It is recommended that all plants which handle or process toxic gases record meteorological data and have that data available at several locations in the plant* This data should include the following parameters: no TRINITY CONSULTANTS, INC 126561 a) Wind speed b) Wind direction c) Standard deviation of wind direction A Wind direction should be recorded with a low-mass wind vane, not the type that looks like a wingless, single-engine airplane. The vane should respond quickly to variations in wind direction. Figure 19 illustrates a typical Weather Station. It is recommended that wind speed and direction be recorded at a 10 meter elevation. The approximate costs are as follows: Farameter(s) Cost Wind speed, wind direction, temperature and strip chart recorder Sigma-theta card Cassette recorder Tripod mast as shown $ 3200 600 2800 150 10 meter mast 300 1 Dew point sensor 673 i Solar panel (Solar radiation) 450 Tipping bucket rain guage 475 % The availability of real-time meteorological data will aid in forecasting the speed and direction of travel of any released material. Moreover, the recording of the data will be invaluable in determining the validity of any claims for compensation should there be an accident. ill TRINITY CONSULTANTS, INC. Figure 19 a 112 VAB.0001126563 Some firms that handle toxic gases place monitors along fence m lines* An analysis should be made of the width and the vertical dimension of any possible release* This should be compared to the actual or proposed spacing of inlets to the sampler* It is therefore suggested that the inlets to the sampler should be no more than 3 times sigma y apart in the horizontal direction and about one sigma z above grade for releases within 5 meters of the ground* i > iI l I < i I k i 113 TRINITY CONSULTANTS, INC * A 1. Limit the amount stored at the site* Design a manufacturing process that immediately consumes any toxic gases in further processing. The reduced risk of an accident must be weighed against the reliability of the manufacturing process in which, for example, the failure of a phosgene production unit results in the immediate shutdown of the toluene diisocyanate plant. 2. Construct a building around the plant or loading area. Many chemical plants are built outside with pipes and vessels suspended from a structural steel framework. If the entire process were located in a building, then a monitor could be installed on the forced draft building exhaust vent. Furthermore, the building exhaust vent could be elevated, like a stack, to greatly reduce ground level concentrations. In some types of facilities there is a fear of an explosion which militates against an enclosed structure One f inn enclosed the process area down to an area about six feet above grade. A large cooling tower fan was installed on the gabled roof. This arrangement overcame possible explosion problems while most 114 TRINITY CONSULTANTS, INC a* VAD.t-0e0r0m1:126565 a significant clevatier. 3. Conduct hazardous operations when dispersion is best. Bright, sunny days with coderate to strong winds are indicative of a great deal of atmospheric turbulence and the conditions which will most rapidly dilite a cloud. It may also be possible to select days or times wien the winds would not carry any cloud towards populated earners. If a railroad were to attempt to move a punctured tank car of hydrogen fluoride, it should be accomplished on a clear day vith strong winds in a direction to * affect the fewest people. A semi-conductor manufacturer should choose to move bottles : tczic gases such as arsine during the lunch hour when employees are absent or during the weekend day shift. 4. Properly train people. Then a disaster occurs, the reaction of most people is unpredictable. There have been cases where employees have run ttvarcs a chlorine cloud and successfully sued their employer. Tiereftre, it is prudent to develop a detailed plan and to reiearse it. Nearly everyone recalls tie fire drills that took place when they went to grammar sciocl. The fire bell would ring and students and teacher vcclc proceed quickly and orderly outdoors. After a veil* the fire drill became routine and because it is, deaths from school fires are virtually non-existent today A similar attitude is beneficial at a plant where drills should be conducted not just during the working day, but at all hours. Host of these drills can be announced in advance, but a few can be a surprise. \ L` The drill can test evacuation procedures, evacuation and plant shutdown procedures, evacuation and fire procedures. The drills can be only for plant personnel and on site contractors or they can be held jointly with local public safety officials. The ideal situation is one in which all personnel involved react out of habit as a result of regular drills. unique causes of the Bhopal misconnections One of the introduction instead of nitrogen into a storage tank. One can speculate that the threads on the fittings of the water and nitrogen lines were alike. By making these fittings unique, an error of this type can be avoided. Use existing equipment to increase dispersion. For example, if a vent that could carry a toxic gas release is near a boiler stack, duct the vent to it. The plume rise on the boiler stack will greatly reduce ground level concentrations. If there is an incinerator or burner, supply at least part of the burner 116 TRINITY CONSULTANTS, INC. UAB, air from the forced draft ventilation of a building in which hazardous gases are used* Provide communications equipment to nearby residents* In at least one location plant safety personnel can broadcast a message directly into homes that could be affected by a release* The residents can be directed to first, close all windows, second, open windows after the cloud has passed or, third, evacuate the area* Some plants are starting to rely on automatically dialed telephone messages* Although some plant managers have been reluctant to share their knowledge of the risks with nearby residents, this will be a requirement of British law effective January 1, 1986* use water sprays xests snow cast water spray mitigate the consequences of the release of heavy gases into the atmosphere*^ >2 The water spray curtain acts t quantities of air producing a rapid dilution of Several conclusions are drawn from the studies* dense plume. Location of the barrier makes little difference but by placing it closer to a source, both water use and construction costs are lowered* As wind speeds effectivenes of the barrier fell by 50 percent* Increasing the water pressure increased the rate of dilution. The water spray systems were most effective under stable 117 TRINITY CONSULTANTS, INC. conditions. In nearly all cases the resulting dilution was at least a factor of 10 and often could get as large as 50. The barriers most m rapidly decreasing flammable below the lower explosive limit. The use appears value where concentrations are less than 10,000ppm or distances are greater than 1000 meters from the source. 9. Construct retention areas. Construct dikes around storage tanks and build basins underneath large process vessels and rail or truck loading facilities. Design the basin to maximize the depth of the liquid and reduce the surface area. Make h 4 provision for pumping accumulated liquids to safe storage tank. 10. Ignite flammable gases. The standard procedure in natural gas drilling operations is to ignite a well blow-out if there is significant hydrogen sulfide in the gas. Not only does this convert the hydrogen sulfide to sulfur dioxide (a less hazardous gas) but it adds significantly to plume elevation because of plume buoyancy. 11. Store gases as refrigerated liquids. The catastrophic failure or even a large hole of a pressurized container results in an immediate release of the contents. If the same material were stored in a refrigerated container at atmospheric pressure, the A ! 118 TRINITY CONSULTANTS, INC leak from or failure of the container would result in a boiling pool on the ground. This would extend the period of release reducing the peak concentrations and allowing those in the path of the cloud more time to escape. If a method of containing the leak exists, then it may be possible to recover the product i reducing the magnitude of the release. 12. Use pressure relief valves. Many containers have "blow-out" plugs that melt or are forced out under excessive internal pressure. The use of pressure relief valves will reduce the quantity of the material released and distribute the release of the entire contents of a vessel over an extended period. 13. Sample for contaminants. One reason many accidents occur is because of contaminated raw materials. It is wise to sample all incoming raw materials as well aa manufactured raw materials to reduce the risk that contamination could cause an unplanned release. 14. Rely on a plan. Real-time systems for forecasting the path of a toxic cloud can be helpful. On the other hand, the use of these systems may reduce managements' interest in frequent, serious drills and thereby impart a false sense of security. Moreover, power to a computer may be lost if the accident is a result of a power failure or the catastrophic release itself causes a power failure. Management may wish to use the A 119 TRINITY CONSULTANTS, INC. K 1126570 periodic, unplanned power failures at its plants as a means evaluate shut-down procedures * computer-based aids. and emergency procedures using 15. Keep people indoors. The indoor concentrations of pollutants are generally less than those outdoors. 3 concentrations is: The ratio of the two Xi 1-e-ct Xo Xi Indoor concentration Xo Outdoor concentration Air changes per unit time t Time interval building will experience between 0.1 and air change per hour depending on the make air to the ventilation system changes hour. In a typical office building with^ 1,5/ changes per hour the indoor five minute concentration wiLl be only (,,1-e-1.5/12 ) or 12 percent of the outdoor concentration. A I \ * 120 TRINITY CONSULTANTS, INC YAD.9001126571 CHAPTER IX: . REFERENCES Hw 1. Mcronty, R. N. and Neff, D. E. "Numerical Modeling of Water Spray Barriers for Dispersing Dense Gases", Boundary Layer Meteorology, 31 (1985) 233-247. 2* McQuaid, J. and Fitzpatrick, R. D., "Air Entrainment by Water Sprays: Strategies for Application to the Dispersion of Gas Flumes", Journal of Occupational Accidents, 5 (1983) 121-133* 3. Beattie, J R, "A Quantitative Study of Factors Tending to Reduce the Hazards from Airborne Clouds", Appendix 3 Canvey Report (1978). 121 TRINITY CONSULTANTS. INC. 4 X. Computer Models The first eleven models employ puff algorithms anc may also use continuous release algorithms. The next group of nodsIs starting with X. PTPLU are continuous release models that are part of the UNAMAP series of programs. A. SPILLS This model was developed by Shell Development Company, Houston, Texas, and given to the U.S. Government for public distribution. 1 Three options depending on the nature the spill have been incorporated in the model: 1) continuous spills, such as leaks from tank cars, tanks or pipelines, 2) instantaneously-formed pools of liquids or liquefied gases and 3) stacks, where the emission rate is assumed to be known. This model does not analyze concentrations from dense gas clcuds. For options 1 and 2, thermophysical properties (available as a subroutine in the hazardous are used to calculate, through heat and mass transfer mechanisms, the evaporation rate, which becomes the emission rate for the atmospheric dispersion calculations. A 122 TRINITY CONSULTANTS, INC m MM The first option is for a small continuous leak of a liquid Two kev variables are unknown rea of the pool and the emission rate into the atmosphere. Since the area of the pool is difficult to determine, the model makes the simplifying assumption that the emission rate from the leak is equal to the emission rate to the atmosphere. The model calculates the spill area based on convective mass transfer (evaporation). The model also assumes that the liquid spilled is at ambient temperature and pressure so that there is no heat transfer between the pool and the earth. The second option considers instantaneously formed pools. The mechanism by which the evaporation will take place depends on the nature of the chemical spilled. Chemicals with a normal boiling point below ambient temperature will first flash off due * to the pressure drop between the storage pressure (the storage temperature has to be specified by the user) and atmospheric pressure. The evaporation rate due to this adiabatic flash calculation is assumed to occur during the first minute after the spill. The chemical will then form, a pool of liquefied gas at its normal boiling point. In reality the remaining liquid after rapid depressurization is often an aerosol rather than a i boiling pool. The difference between the temperature of the boiling pool and the ambient temperature will cause heat to be transferred from the ground (the soil is assumed to be at 123 TRINITY CONSULTANTS* INC. ambient temperature) to the pool by conduction, and from the atmosphere to the pool by convection. Mass transfer, due to the wind bloving over the pool, takes over when the heat transfer evaporation rate becomes equal to the mass transfer evaporation rate. Note that this occurs because the heat transfer rate decreases as time increases whereas, the mass transfer rate is independent of time. The emission rate is set to zero when all the chemical is evaporated. With this option the user must specify, both the amount spilled and the area of the pool. The third option provides for dispersion of gases from stacks, vents, leaks or other point sources. The user supplies up to 100 emission rates for each time interval from the initiation of the phenomenon. If only one rate is supplied, the program considers the case to be steady state. This option incorporates the Briggs plume rise formulas. This Pasquil1-Gifford dispersion coefficients are used in this model. Total calculated concentrations at a receptor are determined by integrating the contributions from puff centers within four standard deviations from the receptor. For area sources the initial plume width is set equal to the area width divided by 4.3. The output of the program contains a printer-plot of the A 124 TRINITY CONSULTANTS, INC AD .-6001126575 * isopleths of concentrations from a release. Typically * the TLV-TWA and the STEL are displayed for the 36 chemicals analyzed by the program. This program designed for use on an IBM mainframe must have some type of communications link to the host computer. SAFER This system is the most widely used real-time toxic gas response system today. It is a sophisticated product that has been marketed very effectively. There are over 30 installations including some overseas. The manufacturer is SAFER Emergency Systems, Inc., 756 Lakefield Road, Westlake Village, GA 91361. The system is designed around a 32-bit microprocessor employing a Motorola 68000 CPU. It includes a high-resolution 19-inch color graphics screen, a monochrome CRT and a printer. Meteorological information is recorded on site and directly entered into the system. Monitored information on chemicals can also be entered directly. In its usual operating mode the programs are activated by a light pen. The color graphics terminal typically displays 125 ---------- TRINITY CONSULTANTS, INC. diagrams of the plant so the operator can pinpoint a leak and maps of the area around the plant on vhich the projected path of a gas cloud is displayed. The monochrome screen provides instructions to the operator such as persons to be notified and their telephone numbers. The printer is useful to print out the meteorological record for the landmarks, phone numbers, time of distance the plant and the proper mes Also reported is the type of chemical maximum downwind distance the cloud will travel and a table of critical concentrations at various downwind distances. The system can automatically messages over the telephone lines, and keep track of which calls were made and which calls were completed. The system answers critical questions often asked by plant officials during a release of a hazardous chemical. These include: 1) which direction the vapor cloud is moving, 2) will the concentrations downwind of the plant site exceed critical toxicity levels or explosive limits, 3) how soon will the cloud arrive at population center, 4) when will the cloud disperse to a safe level. 126 TRINITY CONSULTANTS, INC. -------- -VAB In the case of a leak, sensors tied directly into the system automatically detect the ambient, concentrations of the escaping vapor8 and sound an alarm at the central station, thus alerting the plant operator to the release* The plant operator then enters information into the system regarding type of chemical released and size of leakage ("default" amounts are pre-stored for each plant equipment)* Wind direction, speed, temperature and stability data, measured from a tower and sensors located on the plant site, are continuously fed into the system and automatically updated* The system then quickly calculates the projected path of the vapor cloud and atmospheric dispersion rate of a specific chemical* This calculation of the cloud is displayed in different colors and superimposed over base maps of the plant and surrounding community. Should the wind direction change, the system will automatically shift the projection of the cloud to the new direction* Properties of the plant's chemicals are already pre-programmed into the system so that density, dilution and evaporation effects are taken into account in the on-going calculations* Print-outs of the emergency actions to be taken are tailored to the severity of the situation, thus eliminating the problem of 1 i 127 TRINITY CONSULTANTS, INC. T over-reacting and causing an unnecessary evacuation. However, should the release be a severe one, the print-out provides pre-planned instructions on whom to call and what to say This includes telephone number, areas affected, evacuation routes, emergency procedures and health effects from exposure to the vapors. The persion model is a multiple Lagrangian Wall and can wind r both puffs and continuous sources. Complex terrain and channeling can be incorporated. No information was provided on the dispersion coefficients or on the mechanics for determining liquid evaporation or buoyancy effects. The basic price of common use of SAFER conducting drills. system The in postulating scenarios and in C. CHARM This model was developed by Radian Corporation, 8501 Mo-Pac Boulevard, Austin, TX 78766, CHARM is an acronym for Complex Hazardous Air Release Model and it has been implemented on an IBIfr*PC with a color graphics screen, Bata on 57 compounds are stored. Algorithms for continuous liquid release, continuous 128 TRINITY CONSULTANTS, INC YA&: included. instantaneous liquid or gas releases and are n The dispersion model has been validated against actual jjD tudies of gas release experiments and can simulate the trwwport and dispersion of buoyant* neutral or heavier-than * releases* Meteorological data can be input automatically event data and archived for documentation and data analysis The software is about $10*000 and there are about 40 purchases* Hot all purchasers have been able implement CHARM J)yvdtiaMj D CARE q) This system was developed by Environmental Systems Corporation 200 Knoxville* TN CARE is an for Computerized Airborne Release Evaluation System The software can be implemented on an IBM-PC or HF200 personal computer The system consists of 5 modules The source module contains an inventory of chemicals and their properties* It includes a gravitational slumping model for use with dense The meteorological module relies on observed data or it modifies 1 4 i 129 TRINITY CONSULTANTS, INC 1126580 in complex terrain. The dispersion module is based on a puff-advection model that has a variable trajectory. The display shows the location and concentration of the hazardous chemical. An effects module provides information on the hazard posed to health and welfare by the materials in the plume. It includes dose calculations for nuclear releases as well as data on the TLV and IDLH for chemicals. The fifth module provides the user with recommended response actions. E. HASTE This system was developed by Environmental Research and Technology, Inc., 696 Virginia Road, Concord, HA 01742. HASTE i is an acronym for Hazard Assessment System for Toxic Emissions. The system can be implemented on an IBM-PC or on an NEC APC. There is one known installation. The system sell for about $40,000. f The system features include a menu driven decision assistance program supported by color graphics, computerized inventories of hazardous chemicals and their properties, pre-programmed release scenarios, dispersion models for dense gas and neutrally buoyant 130 TRINITY CONSULTANTS, INC YA&OT01126581 plume*, real-time or user-input meteorological data, archiving p capability for input data and results and automated emerging protocols* F. EPCHEMS II This system was developed by Enviroplan, 59 Main Street, West Orange, HJ EPCHEMS II consists of Enviroplan Chemical Emergency Mitigation Systei and a Continuous Emissions Monitoring Data Acquisition System* The system bases its source term on the continuous monitoring or pressure, flov and level for any number of storage tanks and pipes to determine whether parameters are in accepted safe ranges* It alerts control room personnel and aids personnel to respond to the emergency. It calculates and displays concentrations from the release on maps of the area* The system is implemented on a small Data General minicomputer* G* MESOCHEM, JR* This system was developed by Impell Corporation (a subsiding of Combustion Engineering, Inc.) 350 Lennon Lane, Walnut Creek, GA 94598. 131 TRINITY CONSULTANTS, INC_________ :--------- B This system was originally developed on a main frame computer for clients in the nuclear industry. It uses color graphics and has any if not all the features common to SAFER, HASTE, CARE and EPCHEHS II. H. Other Systems Both NUS (Gaithersburg, HD) and Dames & Hoore (Chicago, IL) have been prominent in developing systems for emergency response in the nuclear industry on large main frame computers. Both firms offer similar systems to chemical firms for toxic gas releases. Two other systems under development include CEES, Energy Impact Associates, Pittsburgh, PA and HARRS, Ensco, Indian Harbor, FL. I. EPA Puff * In 1982, EPA published "Estimating Concentrations Downwind from an Instantaneous Puff Release". A copy of this publication is included in the Appendix. This model is based on a summary of experiments on the dispersion of clouds from quasi-instantaneous releases contained in Heteorology and Atomic Energy.3 Turner refers to this work in the Workbook of Atmospheric Dispersion * Estimates. 4Although it is difficult to make direct comparisons between the puff model and continuous models, the concentrations calculated using the quasi-instantaneous dispersion coefficients 132 ------------- TRINITY CONSULTANTS, INC. VT^KDOO1126583 are several times those using Pasquill-Gifford coefficients* The EPA program calculates peak instantaneous values and * time-averaged values for times selected by the user* It assumes steady state wind conditions* The user supplies the initial height of the release, and the standard deviations of the initial cloud size. The three stability categories analyzed are unstable, neutral and stable. Concentrations are calculated for 12 downwind distances ranging from 10 meter8 to 30 kilometers* This model is not particularly user-friendly in terms of both the calculations required by the user before creating an input and in the input format* The model does represent EPA's thinking regarding the analysis of quasi-instantaneous spills* TRPUF This model is based on the EPA puff model and was developed by Trinity Consultants, Inc* Its input is much more user-friendly and the output is significantly more useful than EPA puff. The model is executable on an IBH-PC and includes a graphics capability in which plots are produced on the PC printer* Figure 20 summarizes the differences between TRPUF and the EPA puff model* Figure 21 is a copy of the output of TRPUF and Figure 22 is a plot of the output produced on an IBH-PC printer. This model is used primarily to help management analyze various 133 TRINITY CONSULTANTS, INC. ------- -------------- VAB.Q A 20 Major Differences Betveen TRPUF and EFA Puff Models EPA Model Concentration at release point and farther downwind Calculares a virtual distance so that the calculated concentra tion at release point is equal to the concen tration used as input. The user can also specify the distance downwind for which cloud dimensions are known. Vectorially adds initial sigma values to sigma values for downwind distances. Concentrations Calculates peak instantaneous as well as average concentra tions f;r all recep tors. Calculates peak instantaneous at all receptors and average concentrations only at discrete receptors. Receptors Receptc r grid consists of 70 c :vrwind distances 59lected easily :y the user. Receptor grid consists of 12 downwind dis tances from 10 meters to 30 kilometers downwind Plume Rise Uses Briggs' unstable/ neutral momentum plume rise fer all stability classes. User inputs a fixed value independent of wind speed, Concentration Units User mg/nr scerlec-gts/n?pm grams/m3 Other Information Display; travel time and si values TRINITY CONSULTANTS, INC. ------------------- =----- ---126585 f Figure 21 fRFUF - nans COPYRIGHT 1985 TRINITY CONSULTANTS, INC* A PUFF MODEL DEVELOPED BY TRINITY CONSULTANTS, RICHARDSON, TEXAS 9 EXAMPLE OF TRPUF3 214/234-8567 RELEASE AMOUNT (POUNDS) 2.20500 RECEPTOR HEIGHT ABOVE GRADE (FEET) MOLECULAR HEIGHT = 64.00 EXIT VELOCITY (FEET PER SECOND) AIENT TEMPERATURE (DEG F) * 88.00 STACK DIAMETER (FEET) AMBIENT PRESSURE (MB) >1013.00 HIND SPEED (MPH) STACK HEIGHT (FEET) CONFUTED VIRTUAL DISTANCES (FT) HORIZONTAL VERTICAL UNSTABLE 3.3 3.3 NEUTRAL 16.4 16.4 STABLE 8S.3 8S.3 5# INITIAL CONCENTRATION (P:`M) * 5.00E+05 5*000 INITIAL HORIZONTAL SI6HA (FEET) .00 1*50 INITIAL VERTICAL SIGHA (FT) * .00 5*0 DOUNUISD DISTANCE (FT) - 0. 60.00 DOUNNIND PEAK INSTANTANEOUS CONCENTRATIONS AVERAGE CONCENTRATIONS FOR 300. SECONDS -- SIGMAS (FEET) ----- DISTANCE UIG/M3) (UG/H3) TRAVEL UNSTABLE NEUTRAL STABLE (FEET) UNSTABLE NEUTRAL STABLE HAXINUH UNSTABLE NEUTRAL STABLE MAXIMUM (MINUTES) HOH VER HOR VER HOR VER 20 5.5409E-07 2.2128E-09 6.7703E-09 5.5409E-07 1.7391E-09 4.5425E-12 1.1093E-U U7591E-09 .045 40 2.0281E+01 7.2767E-10 4.4680E-09 2.0281E+01 1.1391E-01 2.2348E-12 8.5457E-12 1.I391E-01 .091 3C w 7 11 2 3 1 1 * 3422 60 1.9562E+03 3.3662E-10 3.1362E-09 1.9562EF03 1.5583E+01 1.366K-12 6.8435E-12 1.5583E+01 .136 7 15 4 4 2 SO 1.2150E404 1.8649E-10 2.3043E-09 1.2150E+04 1,246IE+02 9.3783E-13 5.6399E-12 1.2461E+02 .182 9 18 4 5 2 2 100 2 3975E+04 M553E-10 1.7539E-09 2.8975E+04 3.6224E+02 6.9102E-13 4.7519E-12 3.6224E+02 .227 11 22 5 6 2 *> 4. 120 4.50773E+04 4.24A9E-10 1.3728E-09 4.5077E+04 6.6321E+02 2.9391E-12 4.0747E-12 6.6321E+02 .273 13 25 6 7 3 A L, 140 5.6339E+04 1.9488E-07 1.0993E-09 5.6339E+04 9.5187E+02 1.5296E-09 3.5444E-12 9.5187E+02 .318 15 27 7 7 3 *9i 160 6.2312E+04 1.7899E-05 8.9711E-10 6.2312E+04 1.1873E+03 1.5694E-07 3.1199E-12 1.1873E403 .364 17 30 8 8 3 * + 180 6.4114E+04 5.3571E-04 7.4386E-10 6.4114E+04 1.3586E+03 5.1847E-06 2.7738E-12 1.3586E+03 .409 19 33 8 9 3 P 200 6.3107E+04 7.4087E-03 6.2525E-10 6.3107E+04 1.4710E+03 7.8394E-05 2.4873E-12 1.4710E+03 .455 20 35 9 9 c 220 6.0408E+04 5.9064E-02 5.3177E-10 60408E+04 1.5350E+03 6.7793E-04 2.2469E-12 1.5350E+03 .500 22 38 10 10 * % 240 5.6808E+04 3.1416E-01 4.5695E-10 5.6808E+04 1*562IE+03 3.8856E-03 2.0429E-12 1.5621E+03 .545 24 40 11 10 4 1 260 52823E+04 1.2322E+00 3.9622E-10 5.2823E+04 1.5620E+03 1.6331E-02 1.8680E-12 1.5620E+03 230 4.3773S+04 3.8245E+00 3.4633E-10 4.8773E+04 1.5427E+03 5.4052E-02 1.7168E-12 1*54271+03 .591 .636 26 43 23 45 12 11 12 12 4 4 4 4 > 4 300 4,4843E+04 9.8854E+00 3.0491E-10 4.4843E+04 1.5103E+03 1*4S36E-01 1.5848E-12 1.5103E+03 .682 30 47 13 12 5 j 44134E+04 2.2095E+01 2*7017E-10 4*l!34E+04 1*4692E+03 3.5084E-01 1*4690E-12 1.4692E+03 .727 50 14 13 5 W 3.7693E+04 4.3934E+01 2*4079E-10 37693E+04 1*4228E+C3 7*3567E-01 1.3666E-12 14228E+03 .772 vw 52 15 13 K V * 360 *mrV :v* 3.45;6E+04 3.1659E+04 7.9416E+01 1.3271E+02 2*1575E-10 1*9424E-10 3*4536Er04 3.1659E+04 1*3733E+03 l*3225E+03 l*39c3E+00 2.4503E+00 1.2756E-12 t*1942E-12 l*3733E+03 13225E+03 -Oj 2,?050tr04 2.O776E+02 1*7566E-10 29050E+04 l*2717E+03 4.0143E+00 M2I2E-12 1.2717E+03 .818 .864 .909 * * 54 564 -+ 5872 vW 15 14 16 14 17 15 s w 5 6 * * 26688E+04 3.0788E+02 1 * 5949E-10 2.6688E+04 l*2215E+03 6.2112E+00 1.0553E-12 1.2215E+-C3 24554E+04 4*3556E+02 1.4536E-10 2*4554+04 1 *1726E+03 9*1568E+0C 9.9557E-13 1.1726E+03 2.2625E+04 2 *0882E+04 5.9227E+02 7,/844E+02 1.3294E-10 12l?3E-10 2.2625E+04 2*0882E+04 1.1252E+03 1*07973+03 1.2952E+01 176c0E+01 9*4130E-13 8.9179E-13 1*12523+03 1.0797E+03 1.9305E+04 99350E+02 1.1225E-10 1.9305E+04 1*03613+03 2*3400E+01 8.4643E-13 1.03613+03 ,955 1.000 1.045 1.091 1.136 604 ' 4m 18 15 6 42 62 18 16 6 * 44 65 19 16 . 45 67 20 17 6 i* 47 69 21 17 7 520 1.78773+04 1.2360E+03 1.0359E-10 1.7877E+04 9.9452E+02 3.0148E+01 S.0487E-13 9.9452E+02 540 1.6533E+04 1.5038E+03 9.5846E-11 1.6583E+04 9.5490E+02 3.7935E+01 7.6657E-13 9.5490E+02 560 1.54083+04 1.7940E+03 8.8899E-U 1.5408E+04 9.1724tt02 4.6751E+01 7.3121E-13 9.1724E+02 530 1.4339E+04 2.1035E+03 8.2645E-11 1.4339E+04 8.8147E+02 5.6565E+01 6.9849E-13 8.8147E+02 600 1.3366E+04 2.4290E+03 7.69973-11 1.3366E+04 8*4753+02 6.7328E+01 6*68133-13 8.4753E+02 1.182 1.227 1*273 1.318 1.364 49 71 21 17 7 i 51 72 22 18 7 . 52 74 23 18 7 *t * J 76 24 19 7 * 56 78 24 19 8 620 1.2478E+04 2.7668E+03 7.1881E-11 1.2478E+04 B.1534E+02 7.8978E+01 6.3992E-13 8.1534E402 640 1.1667E+04 3.1135E+03 6.7234E-11 1.1667E+04 7.8480E+02 9.1440E+01 6.1363E-13 7.8480E+02 660 1*09243+04 3.4656E+03 6.3002E-11 1.0924E+04 7.55B5E+02 1.0463E+02 5.8910E-13 7.5585E+02 63C 1.0244E+04 3.8200E+03 5.9138E-11 1.0244E+04 7.2B38E+02 1.1847E+02 5.6616E-13 7,28333+02 700 9.6184E+03 4.1736E+03 5.5602E-11 9.6184E+03 7.C232E+02 1.3285E+02 5.4467E-13 7.02323+02 1.40? 1,455 1.500 1.545 1*591 57 80 25 20 8 * 59 82 26 20 8 t 61 84 26 21 8 * 62 86 27 21 8 t V 64 87 28 21 9 c V 135 VAB.0001126586 Figure 21 (Cont'd) A TRPyF - MDBS COPYRIGHT 1985 TRINITY CONSULTANTS, INC. A PUFF HODEL DEVELOPED BY TRINITY CONSULTANTS, RICHARDSON, TEXAS * EXAMPLE 0* TRPUF5 214/234-8567 AMOUNT (POUNDS) * 2.20500 RECEPTOR HEIGHT ABOVE GRADE (FEET; MOLECULAR WEIGHT = 64.00 AMBIENT TEMPERATURE (DEG F) = 83.00 EXIT VELOCITY (FEET PER SECOND) STACK tIAMEIER (FEET) AMBIENT PRESSURE <HB> =1013.00 COMPUTED VIRTUAL DISTANCES (FT) HORIZONTAL VERTICAL WIND SPEED (M?H) STACK HEIGHT (FEET) UNSTABLE 3.3 3.3 NEUTRAL TABLE 16.4 85.3 16.4 85.3 5. INITIAL CONCENTRATION (PPM) = 5.OOE+C5 5.000 INITIAL HORIZONTAL SIGMA (FEET) > .00 1.50 INITIAL VERTICAL SIGMA (FT) = .00 5.0 DOWNWIND DISTANCE (FT) = 0. 60.00 DOWNWIND PEAK INSTANTANEOUS CONCENTRATIONS DISTANCE (UG/M3) (FEET) UNSTABLE NEUTRAL STABLE MAXIMUM AVERAGE CONCENTRATIONS FOR 300. SECONDS -- SIGMAS (FEET) ----- (UG/M3) TRAVEL UNSTABLE NEUTRAL STABLE UNSTABLE NEUTRAL STABLE MAXIMUM (MINUTES) HOR VER HOR VER HOR VER 800 900 1000 1100 1200 71553E+03 5.4742E+03 4.2882E+03 3.4273E+03 2.7867E+03 5.8462E+03 7.215SE+03 8.2037E+03 8.3252E+03 9.1378E+03 4.1752E-11 3.2330E-11 2.5660E-11 2.0786E-11 1.7128E-11 7.1553E+03 7.2158E+03 8.2O37E+03 8.8252E+03 9.1378E+03 5.9044E+02 5.032It+02 4.3417E+02 3.7870E+02 3.3350E+02 2.C986E+02 2.S307E+02 3.6025E+02 4.2249E+02 4.7338E+02 4.5504E-13 3.8755E-13 3.3524E-13 2.9373E-13 2.6012E-13 5.9044E+02 5.0321E+02 4.3417E+02 4.2249E+02 4.7338E+02 1300 1400 2.2997E+03 1.922SE+03 9.2101E+03 91056E+03 2.2435E-11 3.2298E-10 9.2101E+03 9.1056E+03 2.9620: 2.6504 +02 +02 5.1310E+02 5.4262E+02 36422E-13 5.5729E-12 5.1310E+02 5.4262E+02 *VV V * iOvO 1700 1.6255E+03 '1.3832E+03 1.1962E+03 S.8774E+03 8.5673E+03 8.2069El03 4.2657E-09 4.0331S-08 2.8633E-07 8.8774Et03 8.5673E+03 8.2069Ef03 2.3874 2.1634 1.970? +02 +02 +02 5.6329E+02 5.7S51E+02 5.S361E+02 7.SC31E-11 7.7955E-10 5.8267E-09 5.6329E+02 5.765IE+02 5.8361E+02 *: fWtr*ItAI 1 wVv 1900 A 0^v *\ V 'J 2300 ^4 ;^imm m* wV 1.0390E+03 9.0896E+02 8.0039E+02 4.5860E+02 7.3191E+03 7.4205E+03 7.0225E+03 5.2344E+03 1.6029E-O6 7.3509E-06 2.8491E-05 4.1562E-03 7.8191E+03 7.4205E+03 7.0225E+C3 5.23*4E+03 1.8041E+02 1.6587E+02 1.5310E+02 1.0768E+02 CVJi* 3578E+C2 3401E+02 J 7917E+02 5. 2927E+02 3.4233E--08 1.64 2SE -07 6.65 fIE -07 1.1757E -04 5.8576E+02 5.3401E+02 5.7917E+02 5.47a/ 2.8996E+02 3.9020E+03 9.5734E-02 3.9O20E+C3 3.C300E+0* 4 614E+02 3.16 ?5E -03 4.6614E+C2 2500 1.9643E+02 2.9559E+03 7.9806E-01 2.9558*-03 4. C661E+02 3.02 HE--02 4,06611+02 * a r *s -- .V 4Zp V V " 1 .V VV - - A Aj JV V 1.4003E+02 1.0382E+02 7.9402E+01 &*i^31:+01 22832ET03 1.7977E+03 1.44Q6E+03 1.1727E+03 3.6077E+00 1.1O04E+O1 2.5727E+01 4.9876E+0I 2.2832E+03 1.7977Etv3 1.4406E+03 1.1727S+03 5.0613E+01 4.1762:^01 3.5087E+01 2.9S?:i+01 3. 5-495E+02 cAto * 1133E+02 "478E+02 n * -412S+02 w=1*k .51iC3W I5E -01 -01 1.32 2 * 8C 3'r8toE.+rO0O0 3.5495E+02 7 tlTTrir"*- W t * to WW to > W to 2.747SE+02 2.4412E+02 A VV v v - V* V V v-3 m. ft *; +VVV) 3000 4.9885E+01 4.0665E+01 3.3651E+01 2.8210E+01 2.3913E+01 9.6808E+02 8.09I7E+02 6.3386E+02 5.8368E+02 5.C261E+02 B.4380E+01 1.2893E+02 1.8222E+02 2.4233E+02 3.0710E+02 96808:f02 3.0917E+02 6.83S6E+02 5.8368E+C2 5.0261E+Q2 2.5747 +01 2*?371 +01 1fr?37L 1.72421+01 1.5266 +01 2. 1327E+02 1. 9635E+02 1. 7762E+02 1. :151E+02 1. 4756E+02 33E+00 16E+0C -A1 1i * 7/ wUw1 * # W to : V i :7t+01 2.3? 65E+01 2.1827E+C2 1.9635E+02 1.7762E+C2 1.6151E+C2 1.4756E+02 1.818 2.045 2.273 2.500 2.727 2.955 3.182 3.409 3.636 3.864 4.091 4.318 4.545 5.632 6.81S 7.9*, 9.091 10.227 11.364 4 CrtA 13.636 14.773 15.909 17.045 18.182 72 96 81 105 89 113 97 122 105 129 32 23 10 35 25 11 39 27 11 42 29 12 45 31 13 5 5 6 6 6 113 137 121 145 129 152 137 160 145 167 49 33 14 52 34 15 56 36 16 59 38 17 62 39 18 7 7 7 7 8 152 174 66 41 19 W0 160 181 69 43 20 3 4lU*wA 188 72 44 21 8 206 * 2ne2-1n 89 105 51 58 25 29 10 11 281 283 12! 65 33 12 317 311 136 71 3? 1 ft 1J 7305A4 WJV *1tow 339 376Q67 wjw 152 167 183 77 83 89 41 45 4? 14 iJ 461 419 198 95 53 16 496 C7i wW A 444 462 213 100 228 105 57 61 17 IS 566 493 243 111 65 18 600 516 259 116 68 19 S300 ^000 I1W^ 0ft0ft * V JVV < * * * AV- AV A?VF 2.0482E+01 4 *3625E+02 3 * 7435E+02 4.3625E+02 1.3582E+01 1. 3541E+02 3.08 16E+01 1.3541E+02 1.7694E+01 3.3138E+02 4.4211E+02 4.4211E+02 1.21373+01 1. 2475E+02 3.8274E+01 1.2475E+02 1.3510E+01 1.1923E+01 1.0582E+01 2.9706E+02 2.643BE+02 2.3647E+02 5.7276E+02 6.3328E+02 6.8952E+02 5.7276E+02 6.3328E+02 6.8952EF02 9.8079E+00 30 .8f5t42?E+0*0A vV - fa' 1. \ f V1 ; Vi 9. ?^54E+0l 01 -57r:+01 5.44 14E+01 A 0 *>c ti c 11E+01 7* li ;7E+0l 1.0700E+02 9.9554E+01 9.2S79E+01 19,318 20,455 22.727 23.864 25,000 635 540 272 121 72 20 669 563 287 126 76 21 737 608 316 135 83 v> 77: 630 331 140 87 23 805 652 345 145 91 23 < - Aft .vv AA ^A to V v V 123 00 * * ft ^ A + W v Jv 4 ^* **.rA*:fti * Vv 9.4439E+00 '3.4680E+00 7.6266E+00 6.8971E+00 6.260?:+00 2.1247E+02 1.9172E+02 1.7368E+02 1.5790E+02 1.4404E+02 7.4102E+02 7.8752E+02 8.2893E+02 8.6532E+02 8.9682E+02 7.4102E+02 7.B752E+02 8.2893E+02 8.6532E+02 8.9682E+G2 7.3110E+00 6.6695 rift." ml V V 6.1012E+00 5.5960E+00 . #F r i ic f *1 41 * vInc- * V V 8. 6365E+01 8. 1422E+01 C473E+01 7 > 1957E+01 6 7S20E+01 7.9645E+01 8.6865E+0! 3.7S 7E+01 8.7887E+01 9.59CSE+01 9.590SE+01 1.0365E+02 1.0365E+C2 D7E+024 4 - to + J. *i 1.110"+C2 26.136 27.273 23.40? 29.545 30.682 838 673 872 694 905 715 938 736 971 757 360 149 94 374 154 98 3:8 158 102 402 163 105 417 167 109 24 25 25 26 26 136 VAB.0001126587 MAXIMUM CONCENTRATIONS (UG/M3) FOR ALL STABILITIES 01 1.00E+00 1.00E+01 1.00E+02 1.00E+03 1.00E+04 Figure 22 EXAMPLE OF TRPUF5 loO + 137 VAB.0001126588 This model is used primarily to help management analyze various leak scenarios and determine the likely risks* K. PTPLU PTPLU is an adapted and improved version of PTMAX for quickly * analyzing the approximate location of maximum concentrations and the meteorological conditions under which it occurs for a single point source* Most air quality studies will start by analyzing a representative sample of stacks with this program to guide the receptor placement in more extensive modeling* PTPLU determines maximum through a process of iteration* In this process, concentrations are calculated for gradually increasing downwind distances until the peak is peak is program decreases the downwind distance until maximum found* Stack tip downvash and partial plume rise can be considered in the calculations* A requires the user to specify the meteorology* In addition to analyzing point sources, it accepts area sources, two types line sources and two types of curved path sources* Up to 99 138 TRINITY CONSULTANTS, INC. *T VAB.0001126589 each type can be ana Concentration estimates can be made at 99 user-specified One unique feature is a superior area source algorithm. This makes models particularly useful in analysing, fugitive dust sources emissions from waste treatment ponds and land fills. transportation sources, and situations involving sources other than stacks. K. ISCST This model is the most versatile of the EPA model for analyzing short term concentrations because of its numerous features that aid the user. If used unwisely, it can be very expensive in terms of computer time. Sources may be grouped so that average concentrations or deposition from combined sources can be calculated. The 1SCST model can analyze point, area and volume sources. Source emission rates may be varied. Receptors may be located in Cartesian or polar coordinates. The effects of stack-tip downwash, building wakes and gravitational settling may also be modeled. ISCST has one rural and two urban modes. The Rural Mode uses rural mixing heights and Pasquil 1-Gifford dispersion 139 TRINITY CONSULTANTS, INC. coefficients. Urban Mo de uses urban mixing heights. Pasquil1-Gifford coefficients, and redefines the and stability classes as D (neutral) stability. Urban Mode also uses urban mixing heights and Pasquil1-Gifford coefficients. ions comb ine s the and stability classes, and uses the Pasquil1-Gifford dispersion coefficients for the stability class one step more unstable than the indicated category For example, if the meteorological data Urban Mode 2 will use the coefficients for B stability. Urban Mode 2 is recommended for sources but should not used for stack sources modeling studies regulatory purposes. pollutant decay chanism exponential time-dependent the user can specify a decay coefficient. Particulate matter with an appreciable gravitational settling velocity can modeled gravitational option. The user divides particulate emissions into maximum of 20 settling categories according particle size. The settling velocity. emissions and surface reflection coefficients must be specified for each category. A 140 TRINITY CONSULTANTS, INC r VAB.0001126591 Emission rates may be varies, 1) by hour of the day, 2) by season or month, 3) by hour of the day and season or 4) by wind w speed and stability class. For point sources the following parameters must be specified: release height, exit velocity, inside diameter and exit temperature. The effect of nearby building wakes on concentrations can be modeled using the Huber-Snyder method by entering the building height, width and length. Entering these dimensions automatically causes the wake effects option to be used. * For area sources, the user enters the location of the southwest corner of each area source square, the length of a side and the effective emission height. For volume sources, the user enters the location and the height of the center of the volume source and the initial horizontal and vertical plume dimensions. The building wake effects option cannot be used with volume or area sources The user may select either a Cartesian or polar coordinate system to locate receptors. UTM coordinates can be entered if a CtrttBim system is specified. For the polar system a radial distance from a user designated origin and the angle measured clockwise from north are specified. For a single source or a 141 TRINITY CONSULTANTS, INC. 4 VAB.OQ * group of sources in close proximity, the polar system is easiest to use. For widely separated sources, the Cartesian system is usually more convenient. The user may elect to enter a receptor P grid and/or discrete receptors. A Cartesian or polar grid can be generated by the program. Discrete receptors may be located in either Cartesian or polar coordinates. The coordinate system used to specify discrete receptors does not have to be the same as the grid system. The user may find it convenient, for example, to use Cartesian l coordinates to locate discrete receptors along a plant fence line and polar coordinates for locating a receptor grid beyond the fence line in the same run. If the source or sources being modeled are located in gently rolling terrain, the user may input terrain elevations for the base of each source and for each receptor. Receptor heights cannot exceed the lowest stack height or effective emission height. There are six categories of program output. Any or all of these categories may be output at the user's option. The first category reproduces the input data for the problem run. This category contains all control parameters, meteorological and other constants, receptor data and source data. Additionally, A f aXX hourly Mtcorolojictl proccs86d by the piro^^ttn nsy b6 output ti ptrt of this CAtegory The second c&tegory produces an output containing the concentrations at each receptor for each day of meteorological data processed in the problem run. For each day, tables shoving concentrations for time periods and groups of sources specified by the user are printed. The third category produces an output containing the concentrations at each receptor for groups of sources specified by the user tveraged over the number of days of meteorological data processed in the run. This option allovs average concentrations for time periods up to a year to be calculated with ISCST. The fourth category contains tables of the highest and second highest concentrations calculated at each receptor, for sources or groups of sources time periods specified by the user. The fifth category contains a table of the maximum 50 concentrations calculated for the problem run for each time period and source group combination. The sixth category outputs the concentrations to magnetic tape. If deposition is being calculated, deposition values can be output using the above options. N. VALLEY This model has two modes of use. It can be used to estimate 24-hour and annual concentrations at receptors located above 143 TRINITY CONSULTANTS, INC. VAB.OQftl 126594 mm COMPLEX COMPLEX this. Alternatively, VALLEY can be used to calculate annual averages in flat terrain for rural areas. The model analyzes 112 receptors located at seven distances on sixteen radial lines. The user can also specify worst-case short-term meteorology for use in complex terrain. Ground-level elevations are subtracted from the effective stack height. In no case, however, is the effective stack height allowed to be less than ten meters. This is illustrated in Figure 23. Short-term calculated concentrations from area and/or point sources are calculated using Briggs1 plume rise and Pasquil1-Gifford vertical dispersion coefficients. In the horizontal, the plume is assumed to be 22.5 degrees wide. The model assumes that a given type of meteorology will persist for 6 hours out of 24. term estimate. The output consists of a print-plot of calculated concentrations along with detailed data. The user can specify a print-plot of each source total from all sources and an map the option permits one to scale the map so that it can be placed directly over standard U.S. Geological Survey maps. This model has been criticized widely, but EPA continues to use until a better model is proven. One of the frequent A t 144 TRINITY CONSULTANTS, INC. TERRAIN ADJUSTMENTS FQR SELECTED GAUSSIAN MODELS VALLEY MODEL STABLE CONDITIONS- e uV0) XM E t- M h O UJ UJ iD X 3 Q. < z -I s 2 oJ O 2 2 3 -I 1 I if -I II < oX UJ X UJ o<9 tc VAB.0001126596 questions concerns the 10-meter assumption, but it is relatively unimportant at distances of 2 kilometers or more from a stack. p More important is the shape of the terrain. If a plume is carried towards a vertical cliff then plume inpingement may occur. On the other hand, if the terrain were rather gently sloping, the air would tend to follow the slope. One study indicated that the overestimate in this case was a factor of 20. TEM8 The TEM (Texas the Texas Air Control Board to predict air pollution concentrations for periods up to 24 hours ha8 been revised and modified to increase its flexibility and utility. The current TEM The TEM was developed as an 1 tentative to the EFA models. PTMPT In developing the TEH the Texas Air Control Board incorporated a number of enhancements that provided flexibility and speed in the program operation. PTMPT and PAL were originally developed to provide a method to compare calculated and observed pollutant concentrations. For this comparison, the user input receptor points and meteorological data that would correspond to actual conditions. In contrast, the TEM calculates concentrations for a program generated grid using meteorological data supplied by the user. 146 TRINITY CONSULTANTS, INC. By varying the input of meteorological data, the TEM is used primarily to identify worst case conditions over the area covered by the grid. Both PTMFT and PAL could also be used to simulate worst case conditions, but these conditions could only be analyzed for user-specified receptor points. An additional enhancement made to TEM reduces the program run time. This enhancement creates a data table of precalculated constants. This data table allows the program to go through the concentration calculations only once and interpolate the other values. This enhancement provides accurate concentration predictions with a substantial saving of computer time. In 1983, TEM was modified to allow the user to input building dimensions so that wake effects can be analyzed as they are in ISCST. Finally, the TEM uses a time-averaging technique to spread the plume in the crosswind direction. The program takes the calculated sigma--y values for a 10-minute period and adjusts it 30-minute. 1-hour method the mass of the plume cross section is conserved for all averaging times. The hour concentration may be obtained by summing the three-hour values for eight scenarios or 24 1-hour 147 TRINITY CONSULTANTS, INC. ADJUSTED SIGMA-Y RELATED TO SAMPLING TIME Stability (P-G) 10 Minutes 3Q Minutes 1 Hour 3 Hour A B C D E &F 1.0 2.10 3.35 7.04 1.0 1.83 2.68 4.90 1.0 1.60 2.14 3.42 1.0 1.40 1.71 2.38 1.0 1.21 1.37 1.66 Sampling time options 1 through 4 correspond 10-, 30- and 180--minute times Sampling time 60- hour evaluations using either eight 3-hour scenarios or twenty-four 1-hour scenarios. The last two options are for a variable evaluation time depending on the number of scenarios entered. Option 7 assumes the scenarios are while option 8 assumes one hour. For example, using option 7 with six 10-minute scenarios will produce a 1-hour average. TEH calculates concentrations at up to 2500 locations rectangular grid from up to 300 point sources (stacks) and 50 area sources. The user has a list of receptors with concentrations, a concentrations m their correct relative location, a punched card output of concentrations for subsequent use in plotting. list of the amount pollutant contributed important to each receptor and a concentrations for each scenario. 148 TRINITY CONSULTANTS, INC TO01126599 CHAPTER X: REFERENCES 1* Fleischer, H.T. "SPILLS An Evaporation/Air Dispersion Model for Chemical Spills on Land", December I960. User's Guide available from National Technical Information Service (NTIS), publication number PB83-109470 ($403). 2. Petersen, William B. "Estimating Concentrations Downwind from an Instantaneous Puff Release", August 1982. Available from U.S. Environmental Protection Agency as EPA 600/3-82078 or from NTIS as PB82-261959. 3* Slade, David H. "Meteorology and Atomic Energy", 1968. U.S. Atomic Energy Commission, pp 120, 173-175. 4. Turner, p. 41. 149 TRINITY CONSULTANTS, INC XI. Evaluation of Risks "Safe" does not mean risk-free. There is no activity or product 4 that does not carry some potential for accidental injury. Often this is related to the misuse of a product or equipment. Vhat "safe" mean8 is that society considers the risk acceptable. This chapter is concerned with how to identify possible hazardous situations, some typical causes of hazards, how to conduct a hazard and operability survey and briefly how to relate the hazard to risk. A. Development of Accident Scenarios Before applying the techniques for analyzing dispersion in the atmosphere, an analysis should be performed to define the possible disaster scenarios. From such an analysis the plant manager can distinguish the accidents which have trivial consequences from those that are significant. Furthermore, the significant possible accidents can be dissected to determine whether improved process design, modification of equipment, improved operator training or other safety measures could be employed to reduce the risk. This analysis of significant disaster scenarios will aid in the preparation of contingency plans for the plant. Although the computer provides plant managers with the ability to respond in real-time, it would be unwise to not rehearse responses for the A 150 TRINITY CONSULTANTS, INC. 01126601 most likely disaster scenarios The loss of life from releases or ignition of flammable materials in this century is about equal to the loss of life from hazardous gas releases. Host studies of hazards generally include both ignitable releases as veil as toxic gas releases. The property dasiage from explosions and fires is often much greater than from a toxic gas release alone. The table below summarizes accident statistics. Substance Reference Chlorine Chlorine Ammonia Flammable gases Ammonium Nitrate Ethylene Oxide 1 2 1 * 1 1 1 Accidents Total Fatal 18 10 28 15 11 5 24 19 33 22 Deaths in Fatal Accidents 112* 120* 41 306+ 1132 5 * Excludes deaths of about 5000 allied troups at Ypres, Belgium in April, 1915. + Excludes the LPG incident in Mexico City, 1984 in which 300 lives were lost. Reference 1 is dated 1979 while Reference 2 is dated 1974. There have been other releases of toxic gases and compounds: Year Location Substance 1928 Late 70*s 1976 Early 80*s 1984 Hamburg, Germany Lake Charles, LA Seveso, Italy Palo Alto, GA Bhopal, India Pho 8gene Phosgene 2,3,7,8 TCDD Arsine Methyl diisocyante Deaths 10 1 none 1 1600 151 TRINITY CONSULTANTS, INC B. Causes of Failures On June 1, 1974 a release of 40 tons of cyclohexane vas ignited in a large fire ball which largely destroyed a chemical plant at Flixborough, England, killing 28 workers. Several public inquiries were held and one result was a decision to conduct an extensive study of the chemical refinery complex at Canvey near the mouth of the Thames. This study was the first major risk assessment study made for a large refinery/chemical complex. The British Health and Safety Executive Commissioned a $600,000 study which was conducted by the Safety and Reliability Directorate of the Atomic Energy Authority. The selection of the contractor was a recognition of the fact that the nuclear industry has pioneered the development of risk analysis procedures. The principal factors involved in failures include:5 a. Operator errors b. Metallurgical fatigue or aging of materials c. Internal or external corrosion d. Loss of process control, e.q. pressure temperature, flow, etc. e. Overfilling f. Introduction of Impurities g. Fire and/or explosion h. Missiles i. Flooding Risk is usually stated in terms of the probability of an event in a year. Thus, an event that can occur once in 100 years has A 152 TRINITY CONSULTANTS* INC. a probability of 10E-2 tbit year* One event in a million years is 10E-6 A surprising number of accidents are the result of operator error in which water is introduced to a tank inadvertently* an improper chemical is used to clean a tank or an operator h. incorrectly pumps caustic soda into a tank of sulfuric acid* It is not enough to examine the obvious sources of a toxic gas release* it is also important to speculate on the reactions of a- chemicals manufactured, stored or consumed at a site* C* Hazard and Operability (HAZOP) Studies One of the first steps to assess potential hazards is a carefully structured hazard and operability (HAZOP) study. It is suggested that a team of three to five members be assembled along with flow sheets of a proposed or an existing process.6 The team should meet for no more than three hours chairman As a general rule* each individual part studied, such as each main pipeline into a vessel* will take about 15 minutes. Another way to estimate time is to allow 2*5 hours per vessel* The author of the Guide indicates that after several sessicns the initial tedium vanishes and the members start to derive satisfaction from such a thorough analysis of a design* The purpose of the study is to define the hazards* In some cases solutions for the hazards can readily be identified but in * other cases special studies may be necessary to develop solutions. D* Risk Analysis It is generally desirable to distinguish between individual risk and societal risk* "Individual Risk" is defined as the risk to an individual of an event* "Societal Risk" is the risk to society of an event in terms of number of fatalities* Thus, individual risk varies from place to place depending on where the person happens to be at the time of a major accident* The societal risk is a measure of a combination of the likelihood and severity of a single event* Risk is a quantified by three factors: a* Accident frequency or probability b* Accident severity c* Exposure - the measure of the opportunity to be involved with an accident* 1. Analyzing Risk Once hazards are identified it becomes relatively simple to assess probabilities* Consider, for example, a plant with 200 meters of piping* The risk of failure of pipe is 3*10E~7 per meter per year*7 Thus, the likelihood of failure for the network is A 154 TRINITY CONSULTANTS, INC 200 * 3 * 10E-7 6 * 10E-5 per year Assume that valves exist to limit the quantity released but there is 1 in 100 chance that they will fail to work. The total risk of a large failure is: 6 * 10E-5 * 10E-2 - 6 * 10E-7 There is also a risk of release of smaller quantities of gas betveen the values of 0.99 * 6 * 10E-5 - 6 * 10E-5 If the gas is flammable, the risk of release can be 4 multiplied by the probability that ignition will occur before the released gases are diluted belov the lover favorable lisdLt. Finally, meteorological and population "+ location data is used to assess the probability of a gas release affecting nearby residents. Statistical data is available to assess the probability of many other events. Some of the probabilities used in the second Canvey report include: Rupture of refinery process vessels from all modes 4.4 * 10E--5 per year Railroad tank car derailment and puncture 10E-8 per km Probability of fire after LPG car puncture 0.73 per event Aircraft crash into process area of a refinery 5 * 10E--6 per year The Canvey report provides an extensive risk analysis of 155 TRINITY CONSULTANTS, INC ship loading and unloading accidents. The final result of this work was a series of tables that by the second report had assessed the average individual risk at 35 * 10E-6 per year for residents living near the Canvey complex* There was also a one in a thousand risk that ten or more lives would be lost in an incident each year* By way of reference the individual risk of death from motor vehicle accidents in Great Britain is 130 * 10E-6 and all other accidents about 190 * 10E-6 2* Computer Model Needless to say, it is expensive time prepare a detailed plan for a plant or for a large complex. A London-based consultant, Technica, Ltd., completed a traditional study in 1981 for selected areas near Rotterdam for the Rijnmond Authority. They then developed a user-friendly computer program for risk analysis of process plants called "SAFETI".8 The code sells for about $70,000, but it is available from timesharing vendors. The user will typically be trained for about a week and spend an added one or two days collecting data for each process unit such as a group of storage vessels, chlorine plant cell room, or cracking furnace section. A ! fH IP 156 TRINITY CONSULTANTS, INC A plant data file it created by an interactive program which prompts the analyst in a logical sequence* Other data * needed includes the distribution of population by location, the distribution of ignition sources and meteorological data* * The output consists of individual risk contour plots which are overlaid on a map of the area and so called F-H plots* The frequency of an event (F) is plotted against the number of fatalities (N) for societal risk in a log-log presentation* Value of Risk Analysis There are many uncertainties involved in any HAZOP and risk analysis survey* First, it is difficult to speculate on all the possible operator errors that could occur* Even if a reasonable method of assessing risk is completed, there is still a great deal of uncertainty as to the consequences given the rather inaccurate nature of dispersion modeling, the number of people that will be affected, the response of individuals to acutely toxic doses and whether the people affected will be outdoors or in buildings with varying ventilation rates* Perhaps the best that can be accomplished is to use risk assessment to evaluate relative risks* The iteration of 157 TRINITY CONSULTANTS, INC. 4 Chapter XI: References 1* Health and Safety Commis a ion "Advisory Committee on Major Hazards -- Second Report" (1979) Her Majesty's Stationery Office, London p. 10-16* 2. Simmons, John A., Erdmann, Robert C. and Haft, Barry Y* "Risk Assessment of Large Spills of Toxic Materials", 1974 Hazardous Materials Conference p. 166-175* 3* Health and Safety Executive, "CANVEY: An Investigation of Potential Hazards from Operations in the Canvey Island/Thurrock area*" (1978) Her Majesty's Stationery Office, London* 4* Health and Safety Executive, "CAHVEY: A Second Report* A Reviev of Potential Hazards from Operations in the Canvey Ieland/Thurrock Area Three Years After Publication of the Canvey Report" (1981) Her Majesty's Stationery Office, London* * 46. Chemical Industry Safety & Health Council of the Chemical Industrie Association Limited, "A Guide to Hazard and Operability Studies" (1 hemical Industries Association (CIA), 93 Albert Esibankment* London Second CAHVEY Report (1981) p. 70* Technica, Ltd*, "SAFETI -- Report on A Computer Based System Assessment of a Chemical Plant Using a Simplified Classical (1984). London. i- Jd<3< 4S& M6&dtr 159 TRINITY CONSULTANTS, INC. A. Implementation Schedule for S.I. 1984/1902, "The Control of Industrial Kaj:r Accident Hazards Regulations". B. Tabulation of Pascuill-Gifford dispersion coefficients for various downwind distance. C. Petersen, William 3., "Estimating Concentrations Downwind from an Instantaneous Puff Release", (August 1982) U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 (EPA 600/S-C2-078 or PB 82-261959). D. Wei, E. T., "Report for Trinity Consultants (on Arsine)", July 21, 1984, Personal Communication. F E. "World Bank and ITC Guidelines for Indentifying. Analyzing and Controlling Majcr Hazard Installations in Developing Counties" (Draft-February 1S55) World Bank, Washington, DC. A TRINITY CONSULTANTS, INC. VAH .0001126611 Table 1 Timetable lo r compliance - manufacturers X o K> < a i s 5? i _] | T| *1 _S_ ** w X IA * i A V ,, 3 I* a i|2 1 * f8l* 1 lllli! ISs* iliii u* IIS* I } c*5|3!lil 2 | Is III ? ,c!st|S1S;I I* * II FIGURE A MANUFACTURER'S GUIDE TO THE CIMAH REGULATIONS RURAL VERTICAL DISPERSION COEFFICIENTS (METERS) DOWNWIND DIST (KM) 0. 010 0. 020 0. 030 0. 040 0. 050 0. 060 0. 070 0. 080 0. 090 0. 100 0. 110 0. 120 0. 130 0. 140 0. 150 0. 160 0. 170 0. 180 0. 190 0. 200 0. 210 0. 220 0. 230 0. 240 0. 250 0. 260 0. 270 0. 280 0. 290 0. 300 0. 310 0. 320 0. 330 0. 340 0. 350 0. 360 0. 370 0. 380 0. 390 0. 400 0. 410 0. 420 0. 430 0. 440 0. 450 0. 460 0. 470 0. 480 0. 490 0. 500 ------------------------------ AB 1. 58 1. 24 3. 05 2. 37 4. 47 3. 45 5. 87 4. 51 7. 25 5. 56 8. 61 6. 59 9. 96 7. 61 11. 30 8. 61 12. 63 9. 61 13. 95 10. 60 15. 43 11. 59 16. 91 12. 57 18. 40 13. 54 19. 89 14. 51 21. 40 15. 47 22. 96 16. 43 24. 53 17. 39 26. 11 18. 34 27. 70 19. 29 29. 30 20. 23 30. 96 21. 23 32. 62 22. 22 34. 30 23. 21 35. 98 24. 21 37. 67 25. 20 39. 59 26. 19 41. 52 27. 18 43. 48 28. 17 45. 45 29. 16 47. 44 30. 14 49. 69. 31. 13 51. 96 32. 12 54. 26 33. 11 56. 60 34. 09 58. 96 35. 08 61.34 36. 06 63. 76 37. 05 66. 20 38. 03 68. 67 39. 02 71. 16 40. 00 74. 27 41. 10 77. 42 42. 20 80. 64 43. 30 83. 91 44. 41 87. 23 45. 52 90. 61 46. 63 94. 04 47. 74 97. 52 48. 86 101. 06 49. 97 104. 65 51. 09 STABILITY CD 0. 91 0. 63 1. 71 1. 15 2. 47 1. 63 3. 22 2. 10 3. 95 2. 55 4. 66 2. 98 5. 37 3. 41 6. 07 3. 83 6. 76 4. 24 7. 44 4. 65 8. 12 5. 05 8. 79 5. 45 9. 46 5. 84 10. 12 6. 23 10. 78 6. 62 11. 44 7. 00 12, 09 7. 38 12. 74 7. 76 13. 39 8. 13 14. 03 8. 50 14. 67 8. 87 15. 31 9. 23 15. 94 16. 57 9. 60 4 9. 96 17. 21 10. 32 17. 83 10. 68 18. 46 11. 03 19. 08 11. 39 19. 71 11. 74 20. 33 12. 09 20. 95 12. 42 21. 56 12. 74 22. 18 13. 06 22. 79 13. 38 23. 41 13. 70 24. 02 14. 02 24. 63 14. 33 25. 23 14. 65 25. 84 14. 96 26. 45 15. 27 27. 05 15. 58 27. 65 15. 89 28. 25 16. 19 28. 85 16. 50 29. 45 16. 80 30. 05 17. 10 30. 65 17. 40 31. 24 17. 70 31. 84 18. 00 32. 43 18. 30 E 0. 51 0. 92 1. 29 1. 64 1. 98 2. 31 2. 62 2. 93 3. 24 3. 53 3. 82 4. 10 4. 38 4. 66 4. 93 5. 20 5. 46 5. 72 5. 98 6. 24 6. 49 6. 75 7. 00 7. 24 7. 49 7. 74 7. 98 8. 22 8. 46 8. 70 8. 92 9. 13 9. 35 9. 56 9. 77 9. 98 10. 19 10. 40 10. 61 10. 81 11. 02 11. 22 11. 42 11. 62 11. 82 12. 02 12. 22 12. 41 12. 61 12. 80 F 0. 36 0. 63 0. 87 1. 10 1. 32 1. 53 1. 74 1. 94 2. 13 2. 33 2. 51 2. 70 2. 88 3. 06 3. 24 3. 41 3. 58 3. 76 3. 93 4. 09 4. 25 4. 41 4. 57 4. 72 4. 88 5. 03 5. 18 5. 33 5. 48 5. 62 5. 77 5. 92 6. 06 6. 20 6. 35 6. 49 6. 63 6. 77 6. 91 7. 05 7. 19 7. 32 7. 46 7. 59 7. 73 7. 86 8. 00 8. 13 8. 26 8. 40 H.l VAB.0001126613 RURAL VERTICAL DISPERSION COEFFICIENTS (METERS) DOWNWIND DIST (KM> 0. 510 0. 520 0. 530 0. 540 0. 550 0. 560 0. 570 O. 580 O. 590 0. 600 0. 610 0. 620 0. 630 0. 640 0. 650 O. 660 0. 670 0. 680 O. 690 0. 700 0. 710 0. 720 0. 730 0. 740 0. 750 O. 760 0. 770 O. 780 0. 790 O. 800 O. 810 0. 820 0. 830 0. 840 O. 850 0. 860 O. 870 0. 880 O. 890 O. 900 0. 910 0. 920 O. 930 O. 940 0. 950 O. 960 O. 970 O. 980 0. 990 1. 000 A 109. 13 113. 71 118. 39 123. 17 128. 05 133. 02 138. 10 143. 28 148. 56 153. 94 159. 42 165. 00 170. 69 176. 47 182. 36 188. 35 194. 44 200. 63 206. 93 213. 33 219. 83 226. 43 233.14 239. 95 246. 87 253. 89 261. 01 263* 24 275. 57 283. 00 290. 54 298. 19 305. 94 313. 79 321. 75 329. 82 337. 99 346. 26 354. 64 363. 13 371. 72 380. 42 389. 23 398. 14 407. 16 416. 28 425. 51 434. 85 444. 30 453. 85 STABILITY BC0 52. 22 33. 03 18. 59 53. 34 33. 62 18. 89 54. 47 34. 21 19. 18 55. 59 34. 80 19. 47 56. 72 35. 39 19. 77 57. 86 35. 98 20. 06 58. 99 36. 56 20. 35 60. 13 37. 15 20. 64 61. 27 37. 73 20. 92 62. 41 38. 32 21. 21 63. 55 38. 90 21. 50 64. 69 39. 49 21.78 65. 84 40. 07 22. 07 66. 99 40. 65 22. 35 68. 13 41. 23 22. 63 69. 29 41. 81 22. 92 70. 44 42. 39 23. 20 71. 59 42. 97 23. 48 72. 75 43. 54 23. 76 73. 91 44. 12 24. 03 75. 06 44. 70 24. 31 76. 23 45. 27 24. 59 77. 39 45. 85 24. 87 78. 55 46. 42 25. 14 79. 72 80. 88 47. 00 47. 57 25. 42 Cnc AOOf 82. 05 48. 14 25. 97 83. 22 48. 71 26. 24 84. 39 49. 28 26. 51 85. 57 49. 85 26. 78 86. 74 50. 42 27. 05 87. 92 50. 99 27. 32 89. 09 51. 56 27. 59 90. 27 52. 13 27. 86 91. 45 52. 70 28. 13 92. 63 53. 26 28. 40 93. 81 53. 83 28. 67 95. 00 54. 39 28. 93 96. 18 54. 96 29. 20 97. 37 55. 52 29. 47 98. 56 56. 09 29. 73 99. 75 56. 65 30. 00 100. 94 57. 21 30. 26 102. 13 57. 78 30. 52 103. 32 58. 34 30. 79 104. 51 58. 90 31. 05 105. 71 59. 46 31. 31 106. 90 60. 02 31. 57 108. 10 60. 58 31. 83 109. 30 61. 14 32. 09 E 12. 99 13. 19 13. 38 13. 57 13. 76 13. 95 14. 14 14. 32 14. 51 14. 69 14. 88 15. 06 15. 25 15. 43 15. 61 15. 79 15. 97 16. 15 16. 33 16. 51 16. 69 16. 87 17. 05 17. 22 17. 40 17. 57 17. 75 17. 92 18. 10 18. 27 18. 44 18. 61 18. 78 18. 96 19. 13 19. 30 19. 47 19. 63 19. 80 19. 97 20. 14 20. 31 20. 47 20. 64 20. 80 20. 97 21. 14 21. 30 21. 46 21. 63 F 8. 53 8. 66 8. 79 8. 92 9. 05 9. 18 9. 30 9. 43 9. 56 9. 69 9. 81 9. 94 10. 06 10. 19 10. 31 10. 44 10. 56 10. 68 10. 81 10. 93 11. 04 11. 14 11. 25 11. 35 11. 46 11. 56 11. 67 11. 77 11. 87 11. 98 12. 08 12. 18 12. 28 12. 38 12. 48 12. 58 12. 68 12. 78 12. 88 12. 98 13. 08 13. 18 13. 28 13. 37 13. 47 13. 57 13. 67 13. 76 13. 86 13. 95 V Cz RURAL VERTICAL DISPERSION COEFFICIENTS (METERS) f-mm> DOWNWIND ------------------------------- STABILITY DIST <KM> A B C D E pr 1. 050 503. 22 115. 31 63. 93 33. 12 22. 30 14. 39 1. 100 555. 30 121.35 66. 71 34. 12 22. 97 14. 82 1. 150 610. 08 127. 41 69. 48 35. 12 23. 62 15. 24 1. 200 667. 59 133. 50 72. 24 36. 09 24. 26 15. 66 :nv. 1. 250 727. 83 139. 62 74. 98 37. 05 24. 90 16. 07 1. 300 790. 83 145. 76 77. 72 38. 00 25. 52 16. 47 1. 350 856. 60 151. 92 80. 45 38. 94 26. 14 16. 87 1. 400 925. 14 158. 10 83. 17 39. 86 26. 74 17. 26 1. 450 996. 47 164. 31 85. 89 40. 77 27. 34 17. 65 1. 500 1070. 60 170. 53 88. 59 41. 67 27. 93 18. 03 1. 550 1147. 54 176. 78 91.29 42. 56 28. 51 18. 41 1. 600 1227. 31 183. 05 93. 98 43. 44 29. 09 18. 78 1. 650 1309. 90 189. 33 96. 66 44. 31 29. 66 19. 15 1. 700 1395. 34 195. 63 99. 34 45. 17 30. 23 19. 52 1. 750 1483. 63 201. 96 102. 01 46. 02 30. 78 19. 88 1. 800 1574. 79 208. 30 104. 67 46. 86 31. 34 20. 23 1. 850 1668. 82 214. 65 107. 33 47. 70 31. 88 20. 59 * 1. 900 1765. 72 221. 02 109. 98 48. 52 32. 42 20. 94 1. 950 1865. 52 227. 41 112. 62 49. 34 32. 96 21. 28 2. 000 1968. 22 233. 82 115. 26 50. 15 33. 49 21. 63 2. 050 2073. 82 240. 24 117. 89 2. 100 2182. 34 246. 68 120. 52 50. 96 51. 75 33. 96 34. 43 21. 92 22. 21 ****** 2. 150 2293. 78 253. 13 123. 14 52. 54 34. 90 22. 50 2. 200 2408. 15 259. 59 125. 76 53. 33 35. 36 22. 78 2. 250 2525. 47 266. 07 128. 37 2. 300 2645. 73 272. 57 130. 97 54. 10 54. 87 35. 82 36. 27 23. 06 23. 34 2. 350 2768. 95 2. 400 2895. 13 2. 450 3024. 28 279. 07 285. 59 292. 13 133. 58 136. 17 138. 77 55. 64 56. 40 57. 15 36. 72 37. 17 37. 61 23. 61 23. 89 24. 16 2. 500 2. 550 2. 600 2. 650 2. 700 2. 750 3156. 40 3291. 51 3429. 61 3570. 71 3714. 81 3861.93 298. 68 305. 24 311. 81 318. 39 324. 99 331. 60 141. 35 143. 94 146. 52 149. 09 151. 66 154. 23 57. 90 58. 65 59. 38 60. 12 60. 84 61. 57 38. 04 38. 48 38. 91 39. 33 39. 75 40. 17 24. 42 24. 69 24. 95 25. 21 25. 47 25. 73 2. 800 2. 850 2. 900 2. 950 3. 000 3. 050 3. 100 3. 150 3. 200 3. 250 3. 300 3. 350 3. 400 3. 450 3. 500 4012. 06 4165. 21 4321. 39 4480. 62 4642. 88 4808. 19 4976. 55 5000. 00 5000. 00 5000. 00 5000. 00 5000. 00 5000. 00 5000. 00 5000. 00 338. 22 344. 85 351. 49 358. 15 364.81 371. 49 378. 18 384. 87 391. 58 398. 30 405. 03 411. 76 418. 51 425. 27 432. 03 156. 79 159. 35 161. 91 164. 46 167. 01 169. 55 172. 09 174.63 177. 16 179. 69 182. 22 184. 74 187. 26 189. 78 192. 29 62. 29 63. 00 63. 71 64. 42 65. 12 65. 77 66. 42 67. 07 67. 71 68. 35 68. 98 69. 61 70. 24 70. 86 71. 48 40. 59 41. 00 41. 41 41. 82 42. 22 42. 62 43. 02 43. 42 43. 81 44. 20 44. 59 44. 97 45. 35 45. 73 46. 11 25. 98 26. 23 26. 48 26. 73 26. 98 27. 18 27. 39 27. 60 27. 80 28. 00 28. 20 28. 40 28. 59 28. 79 28. 98 4 H. 3 VAB.0001126615 RURAL VERTICAL DISPERSION COEFFICIENTS (METERS) DOWNWIND DIST (KM) 3. 550 3. 600 3. 650 3. 700 3. 750 3. 800 3. 850 3. 900 3. 950 4. 000 4. 050 4. 100 4. 150 4. 200 4. 250 4. 300 4. 350 4. 400 4. 450 4. 500 4. 550 4. 600 4. 650 4. 700 4. 750 4. 800 4. 850 4. 900 4. 950 5. 000 5. 500 6. 000 6. 500 7. 000 7. 500 8. 000 8. 500 9. 000 9. 500 10. 000 10. 500 11. 000 11. 500 12. 000 12. 500 13. 000 13. 500 14. 000 14. 500 15. 000 AB 5000. 00 438. 81 5000. 00 445. 59 5000. 00 452. 39 5000. 00 459. 19 5000. 00 466. 00 5000. 00 472. 83 5000. 00 479. 66 5000. 00 486. 49 5000. 00 493. 34 5000. 00 500. 20 5000. 00 507. 06 5000. 00 513. 93 5000. 00 520. 81 5000. 00 527. 70 5000. 00 534. 60 5000. 00 541. 50 5000. 00 548. 41 5000. 00 555. 33 5000. 00 562. 26 5000. 00 569. 19 5000. 00 576. 14 5000. 00 583. 09 5000. 00 590. 04 5000. 00 597. 01 5000. 00 603. 98 5000. OO 610. 96 5000. 00 617. 94 5000. 00 624. 93 5000. 00 631. 93 5000. 00 638. 94 5000. 00 709. 37 5000. 00 780. 42 5000. 00 852. 05 5000. 00 924. 22 t 5000. 00 996. 90 5000. 00 1070. 04 5000. 00 1143. 63 5000. 00 1217. 64 5000. 00 1292. 05 5000. 00 1366. 85 5000. 00 1442. 01 5000. 00 1517. 51 5000. 00 1593. 35 5000. 00 1669. 51 5000. 00 1745. 98 5000. OO 1822. 75 5000. 00 1899. 81 5000. OO 1977. 14 5000. 00 2054. 74 5000. 00 2132. 60 STABILITYr CD 194. 80 72. 10 197. 31 72. 71 199. 82 73. 32 202. 32 73. 92 204. 82 74. 53 207. 32 75. 13 209. 81 75. 72 212. 30 76. 31 214. 79 76. 90 217. 27 77. 49 219. 76 78. 08 322. 24 78. 66 224. 71 79. 24 227. 19 79. 81 229. 66 80. 39 232. 13 80. 96 234. 60 81. 53 237. 06 82. 09 239. 53 82. 65 241. 99 83. 21 244. 45 83. 77 246. 90 84. 33 249. 36 84. 88 251. 81 85. 43 254. 2 85. 98 256. 70 86. 53 259. 15 87. 07 261. 59 87. 61 264. 03 88. 15 266. 47 88. 69 290. 74 93. 95 314. 82 99. 03 338. 74 103. 94 362. 49 108. 71 386. 11 113.34 409. 58 117.85 432. 94 122. 25 456. 17 126. 56 479. 30 130. 76 502. 32 134. 89 525. 25 138.66 548. 08 142.36 570. 82 145. 99 593. 48 149.54 616. 06 153.04 638. 56 156. 47 660. 99 159. 85 683. 34 163.18 705. 63 166. 45 727. 85 169. 67 E 46. 49 46. 86 47. 23 47. 60 47. 96 48. 33 48. 69 49. 05 49. 41 49. 77 50. 08 50. 39 50. 70 51. 01 31. 32 51. 62 51. 92 52. 22 52. 52 52. 82 53. 12 S3. 41 53. 70 53. 99 54 * 28 54. 57 54. 86 55. 14 55. 43 55. 71 58. 46 61. 08 63. 60 66. 03 68. 37 70. 64 72. 84 74. 97 77. 05 79. 07 80. 89 82. 67 84. 40 86. 10 87. 76 89. 38 90. 97 92. 53 94. 06 95. 56 F 29. 17 29. 36 29. 35 29. 74 29. 92 30. 11 30. 29 30. 48 30. 66 30. 84 31. 02 31. 19 31. 37 31. 54 31. 72 31. 89 32. 06 32. 23 32. 40 32. 57 32. 74 32. 91 33. 07 33. 24 33. 40 33. 56 33. 73 33. 89 34. 05 34. 21 35. 76 37. 23 38. 64 40. 00 41. 16 42. 28 43. 36 44. 40 45. 41 46. 38 47. 33 48. 26 49. 15 50. 03 50. 89 51. 72 52. 54 53. 34 54. 12 54. 88 RURAL VERTICAL DISPERSION COEFFICIENTS (METERS) DOWNWIND DIST (KM) 15. 500 16. 000 16. 500 17.000 17. 500 18. 000 18. 500 19.000 19.500 20. 000 21.000 22. 000 23. 000 24. 000 25. 000 26. 000 27.000 28. 000 29. 000 30. 000 31. 000 32. 000 33. 000 34.000 35. 000 36. 000 37. 000 38. 000 39.000 40. 000 41. 000 42. 000 43. 000 44. 000 45. 000 46. 000 47. 000 48. 000 49. 000 50.000 STABILITY ABC D 5000. 00 2210. 72 750. 01 172. 85 5000. 00 2289. 08 772. 11 175. 98 5000. 00 2367. 68 794. 15 179. 08 5000.00 2446. 50 816. 14 182. 13 5000. 00 2525. 56 838. 06 185. 14 5000.00 2604. 84 859. 94 188. 11 5000. 00 2684. 32 881. 76 191. 05 5000. 00 2764. 02 903. 53 193. 96 5000. 00 2843. 92 925. 26 196. 83 5000. 00 2924. 02 946. 93 199. 67 5000. 00 3084. 80 990. 15 205. 26 5000. 00 3246. 33 1033. 19 210. 74 5000. 00 3408. 57 1076. 06 216. 10 5000. 00 3571. 50 1118. 78 221. 37 5000. 00 3735. 09 1161. 34 226.54 5000. 00 3899. 31 1203. 76 231.63 5000.00 4064. 15 1246. 03 236. 63 5000. 00 4229. 59 1288. 18 241. 55 5000. 00 4395. 59 1330. 19 246. 39 5000. 00 4562. 16 1372. 09 251. 16 5000. 00 4729. 26 1413. 86 255. 41 5000. 00 4896. 89 1455. 52 259.59 5000. 00 5000. 00 1497. 07 263. 72 5000. 00 5000. 00 1538. 51 267. 78 5000. 00 5000. 00 1579. 85 271. 78 5000. 00 5000. 00 1621. 08 275. 72 5000. 00 5000. 00 1662. 22 279. 62 5000. OO 5000. 00 1703. 26 283. 46 5000. 00 5000. 00 1744. 21 287. 25 5000. 00 5000. 00 1785. 08 291. 00 5000. 00 5000. 00 1825. 85 294.70 5000. 00 5000. 00 1866. 54 298. 36 5000.00 5000. 00 1907. 15 301.97 5000. 00 5000. 00 1947. 68 305. 55 5000. 00 5000. 00 1988. 12 309.08 5000. 00 5000. 00 2028. 50 312. 58 5000. 00 5000. 00 2068. 79 316. 04 5000. 00 5000. 00 2109. 02 319. 46 5000. 00 5000. 00 2149. 17 322. 85 5000. 00 5000. 00 2189. 25 326. 21 E 97. 03 98. 48 99. 91 101. 31 102. 69 104. 05 105. 39 106. 71 108. 02 109. 30 111. 33 113. 29 115. 20 117.06 118. 87 120. 64 122. 36 124. 05 125. 70 127. 31 128. 89 130. 44 131. 96 133. 45 134. 91 136. 35 137. 76 139. 15 140. 52 141. 86 142.90 143. 92 144. 93 145. 92 146. 89 147. 85 148. 79 149. 72 150. 64 151. 54 F 55. 48 56. 05 56. 62 57. 18 57. 72 58. 25 58. 78 59. 29 59. 80 60. 29 61. 26 62. 20 63. 11 64. 00 64. 86 65. 69 66. 51 67. 30 68. 08 68. 84 69. 46 70. 07 70. 66 71. 24 71. 81 72. 37 72. 91 73. 45 73. 97 74. 49 75. 00 75. 49 75. 98 76. 46 76. 94 77. 40 77. 86 78. 31 78. 75 79. 19 H.5 RURAL HORIZONTAL DISPERSION COEFFICIENTS (METERS) DOWNWIND STABILITY DIST (KM) A B C D E 0. 010 3. 36 2. 34 1. 47 0. 96 0. 72 0. 020 6. 29 4. 42 2. 80 1. 84 1. 37 0. 030 9. 08 6. 41 4. 08 2. 68 2. 00 0. 040 11. 77 8. 34 5. 33 3. 50 2. 61 0. 050 14. 39 10. 23 6. 56 4. 31 3. 22 0. 060 16. 96 12. 09 7. 77 5. 11 3. 81 0. 070 19. 49 13. 92 8. 96 5. 89 4. 40 0. 080 21.98 15. 72 10. 14 6. 67 4. 98 0. 090 24. 43 17. 50 11. 31 7. 44 5. 55 0. 100 26. 85 19. 27 12. 46 8. 20 6. 12 0. 110 29. 25 21. 01 13. 61 8. 96 6. 69 0. 120 31.63 22. 74 14. 75 9. 71 7. 25 0. 130 33. 98 24. 46 15. 88 10. 46 7. 81 0. 140 36. 31 26. 16 17. 00 11. 20 8. 36 0. 150 38. 63 27. 86 18. 12 11.93 8. 91 0. 160 40. 93 29. 54 19. 23 12. 67 9. 46 0. 170 43.21 31. 21 20. 34 13. 40 10. 01 0. 180 45. 48 32. 87 21. 44 14. 12 10. 55 0. 190 47. 73 34. 52 22. 53 14. 84 11. 09 0. 200 49. 97 36. 17 23. 62 15. 56 11. 63 0. 210 52. 20 37. 80 24. 71 16. 28 12. 16 0. 220 0. 230 54. 41 56. 62 39. 43 41. 05 25. 79 "4 26. 86 16. 99 17. 70 12. 69 13. 23 0. 240 58.81 42. 66 27. 93 18. 41 13. 76 0. 250 60. 99 44. 27 29. 00 19. 12 14. 28 0. 260 63. 17 45. 87 30. 07 19. 82 14. 81 0. 270 65. 33 47. 46 31. 13 20. 52 15. 33 0. 280 67. 48 49. 05 32. 19 21. 22 15. 85 0. 290 69. 63 50. 63 33. 24 21. 92 16. 38 0. 300 71. 76 52. 20 34. 29 22. 61 16. 89 0. 310 73. 89 53. 77 35. 34 23. 30 17. 41 0. 320 76. 01 55. 34 36. 38 23. 99 17. 93 0. 330 78. 12 56. 90 37. 43 24. 68 18. 44 0. 340 80. 23 58. 45 38. 47 25. 37 18. 96 0. 350 82. 33 60. 00 39. 50 26. 05 19. 47 0. 360 84. 42 61. 55 40. 54 26. 74 19. 98 0. 370 86. 50 63. 09 41. 57 27. 42 20. 49 0. 380 88. 58 64. 62 42. 60 28. 10 21. 00 0. 390 90. 65 66. 15 43. 62 28. 78 21. 51 0. 400 92. 71 67. 68 44. 65 29. 46 22. 01 0. 410 94. 77 69. 21 45. 67 30. 13 22. 52 0. 420 0. 430 96. 82 98. 87 70. 73 72. 24 46. 69 47. 71 30. 80 31. 48 23. 02 23. 52 0. 440 100. 91 73. 75 48. 72 32. 15 24. 03 0. 450 102. 94 75. 26 49. 74 32. 82 24. 53 0. 460 104. 97 76. 77 50. 75 33. 49 25. 03 0. 470 107. 00 78. 27 51. 76 34. 15 25. 52 0. 480 109. 02 79. 77 52. 76 34. 82 26. 02 0. 490 0. 500 111. 03 113.04 81. 26 82. 75 53. 77 54. 77 35. 48 36. 15 26. 52 27. 02 F 0. 48 0. 91 1. 33 1. 74 2. 14 2. 53 2. 92 3. 31 3. 69 4. 07 4. 45 4. 82 5. 19 5. 56 5. 92 6. 29 6. 65 7. 01 7. 37 7. 73 8. 08 8. 44 8. 79 9. 14 9. 50 9. 84 10. 19 10. 54 10. 89 11. 23 11. 58 11. 92 12. 26 12. 60 12. 95 13. 29 13. 62 13. 96 14. 30 14. 64 14. 97 15. 31 15. 64 15. 98 16. 31 16. 64 16. 97 17. 31 17. 64 17. 97 RURAL HORIZONTAL DISPERSION COEFFICIENTS (METERS) DOWNWIND STABILITY DIST <KM> A B C D E F 0. 510 115. 04 84. 24 55. 77 36. 81 27. 51 18. 30 0. 520 117. 04 85. 72 56. 77 37. 47 28. 01 18. 62 0. 530 119. 04 87. 21 57. 77 38. 13 28. 50 18. 95 t%w 0. 540 121. 03 88. 69 58. 77 38. 79 28. 99 19. 28 0. 550 123. 01 90. 16 59. 76 39. 45 29. 48 19. 61 0. 560 124. 99 91. 63 60. 75 40. 10 29. 97 19. 93 0. 570 126. 97 93. 10 61. 74 40. 76 30. 46 20. 26 0. 580 128. 94 94. 57 62. 73 41. 41 . 30. 95 20. 59 0. 590 130. 91 96. 03 63. 72 42. 07 31. 44 20. 91 0. 600 132. 88 97. 50 64. 71 42. 72 31. 93 21. 24 0. 610 134. 84 98. 95 65. 69 43. 37 32. 42 21. 56 0. 620 136. 79 100. 41 66. 68 44. 02 32. 90 21. 88 ft* 0. 630 138. 75 101. 86 67. 66 44. 67 33. 39 22. 21 0. 640 140.69 103. 32 68. 64 45. 32 33. 88 22. 53 0. 650 142. 64 104. 76 69. 62 45. 97 34. 36 22. 85 0. 660 144. 58 106. 21 70. 60 46. 61 34. 84 23. 17 0. 670 146. 52 107. 65 71. 57 47. 26 35. 33 23. 50 0. 680 0. 690 148. 45 109. 09 150. 38 110. 53 72. 55 73. 52 47. 90 48. 55 35. 81 36. 29 23. 82 24. 14 0. 700 0. 710 0. 720 0. 730 0. 740 0. 750 0. 760 0. 770 0. 780 0. 790 0. 800 0. 810 0. 820 0. 830 0. 840 0. 850 0. 860 0. 870 0. 880 0. 890 0. 900 0. 910 0. 920 0. 930 0. 940 0. 950 0. 960 0. 970 0. 980 0. 990 1. 000 152. 31 154. 23 156. 15 158. 07 159. 98 161. 89 163. 80 165. 70 167. 61 169. 50 171. 40 173. 29 175. 18 177. 06 178. 95 180. 83 182. 70 184. 58 186. 45 188. 32 190. 19 192. 05 193. 91 195. 77 197. 63 199. 48 201. 33 203.18 205. 02 206. 87 208. 71 111. 97 113. 40 114.84 116. 27 117. 69 119. 12 120. 54 121. 96 123. 38 124.80 126. 21 127. 63 129. 04 130. 45 131. 85 133. 26 134. 66 136. 06 137. 46 138. 86 140. 26 141. 65 143. 04 144. 43 145. 82 147. 21 148. 59 149. 98 151. 36 152. 74 154. 12 74. 49 75. 46 76. 43 77. 40 78. 37 79. 33 80. 30 81. 26 82. 22 83. 18 84. 14 85. 10 86. 06 87. 02 87. 97 88. 92 89. 88 90. 83 91. 78 92. 73 93. 68 94. 63 95. 57 96. 52 97. 46 98. 41 99. 35 100. 29 101. 23 102. 17 103. 11 49. 19 49. 83 50. 47 51. 11 51. 75 52. 39 53. 03 53. 67 54. 30 54. 94 55. 58 56. 21 56. 84 57. 48 58. 11 58. 74 59. 37 60. 00 60. 63 61. 26 61. 89 62. 51 63. 14 63. 77 64. 39 65. 02 65. 64 66. 26 66. 89 67. 51 68. 13 36. 77 37. 25 37. 73 38. 21 38. 69 39. 17 39. 64 40. 12 40. 60 41. 07 41, 55 42. 02 42. 50 42. 97 43. 44 43. 91 44. 39 44. 86 45. 33 45. 80 46. 27 46. 74 47. 21 47. 67 48. 14 48. 61 49. 08 49. 54 50. 01 50. 47 50. 94 24. 46 24. 78 25. 10 25. 41 25. 73 26. 05 26. 37 26. 69 27. 00 27. 32 27. 63 27. 95 28. 27 28. 58 28. 90 29. 21 29. 52 29. 84 30. 15 30. 46 30. 78 31. 09 31. 40 31. 71 32. 02 32. 33 32. 64 32. 95 33. 26 33. 57 33. 88 H. 7 A VAB.0001126619 r RURAL HORIZONTAL DISPERSION COEFFICIENTS (METERS) DOWNWIND STABILXT y------------ DIST <KM> A B C D 1. 050 217. 88 160. 99 107. 80 71. 23 53. 26 1. 100 227. 00 167. 82 112. 46 74. 31 55. 56 1. 150 236. 06 174. 62 117.10 77. 38 57. 86 1. 200 245. 07 181. 38 121. 71 80. 44 60. 15 1. 250 254. 03 188. 11 126. 32 83. 49 62. 43 1. 300 262. 94 194. 81 130. 90 86. 52 64. 70 1. 350 271.81 201. 48 135. 46 89. 54 66. 96 I. 400 280. 63 208. 11 140. 01 92. 56 69. 21 1. 450 289. 41 214. 72 144.54 95. 56 71. 46 1. 500 298. 16 221. 31 149. 06 98. 55 73. 70 1. 550 306. 86 227. 86 153. 56 101. 53 75. 93 1. 600 315. 52 234. 39 158. 04 104. 50 78. 15 1. 650 324. 15 240. 90 162. 51 107. 46 80. 37 1. 700 332. 75 247. 38 166. 97 110. 41 82. 57 1. 750 341. 31 253. 83 171. 41 113. 35 84. 78 1. 800 349. 83 260. 27 175. 85 116.29 86. 97 1. 850 358. 33 266. 68 180. 26 119. 22 89. 16 1. 900 366. 79 273. 08 184. 67 122. 13 91. 35 1. 950 375. 22 279. 45 189. 06 125. 05 93. 53 2. 000 383. 62 285. 80 193. 45 127. 95 95. 70 2. 050 392. 00 292. 13 197. 82 130. 84 97. 87 2. 100 400. 34 298. 44 202. 18 133. 73 100. 03 2. 150 408. 66 304. 73 206. 52 136. 61 102. 18 2. 200 416. 95 311. 01 210. 86 139. 49 104. 33 2. 250 425. 21 317. 27 215. 19 142. 36 106. 48 2. 300 433. 45 323. 51 219. 51 145. 22 108. 62 2. 350 2. 400 441. 66 329. 73 223. 82 148. 07 110. 76 449. 85 335. 93 228. 11 150. 92 112. 89 2. 450 458. 02 342. 12 232. 40 153. 76 115. 02 2. 500 466. 348. 30 236. 68 156. 60 117. 14 2. 550 474. 28 354.46 240. 95 159. 43 119. 26 2. 600 482. 37 360. 60 245.21 162. 25 121. 37 2. 650 490. 45 366. 73 249.47 165. 07 123. 48 2. 700 498. 50 372. 84 253. 71 167. 88 125. 59 2. 750 506. 53 378. 94 257. 94 170. 69 127. 69 2. 800 514. 54 385. 02 262. 17 173. 49 129. 78 2. 350 2. 900 522. 53 391. 09 266. 39 176. 29 131. 88 530. 50 397. 15 270. 60 179. 08 133. 97 2. 950 538. 45 403. 19 274. 81 181. 86 136. 05 3. 000 3. 050 3. 100 546. 38 554. 29 562. 18 409. 22 415. 23 421. 24 279. 00 283. 19 287. 37 184. 65 187. 42 190. 19 138. 13 140. 21 142. 29 3. 150 3. 200 3. 250 3. 300 3. 350 3. 400 3. 450 3. 500 570. 05 577. 91 585. 74 593. 56 601. 37 609. 15 616. 92 624. 67 427. 23 433. 20 439. 17 445. 12 451. 07 457. 00 462. 92 468. 82 291. 54 295. 71 299. 87 304. 02 308. 16 312. 30 316. 43 320. 56 192. 96 195. 72 198. 48 201. 23 203. 98 206. 72 209. 46 212. 19 144. 36 146. 42 148. 49 150. 55 152. 60 154. 66 156. 71 158. 75 F 35. 43 36. 96 38. 49 40. 01 41. 53 43. 04 44. 55 46. 03 47. 54 49. 03 50. 51 51. 99 53. 47 54. 94 56. 41 57. 87 59. 33 60. 78 62. 23 63. 68 65. 12 66. 56 67. 99 69. 42 70. 85 72. 28 73. 70 75. 12 76. 53 77. 95 79. 36 80. 76 82. 17 83. 57 84. 97 86. 36 87. 76 89. 15 90. 54 91. 92 93. 31 94. 69 96. 07 97. 44 98. 82 100. 19 101. 56 102. 92 104. 29 105. 65 RURAL HORIZONTAL DISPERSION COEFFICIENTS (METERS) DOWNWIND ------------------------------ STABILITY ------------------------- DIST (KM) A B -C D 3. 550 632. 41 474. 72 324. 68 214.92 160.80 3. 600 640.13 480. 61 328. 79 217. 65 162. 84 3. 650 647. 83 486. 48 332. 90 220. 37 164. 88 3. 700 655. 52 492. 34 336. 99 223. 09 166. 91 3. 750 663. 20 498. 20 341. 09 225. 81 168. 94 3. 800 670. 85 504. 04 345. 18 228. 52 170. 97 3. 850 678.50 509. 87 349. 26 231. 22 173. 00 3. 900 686. 13 515. 70 353. 33 233.92 175. 02 3. 950 693. 74 521. 51 357. 40 236. 62 177. 04 4. 000 701. 34 527. 31 361. 47 239. 32 179. 06 4. 050 708. 93 533. 11 365. 52 242.01 181. 07 4, 100 716.50 538. 89 369. 58 244. 69 183. 08 4. 150 724. 05 544. 66 373. 62 247. 38 185. 09 4. 200 731. 60 550. 43 377. 66 250. 06 187. 10 4. 250 739. 13 556. 18 381. 70 252. 74 189. 10 4. 300 746. 65 561. 93 385. 73 255. 41 191. 10 4. 350 754. 15 567. 67 389. 76 258.08 193. 10 4. 400 761. 64 573. 39 393. 78 260. 74 195. 10 4. 450 769.12 579. 11 397. 79 263. 41 197. 09 4. 500 776. 58 584. 82 401. 80 266. 07 199. 08 4. 550 784. 03 590. 53 405. 81 268.72 201. 07 4. 600 791. 48 596. 22 409. 81 271.38 203. 06 4. 650 798. 90 601. 90 413. 80 274.02 205. 04 4. 700 806. 32 607. 58 417. 79 276.67 207. 02 4. 750 813. 72 613. 25 421. 78 279. 31. 209. 00 4. 800 821. 11 618. 91 425. 76 281. 95 210. 98 4. 850 828. 49 624. 56 429. 74 284. 59 212. 95 4. 900 835. 86 630. 20 433. 71 287. 23 214. 92 4. 950 843. 22 635. 84 437. 67 289. 86 216. 89 5. 000 850. 56 641. 47 441. 64 292.48 218. 86 5. 500 923. 42 697. 34 481. 01 318. 60 238. 42 6. 000 995. 25 752. 50 519. 98 344. 45 257. 77 6. 500 1066. 14 807. 01 558. 57 370.05 276. 94 7. 000 1136. 17 860. 93 596. 81 395. 43 295. 94 7. 500 1205. 40 914. 30 634. 72 420. 59 314. 78 8. 000 1273. 88 967. 15 672. 34 445. 55 333. 47 8. 500 1341. 67 1019. 52 709. 67 470. 32 352. 02 9. 000 1408. 80 1071. 44 746. 74 494.92 370. 44 9. 500 1475. 32 1122. 92 783, 55 519. 36 388. 74 10. 000 1541.25 1174. 01 820. 13 543. 64 406. 92 10. 500 1606. 63 1224. 71 856.48 567. 77 424. 99 11. 000 1671. 48 1275. 04 892. 62 591. 76 442. 96 11. 500 1735. 83 1325. 02 928. 55 615. 61 460. 82 12. 000 1799. 70 1374. 67 964. 29 639. 34 478. 59 12. 500 1863. 11 1424. 00 999. 84 662. 94 496. 27 13. 000 1926.08 1473. 02 1035. 20 686.43 513. 86 13. 500 14. 000 14. 500 1988.62 1521. 75 1070. 40 2050.76 1570. 20 1105. 42 2112. 50 1618. 37 1140. 29 709. 79 733. 05 756. 21 531. 36 548. 78 566.12 15. 000 2173. 87 1666. 28 1175. 00 779.26 583. 39 F 107. 01 108. 37 109. 73 111. 08 112. 43 113. 79 115. 13 116.48 117. 83 119. 17 120. 51 121. 85 123. 19 124. 52 125. 86 127. 19 128. 52 129. 85 131. 18 132. 50 133. 83 135. 15 136. 47 137. 79 139. 11 140. 42 141. 74 143. 05 144. 36 145. 67 158. 69 171. 58 184. 34 196. 99 209. 54 221. 98 234. 34 246. 61 258. 79 270. 90 282. 94 294. 90 306. 80 318. 63 330. 41 342. 12 353. 78 365. 38 376. 93 388. 43 H.9 A 4 VAB.0001126621 RURAL HORIZONTAL DISPERSION COEFFICIENTS (METERS) DOwNWIND STABILITY -------------------------- DIST <KM> A B C D E F 15. 500 2234. 87 1713. 93 1209. 56 802.21 600. 58 399.88 16. 000 2295. 52 1761. 33 1243.98 825.06 617.70 411. 28 16. 500 2355. 82 1808. 50 1278. 25 047. 83 634. 75 422. 64 17. 000 2415. 80 1855. 44 1312. 39 870. 50 651. 73 433. 95 17. 500 2475. 45 1902. 15 1346. 40 893. 09 668. 65 445. 22 18. 000 2534. 78 1948. 64 1380. 27 915. 59 685. 50 456. 44 18. 500 2593. 82 1994. 92 1414.03 938.01 702.29 467. 63 19. 000 2652. 56 2041. 00 1447.66 960.35 719.03 478. 77 19. 500 2711. 01 2086. 87 1481.17 982.61 735.70 489.88 20. 000 2769. 18 2132. 55 1514. 57 1004. 79 752. 32 500. 95 21. 000 2884. 72 2223. 34 1581.03 1048.94 785.39 522. 98 22. 000 2999. 22 2313. 41 1647. 06 1092. 81 818. 25 544. 86 23. 000 3112. 73 2402. 78 1712. 68 1136.41 850. 91 566. 62 24. 000 3225. 29 2491. 49 1777.91 1179.75 883.38 588. 25 25. 000 3336. 95 2579. 57 1842.77 1222.84 915.66 609. 75 26. 000 3447. 74 2667. 04 1907. 27 1265. 70 947. 77 631. 14 27. 000 3557. 70 2753. 93 1971.43 1308.33 979.70 652. 41 28. 000 3666. 85 2840. 25 2035.24 1350.73 1011.47 673. 57 29. 000 3775. 23 2926. 03 2098. 75 1392. 93 1043. 08 694. 63 30. 000 3882. 87 3011. 29 2161.94 1434.92 1074.54 715. 59 31. 000 32. 000 33. 000 34. 000 35. 000 36. 000 37. 000 38. 000 39. 000 40. OOO 41. 000 42. 000 43. 000 44. 000 45. 000 46. 000 47. 000 48. 000 49. 000 50. 000 3989. 78 3096. 04 2224. 83 1476. 72 1105. 85 736. 45 4096. 00 3180. 30 2287. 43 1518.32 1137. 02 757. 21 4201. 54 3264. 09 2349.75 1559.74 1168.05 777. 88 4306. 43 3347. 42 2411.80 1600.98 1198.95 798. 46 4410. 68 3430. 31 2473. 59 1642. 05 1229. 72 818. 96 4514.32 3512. 76 2535. 12 1682. 94 1260. 36 839. 37 4617. 36 3594. 79 2596.40 1723.67 1290.87 859. 70 4719. 82 3676. 41 2657.44 1764.25 1321.27 879. 95 4821.72 3757. 64 2718.24 1804.66 1351.55 900.12 4923. 06 3838. 48 2778.81 1844.93 1381.72 920. 22 5023. 86 3918. 94 2839. 16 1885. 04 1411. 78 940. 25 5124.14 3999. 03 2899.29 1925.01 1441.73 960. 20 5223.91 4078. 76 2959.21 1964.84 1471.57 980. 08 5323.18 4158. 14 3018.92 2004.54 1501.31 999. 89 5421. 97 4237. 17 3078. 43 2044. 10 1530. 95 1019. 64 5520. 27 4315. 87 3137. 73 2083. 52 1560. 49 1039. 32 5618. 11 4394. 25 3196.84 2122.82 1589.94 1058. 94 5715. 49 4472. 30 3255. 77 2162. 00 1619. 29 1078. 49 5812. 43 4550. 04 3314. 50 2201.05 1648. 55 1097. 99 5908. 94 4627. 46 3373. 05 2239. 97 1677. 72 1117. 42 Estimating Concentrations Dovmwind from an Instantaneous Puff Releas TRINITY CONSULTANTS, INC VAB.0001126623 Estimating Concentrations Downwind from an Instantaneous Puff Release t. * (U.S.) Environmental Sciences Research Lab. Research Triangle Park, NC PB82-261959 P Aug 82 i U.S. DEPARTMENT OF COMMERCE National Technical Information Sorvfco T VAB.0001126624 EPA 600/3-82-078 August 1982 ESTIMATING CONCENTRATIONS DOWNWIND FROM AN INSTANTANEOUS PUFF RELEASE William B, Petersen Meteorology and Assessment Division Environmental Sciences Research Laboratory Research Triangle Park, North Carolina 27711 ENVIRONMENTAL SCIENCES RESEARCH LABORATORY OFFICE OF RESEARCH AND DEVELOPMENT U.S. ENVIRONMENTAL PROTECTION AGENCY RESEARCH TRIANGLE PARK, NORTH CAROLINA 27711 * p p rewtoouceo iy NATIONAL TECHNICAL INFORMATION SERVICE BA M'MMfT Of COMMERCE SMM0IEI.O. YA. SU1 4 VAB.0001126625 1EpXC|3<f/%-82-078 2' 4. title and suetitle ESTIMATING CONCENTRATIONS DOWNWIND FROM AN INSTANTANEOUS PUFF RELEASE 7. AUThORISI """" William B. Petersen 9. PERFORMING ORGANIZATION NAME AND ADDRESS Environmental Sciences Research Laboratory -- RTP, NC Office of Research and Development U.S. Environmental Protection Agency Research Triangle Park, NC 27711 12. SPONSORING AGENCY NAME AND ADDRESS Same as above * 3. RECIPIEN. T'S * ACCE-% SS. IO*N - ** N*O.4^^/* 5. REPORT DATE August 1982____________________________ 6. PERFORMING ORGANIZATION COOE S. PERFORMING ORGANIZATION REPORT NO. 10. PROGRAM ELEMftNt Klli. ! CDTA1 D/04-1315 (FY-8?)_______________ >1. CoWTEACT/EflJCFff'MO. " ........ . 13. TYPE OR REPORT AND PERIOD COVERED 14. SPONSORING AdCNCY COOK EPA/600/09 1 1 t VAB.0001126626 NOTICE THIS DOCUMENT HAS BEEN REPRODUCED FROM THE BEST COPY FURNISHED US BY THE SPONSORING AGENCY. ALTHOUGH IT IS RECOGNIZED THAT CERTAIN PORTIONS ARE ILLEGIBLE, IT IS BEING RELEASED' ** IN THE INTEREST OF MAKING AVAILABLE w AS MUCH INFORMATION AS POSSIBLE. * % l 0l * VAB.0001126627 NOTICE Mention of trade names or commercial products does not constitute endorsement or recommendation for use. ** u * VAB.0001126628 ABSTRACT This document provides an approach to estimating concentrations downwind of an instantaneous puff release. Dispersion of the puff is described by the Gaussian puff equation, using the dispersion parameters presented in Meteorology and Atomic Energy. The primary purpose of this work is to provide estimates of the instantaneous peak concentation or average concentra tion through the use of simple equations and nomograms. Example problems are provided to demonstrate the use of the equations and nomograms. A computer ized Gaussian puff model is also presented. m VAB.0001126629 CONTENTS Abstract......................................................................... Figures........................................................................... Tables.............................................................................. Acknowledgment............................................................. 1. Introduction...................................... 2. Concentration estimates....................... Instantaneous peak concentrations Conversion of concentration units Average concentrations..................... F 3. Instantaneous puff model..................... Puff equations...................................... Stability parameters...................... Model applicability.......................... 4. Computer algorithm.................................. Input data.................................................. References...................................................................... Bibliography................................................................ Appendices A. Execution of instantaneous puff model. Input data..................................................... Example of computer model output.... B. Source code listing................................ C. Changes to the dispersion parameters.. D. Puff model on programmable calculator. A *# * in vi vii t vm 1 3 3 6 7 13 13 18 19 20 20 25 26 28 30 31 49 57 58 Preceding page blank VAB.0001126630 Number FIGURES 1 x/Q versus downwind distance.......................................... 2 or versus downwind distance............................................ 3 Cumulative area under normal curve................. .. 4 az versus downwind distance............................................ 3 General flow diagram for Instantaneous Puff model 6 Input data .deck for Instantaneous Puff model......... a TABLES 1 DESCRIPTION OF INPUT DATA................................................. A-1 INPUT DATA FOR EXAMPLE PROBLEM...................................... A-2 COMPUTER MODEL OUTPUT......................................................... D-1 PROGRAM STEPS FOR HP-67..................................................... D-2 STORAGE LOCATIONS FOR INPUT PARAMETERS..................... 21 30 31 60 64 a VAB.0001126631 i ACKNOWLEDGMENT The author wishes to express his sincere appreciation to the many people who reviewed and offered suggestions for improvement of this document. Also, I would like to express my appreciation to Joan Emory for assistance. +* * Vll * * 4 * VAB.0001126632 A SECTION 1 INTRODUCTION * This document is provided in response to the need for making dispersion estimates of accidental releases of hazardous chemicals. Every year there are news stories of industrial or transportation related spills requiring the evacuation of nearby residents. The main objective of this work is to provide the air pollution specialist a methodology for estimating peak concentrations downwind of an instantaneous release. The model estimates are appropriate for travel times where the atmosphere can be assumed to be steady state. A number of factors affect the length of time the atmosphere will remain approximately steady: season of the year, latitude, synoptic conditions and local meteorology such as sea breeze and terrain flows. During periods of transition (such as sunrise or sunset) * stability, mixing height, wind profile, wind speed and wind direction are likely to change and therefore particular care should be exercised in charac terizing the atmosphere during these time periods. Persistence of atmospheric stability is discussed by Budney (1977). For situations where the travel time of the puff is greater than an hour, the factors which affect the dispersion and trajectory of the puff should be incorporated in the concentration estimates. The Gaussian instantaneous puff model is applicable for neutrally buoyant non-reactive releases. The dispersion of a small negatively buoyant release can be modeled using the puff equation provided the material mixes rapidly with the ambient air and disperses like a neutrally buoyant source. The equations, nomograms and methodology described in this document were j not designed for the fireman at the site of an accidental spill. He will not have the time nor the technical background to properly use the equations T li VAB.0001126633 rr and nomograms. The factors affecting his decision to order an evacuation will primarily be based on the size of the spill, the nature and toxicity of the substance. However, material provided in this document would be valuable to the air pollution specialist who is providing assistance to the fire department for the establishment of procedures to determine toxic corridors. The dispersion algorithms described would provide the basis for a model catered to the specific needs of the user. The computer algorithm described in Section 4 could also be adapted for on site use at a chemical plant using real time meteorology to predict dovnwind concentrations. The document is composed of three major sections. The first few pages of Section 2 describe a technique for estimating peak concentrations of instantaneous puff releases as a function of atmospheric stability and downwind distance. This discussion was designed so that estimates of peak concentre- % tion could be provided to the agencies vrfiich are directly concerned with the immediate health and welfare of the public within a matter of minutes after an accidental spill. These initial estimates could be provided without the aid of a computer. The remainder of Section 2 is concerned with estimating average concentrations and exposure. Section 3 provides a discussion of a generalized Gaussian puff equation with the same assumptions and limitations of the approach described in Section 2. The equations in Section 3 are the basis for a computer model described in Section 4. +* VAB.0001126634 A SECTION 2 CONCENTRATION ESTIMATES INSTANTANEOUS PEAK CONCENTRATIONS The peak ground level concentration from an instantaneous surface release is given by Equation 1. 2Q *P (1) Where: Q is the total emission (g). crx is the downwind dispersion parameter (m), 9y is the crosswind dispersion parameter (m), oz is the vertical dispersion parameter (m). Typically it is assumed that ax = cy for puff-type dispersion estimates. Nickola (1971) showed that, for ground level releases, crx is greater than a Oy in the first few hundred meters of travel, but the puffs become more symmetrical as travel distances approach 800 meters. For the purposes of this work ax and <jy are assumed to be equal, and the dispersion in the xy plane will be indicated by or. Equation 1 can then be expressed as: 2Q Xp (2)**/2 ff2 0z (2) 3 VAB.0001126635 Figure 1 shows peak ground level concentrations normalized by emission strength, Xp/Q, versus downwind distance for three stability regimes unstable, neutral, and very stable. The stability regimes can be determined from cloud cover, ceiling height and wind speed, using Turner's stability classification scheme (1970). In the absence of meteorological data at the site of release or from a nearby weather station, the stability regimes can be approximated as follows. On a clear, sunny day with light winds, use the unstable curves. During windy or cloudy conditions, use the neutral curves. On a clear night with calm or light winds, use the very stable curves. The dispersion coef ficients for the three stability classes are those recommended by Slade (1968). Figure 1 was derived using Equation 2 with the dispersion coefficients mentioned above. Equation 2 is applicable only for surface releases. Solid lines an the curve represent distances of observed data. Dashed lines are extrapolations. Example Problem 2-1 A 1000 kg instantaneous release of chlorine occurs during neutral stability conditions with a mean wind speed of 3 m/sec. What is the peak concentration 5 km downwind? Step 1. Use Figure 1 to determine X /Q at 5 km downwind on the neutral stability curve. Xp/Q = 9.5x10" Note; X /Q is independent of u. Step 2. Compute X^ = X /Q x Q *p = (9.5x10") x (1.0x10) s 9.5x10*2 g/m^ If the atmosphere was actually very stable rather than neutral, to what downwind distance would the peak concentration be greater than that computed in Step 2? i VAB.0001126636 mm m # X p/O lm '3 ) 10 10-5 1 10*6 10*1 10T7 nr2 10* 10'3 10* 10 10-10 10-5 0.01 0.1 1.0 10A DOWNWIND DISTANCE (km) 4 4 FIGURE 1. r Xp/Q VERSUS DOWNWIND OfSTANCE. THE LEFT HAND SCALE IS FOR Xp/Q VALUES OF 10* TO 10. THE RIGHT HANO SCALE IS FOR Xp/Q VALUES OF 10*11 TO 10* -5- IQ- 11 100 4 VAB.0001126637 Step 1. Step 2. Find r/Q (9.5x10*8) on Figure 1, on the very stable curve. Read down to the distance scale. x s 32 km. CONVERSION OF CONCENTRATION UNITS - The equation of state can be used for conversion of concentrations from ug/m^ to ppm. X(ppm) = x(nq/i3) x T(K) x R M x P(mb) where: T is the absolute temperature (K)y M is the gram molecular weight (gm-mole), P is the atmospheric pressure (mb), R is the universal gas constant 8.31x10"2 mb gm-mole K The equation to convert ppm X(ug/*3) = X(ppm) H x P(mb) I(K) x 8.31x10-2 In the example above the ambient temperature was 80F and the atmospheric pressure was 980 mb. Find the concentration in ppm. 1(C) = 5/9(1(F)-32) * 4 * VAB.00.Q1126638 * 4 Ihe absolute temperature is 299.7 <K). Ihe molecular weight of chlorine (CLo) is 70.91. 95000(pg/m3) x 299.7(K) x 8.31x10"2 70.91 x.980(mb) = 34 (ppm) The peak concentration 5 km downwind is 0.095 g/m-* or 34 ppm. A AVERAGE CONCENTRATIONS In the paragraphs that follow a methodology is described for computing ground level concentrations from an instantaneous surface release for a given stability class and sampling time. The average concentration over sampling time t can be expressed as some fraction of the peak concentration. XT = *p x F, * (3) where: xT is the average concentration for a given sampling time t, t is the sampling time* i.e. 5 min., 1-hour etc.,(expressed in seconds) Xp is the instantaneous peak concentration, F is the correction factor for sampling time, which always has a value less than or equal to one. The correction factor F can be computed as follows: F = (A-Q.5) (N) 0.3989 * -7- VAB.0001126639 I 1000 100 E 10 4 1 0.1 0.01 4* 0.1 1.0 10.0 DOWNWIND DISTANCE (km) FIGURE 2. Oj VERSUS DOWNWIND OISTANCE -8- rrm PPM p 100J) VAB.0001126640 NUMBER OF STANDARD DEVIATIONS AREA UNDER NORMAL CURVE ** * Figure 3. Percent area under normal curve for a given number of standard deviations. -9- VAB.0001126641 where: A N is the cumulative area under the normal curve (Figure 3), is the number of standard deviations out from the peak of the Gaussian distribution. u is the mean wind speed, or is the horizontal dispersion coefficient (Figure 2). The concentration at a given receptor location ranges from zero to a peak value as the puff moves towards the receptor. The peak instantaneoous concentra tion is always assumed to occur at time t when the center of the puff is at the receptor location. If the growth of the puff is small as the puff passes over the receptor, then the peak average concentration for sampling time r at a particular location occurs during the time period t - t/2 to t + t/2. Example Problem 2-2 For the conditions given in Example problem 2-1, find the peak 5 minute average concentration and the peak 1-hour average concentration at 5 km downwind. Step 1. Compute the instantaneous peak concentration jj-. From problem 2-1, xp = 9.5x10"2 g/m5. Step 2. Compute A. (a) Determine the number of standard deviations. tu 300(3) N s ------- -- --------------- = 3.0 2ar (2)050) ar is approximately 150 meters, determined from Figure 2 at 5 km downwind 4 t * VAB.0001126642 (b) Given a value of N = 3.0 determine A from Figure 3 A = 0.998 Step 3 Compute Xr* Substitute A into Equation 4 F = (0.998-0.5) (3.0) 0.3989 = 0.42 concentration minute average XT s 0-42 x 9.5x10*2 = 4.0x10*2 g/m^. In a manner analogous to the abovej the peak 1--hour average concentration can be computed. N = 3600 (3) 2a = 36 From Figure 3, A s 1 (1.-0.5) (36) 0.3989 0.035 Substitute F into Equation 3 to find the peak 1-hour average concentration. iT s 0.035 x 9.5x10*2 r 3.3x10*3 g/m3. '. .' * -11- \ * t VAB.0001126643 The total dosage, D, at a given downwind distance, stability class, and wind speed can be approximated using the following equation. 2,5 ffr (matter-time/volume) is determined for the given stability class and downwind distance. a * ** 4 t VAB.0001126644 A SECTION 3 INSTANTANEOUS PUFF MODEL The preceding section presented an approach to estimating peak ground level concentrations from instantaneous releases for a given sampling time. No mention was made of the basic assumptions inherent in the approach. Neither was there any discussion of the approach to computing concentrations out from the puff center for ground level releases or elevated releases. These topics were intentionally omitted from Section 2 for the sake of clarity and brevity. Also, it is likely that the peak concentration estimates for ground level releases are the most critical estimates in an emergency situation. This section will present a more generalized Gaussian puff model, allowing for factors such as mixing height, cross wind concentration estimates, and elevated releases. A computerized puff model is presented in Section 4 and an example output of the model presented in Appendix A. An example problem is also presented to demonstrate the use of the model. PUFF EQUATIONS The generalized puff equation is given as: -13- 4 VAB.0001126645 Following the puff, and assuming ax = ay, the puff equation can be written as follows: Q X(r, z, h) (2c2 Equation 2 is a simplification of Equation 6 for estimating pesk ground level concentrations from surface releases* The peak concentration at distances beyond the point where a2 is greater than Q.8L (mixing height) can be expressed as: X(x,0,0,0) = r for az > 0.8L i (7) The concentration at the ground from an elevated release at a radial distance r from the puff center is given by Equation 8. Q x (x, r, o, h) 2ir a* L for oz > 0.8L Equations 7 and 8 account for reflection from the top of the mixed depth layer and are appropriate for surface level releases during netural and unstable conditons. However, if the effective release height is small compared to the mixing height, Equations 7 and 8 are still good approxima tions. + VAB.0001126646 A 1000 100 10 0.1 0.01 0.1 ij 10.0 OOWNWINO DISTANCE (km) FIGURE 4 . Oj VERSUS OOWNWIND DISTANCE -15- maim 100.0 VAB.0001126647 Frequently, instantaneous releases are large enough in the horizontal and vertical dimensions that the initial size cannot be ignored in the con centration estimates. One approach to assessing the impact of the initial size on downwind concentrations is to introduce an initial horizontal dis persion parameter, oFo, and an initial vertical dispersion parameter, az cr can be approximated by dividing the total initial width (W) of the puff by 4.3, ar = W/4.3. oZq can be approximated by dividing the initial vertical extent of the puff (h) by 2.15, aTo s h/2.15. The total horizontal and vertical dispersion parameters are then given by: f 2 21/2 rt = r * ro ) oc and az are obtained from Figures 2 and 4 for the specified stability and downwind distance. A Example Problem 3-1 A nuclear power reactor has a sudden radioactive release of 1.5x10^ curies at 2 in the afternoon. The reactor building is hemispherically shaped with a radius of 20 meters. The existing meteorological conditions are unstable with a 1500 m mixing height and a 3 m/sec wind. From the weather forecast, it is an ticipated that the puff will pass over or near a receptor 10 km downwind. (A) What is the peak concentration 10 km downwind? If the puff release is about the same size as the reactor building then o7o - 20/2.15 s 9.3 m, and 0y = 40/4.3 = 9.3 m. From Figures 2 and 4, ar and oz are 670 m and 440 m, respectively. Using Equations 9 and 10, ffr s 670.1 and 0Zfc = 440.1. Since 440.1 is less than 0.8 times the mixing height, Xp can be determined from Equation 2, or Figure 1. Xp = 9.6x10*6 curies/nP. ' i. 4 (B) At 10 km downwind, what is the radial dimension of the puff where the concentration drops to 0,1 Xp? What area does the puff cover? For a surface concentration estimate, Equation 6 reduces to X " r)* o * az 6XP ["V2(t)2] r X = Xp exp If x/xp =0.1 then 0.1 = exp --1/2^--^2J A The expression above can now be solved for r. or at 10 km dowwind is 670 m. r = ar x 2.15 = 1440.5 m. a "* The radial dimension of the puff 10 km downwind is - 1440 m. t The area covered by the puff at this distance is = *r2 =6.5 km2. (C) What is the total dosage 10 km downwind, where the puff center passes? Using the unstable curve 10 km downwind on Figure 2, or = 670 m. Equation 5 can be used to compute the total dosage. 0 = 9.6x10"^ x 2.5 x 670 = 5.4x10**^ curie-sec/m^. 3 (D) If the puff center passes 1 km from a receptor, what is the estimated dosage at the receptor? For off-center computations of dosages, a more generalized form of the dosage equation can be used. 44 * ** * t ft VAB.0001126649 exp ( D = 3.1415 1.5x104 (670) (440) 3 r (looA21 exp L"1" r^j D s 1.8x10"^ curie-sec/m^. STABILITY PARAMETERS As mentioned before, the stability parameters used in the instantaneous puff model are those recommended in Meteorology and Atomic Energy (1968). Slade classified the data according to the broad categories of unstable. neutral, and very stable. A review of the data reveals two pertinent points (1) There was very little data upon which to base the az's during unstable conditions. (2) Much of the dispersion data during stable conditions lie closer to the Pasquil 1-Gif ford F curve than to the curve recommended by Slade. A plot of c2 versus downwind distance is shown in Figure 4. The figure was not presented in Section 2 because it was not directly needed for the analysis presented. The vertical dispersion parameters are embodied in the x/Q values in Figure 1. Figure 1 could, of course, be developed for any set of dispersion parameters appropriate for a given release. Appendix C lists the changes that would be required to change the dispersion parameters in the code of the puff model. -18- VAB.0001126650 A MODEL APPLICABILITY Estimating concentrations at point locations are very difficult because of the deficiencies in determining the trajectory of the puff. Puff trajectory is most important if concentration estimates are to be made at specific points. However, the modeling effort is significantly simplified if the magnitudes of the concentrations are needed without regard to exactly where the concentra tions will occur. Releases are seldom point sources, but are more typically small area sources. Small area source releases can be modeled to some extent by using initial dispersion parameters. The initial horizontal dispersion is typically calculated by dividing the initial horizontal dimension of the area source by 4.3. This method will give reasonable concentration estimates at downwind distances greater than about 3 times the horizontal dimension of the source. As with the lateral dispersion, the initial vertical dispersion parame ter is typically evaluated by dividing the initial vertical extent of the surface * release by 2.13. No model description would be complete without some guidance concerning areas of applicability. Many sources are not truly instantaneous. However, if the travel time is long compared to the release time then the puff model can be used to estimate concentrations. If the travel time to a receptor is on the same order or smaller than the release time, the Gaussian plume model can be used (see Turner, (1970). For the case where the release time is finite but smaller than the travel time, the instantaneous puff model will provide a worst-case estimate of peak concentrations for the same total release. It is difficult to evaluate the effect on average concentrations over a given sampling time for a finite release using simple models, since the puff is distorted in the downwind direction. Finally, I would like to reiterate that the modeling procedures outlined in the document are simple approaches to very complex problems. In general these techniques will yield worst case concentration estimates. The proper modeling of any sudden release requires the skills of an air quality specialist and a thorough understanding of the physical and chemical properties of the -release. .. t VAB.0001126651 SECTION 4 COMPUTER ALGORITHM The FORTRAN computer program consists of a main program and three sub routines. Figure 5 depicts the general flow of the model. The main program reads all input data and produces all output. The dispersion equations given in Sections 2 and 3 are solved in the main routine as well. Subroutine 06TMX computes the distance to maximum concentration for an elevated release. Sub routine PUFSIG is called by the main program for sigma y and z values. Sub routine AVCOR computes the area under the normal curve used in the computation of average concentration estimates. a INPUT DATA The main routine reads control information to determine output modes and a control to read new data or modify previous data. A source data card is then required giving information on source characteristics. A meteorology card is then required followed by cards specifying locations where concentra tion estimates are to be made. A description of each input card type is provided in Table 1. The last card of the data set (card type 6) is used only if I0UT3 on card type 2 is equal to 1. This sequence of input data cards is shown in Figure 6. All input data are in free format which is easy to use but care should be exercised to make sure each variable is given a value in the correct order. Each variable must be separated by a comma. A brief des cription of each input parameter is given in Table 1 with appropriate units. The metric system of units is used throughout the puff model. VAB.0001126652 * A TABLE 1. DESCRIPTION OF INPUT DATA KTL Input data control KTL=1 New problem, read all input data KTL=2 Change options only, use previous data KTL=3 Change options and source data KTLs4 Change options and meteorological data KTL=5 Change options and locations of concentration estimates KTL=6 Change options and meteorological data, and locations of concentration estimates KTL>100 STOP Card type 2 I0UT1,I0UT2,I0U13 I0UT1 If IOUTIsl a table of peak concentrations for different stability classes, sampling times and downwind distances is printed out I I0UT2 If I0UT2=1 concentration estimates are printed for the given input data only I0UT3 If IOUT3=1 A critical concentration must be input. The program will compute distance to critical concentration Card type 3 Q,H,SYOP,SZOP Q H SYOP SZOP Source strength Effective source height Initial or Initial oz (g) (m) (m) (ro) Card type 4 u,HL,AVT,KST u Wind speed HL mixing height AVT Sampling time for concentration estimates KST Stability class 1-3 (m/sec) (m) (sec) Card type 5 NREC,XR,RR,ZR L VAB.0001126653 TABLE 1 (Continued) NREC XR RR ZR Number of locations for which concentration estimates are to be made Distance downwind from release point (km) Radial distance from puff center (m) Height above ground (m) Card type 6 XCH1 XCH1 If IQUT3=1 read XCHI, critical concentration * * r ** 4 * * * 4 VAB.00Q1126654 A START READ CONTROL CARD YES CONTROL VALUE > 100 READ OUTPUT OPTIONS READ SOURCE CARD READ METEOROLOGY CARD READ NUMBER and Location of CONCENTRATION ESTIMATES IOUT3 EXECUTED YES READ CRITICAL CONCENTRATION OUTPUT DEPENDING ON OUTPUT OPTIONS STOP Figure 5.' General flow diagram for instantaneous puff, model. I VAB.0001126655 t i IF IOUT 3*1 CRITICAL CONCENTRATION CARD NUMBER ANO LOCATION OF CONCENTRATION ESTIMATES (5) f OUTPUT CONTROL CARD PROBLEM CONTROL CARD -4 * .f ^ ' * __ " '" . Figure 6. Input data deck for instantaneous puff model. Card type numbers are in parenthesis. * * * *9 t- 4 ^1 ' \ -24- . ' * * ,,* *' -L * * *** VAB.0001126656 r * A REFERENCES Budney, L. 3. 1977. Guideline for Air Quality Maintenance Planning and Analysis Volume 10 (Revised): Procedure for Evaluating Air Quality Impact of New Stationary Sources. EPA-450/4-77-001, U. S. Environmental Protection Agency, Research Triangle Park, NC 75 pp. Nickola, P. W. 1971. Measurements of the Movement, Concentration and Dimensions of Clouds Resulting from Instantaneous Point Sources. 3. Appl. Meteorol. 10: 962-973. Slade, D. H. 1968. Meteorology and Atomic Energy 1968. U.S. Atomic Energy Commission, Oak Ridge, TN 445 pp. Turner, D. B. 1970. Workbook of Atmospheric Dispersion Estimates. U.S. Environmental Protection Agency, Research Triangle Park, NIC 84 pp. 4 I VAB.0001126657 BIBLIOGRAPHY Accidental Episode Manual. 1972. Prepared for the U.S. Environmental Protection Agency by Resources Research, Inc., Research Triangle Park, North Carolina. 259 pp. Dumbauld, R.K., J.R. Bjorklund, H.E. Cramer, and F.A. Record. 197Q. Handbook for Estimating Toxic Fuel Hazards. NASA CR-61326, GCA Corporation, Bedford, Massachusetts. 496 pp. Hazardous Materials-Emergency Action Guide., 1977. U.S. Department of Transportation, Washington, D.C. 87 pp. Humphrey, P.A. 1973. Air Pollution Meteorological Observations for Short-Duration Investigations, Stagnation Episodes and Accident Emergencies. Presented at the Second Joint Conference on Sensing of Environmental Pollutants, Washington, D.C. 279-286 pp. Hutcheson, M.R. 1979. Analysis of Ensemble Averaged Concentrations and Fluxes in a Tracer Puff. EPA-600/4-79-002, U. S. Environmental Protection Agency, Research Triangle Park, North Carolina. 97 pp. Kaiser, G.D. and 8.C. Walker. 1978. Releases of Anhydrous Ammonia from Pressurized Containers-The Importance of Denser-Than-Air Mixtures. Atmospheric Environment 12: 2289-2300. King, R.F. 1972. Time-Sharing Isopleth-Area Program. ANL/ES-13, Argonne National Laboratory, Argonne, Illinois. 35 pp. Murphy, J.N., M.E. Harris, and D. Burgess. 1970. Hazards of Marine Trans portation of Liquid Chlorine. MIPR NO. Z-70099-9-93754, Department of Transportation U.S. Coast Guard, Washington, D.C. 67 pp. Preprints of Papers Presented at the Fourth International Symposium on Transport of Hazardous Cargoes by Sea and Inland Waterways. 1975. U.S. Department of Transportation, U.S. Coast Guard, Jacksonville, Florida. 571 pp. b> Sheih, C.M. 1978. A Puff Pollutant Dispersion Model With Wind Shear and Dynamic Plume Rise. Atmospheric Environment 12: 1933-1938. *4 Tw * 4* * 4 4h Slade, D.H. 1965. Dispersion Estimates from Pollutant Releases of a Few Seconds to Eight Hours in Duration. Technical Note 2-ARL-1, Air Resources Laboratory, Washington, D. C. 23 pp. Special Investigation Report Standardized Maps for Hazardous Material Accidents. 1979. NTS8-HZM-79-1, National Transportation Safety Board, Washington, D.C. 29 pp. Stevens, 3.B. 1980. Rapid Estimation of Hazard Corridors Following Chemical Releases. Presented at the 52nd Fire Department Instructors Conference, Memphis, Tennessee. A -27- * * VAB.0001126659 APPENDIX A EXECUTION OF INSTANTANEOUS PUFF MODEL An example problem is provided to demonstrate the use of the instantane ous puff model. Example problems 2-1 and 2-2 are used as input into the model. Also, a puff is modeled whose effective height of release is 50 m. Table A-1 shows the input data cards for these examples. The numbers in the left hand column of the table are the card type numbers. For a description of each card type see Table 1. Table A-2 presents the output of the model for these examples. The first ten pages of Table A-2 are a result of exercising option 1 on card r type 2. This part of the output lists peak concentrations for a variety of mixing heights, stabilities, wind speeds, sampling times, and downwind distances. While these listings are helpful in assessing the iapact of a puff release, they are optional and can be deleted from the output by assig ning a value other than 1 to I0UT1 on card type 2. The first part of the output for all of the options is a listing of the input data. ^ I Most of the input data and the output of the instantaneous puff model is straightforward. However, a brief discussion on a few points about the model should be profitable. The variable AVT (sampling time) on card type 4 must be assigned a value greater than zero. For peak concentration estimates, a value of 1-second for AVT is a sufficiently short time to give a good esti mate of the peak. If option 3 (I0UT3) on card type 2 is utilized, the model will predict the distance to the critical concentration specified on card type 6. When using option 3 for an elevated release, the model will also give the maximum concentration and the distance to the maximum concentration. You have probably already asked yourself the question for an elevated release, which distance does the-distance to critical concentration refer, to, since the " Be * VAB.0001126660 A critical concentration can occur at two distinct downwind distances? The distance to critical concentration is always greater than or equal to the distance to maxi mum concentration, thus assuring that the critical concentration will not be pre dicted beyond the estimated distance to critical concentration. pm * ** *- VAB.0001126661 4 CARD TYPE 1 2 3 4 5 i 2 4 i 2 1 2 3 4 5 6 1 TABLE A-1. INPUT DATA FOR EXAMPLE PROBLEMS 1 1,1,0 1000000.,0.,0 3.,1300.,1.,2 1,5.,0.,0. 4 0,1,0 3.,1500.,300. 4 0,1,0 3.,1500.,3600 1 0,1,1 100000050., 3.,1500.,300. 3,1.,0.,0.,3. 0.0001 999 ,5..0.,0 IkfA <b***4- p 2! "ftt* I t VAB. OOO1126662 i 4 I I Ii i I i Ik \ i i 1 ] i i t i i i * i i i 1ABLE A-2 C0MPU1ER MODEL OU1PU1 I ! I I i- 1 h t P I 4 f It j I I l It I II \ y 9 i i i U r i r J i H m r i l i i i ? I W 91 o i O h. H t yu ^C9ya Haw yOXzHu4x^Xr yO z2 IhQ v Ho H o; o n o yH O XXxc M UOOO C my y 9hu yo mmmw MN o o o hy yx n tvHNH MM M xI H H H XM oV) O H kl m O O O (J U MH X 9 M 9 9 H H X X 9) O Xt ' y h XXC* W Ml m M Hm <y c + J A in # 0c 1I amt mm * i OI OI o r* n# r* * r* * m <y ri iifty4 i + i * m ** i* m \ t i i4 * * -mm i i f !I I Cm x u HN ** 4 m jr 444 4 *< m 444 X oX 1 t 1 o in tn o o X ** rt o * XMn nH yu -\ o4 4 o4 in ^ * y -y y 9 N 9 Iff O 4 *4 a yn mm n 1 ~ in y * in - in n 4y oo 4 4 4 9 yy m r* 4* *y y m n* m* a* I I*t i p i xox 4 W # o * tn 4 I i ! 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P lA I ** * * *I~ lA * A Lt| | P*# *# - * * P* 99 #*# * \ ' ' *" * h o P A ^^ pP* l uu ##i*i r* p* till t^ill P> h ! i i ii til 9 o m r* til i* *+ ^ * ii * ** i Ml * ~ m pc r|%* * o Ao ^o r ~e uu -AW WX Ci x -a u WX PH M ` MM APi SM CM3 MIP - > A ^POrO*t*f^O* I, * 34 ii f1t I 4 t II I I *1 4 i 99 9 AI fIt PI At I ^PP *# 4 * ^ i 4 ' OO i rt *i ia m m r* ,, * o tliHiPt ; I 1*1 * p p *m IIIII t* # IItII I! l 333MO W III M\ *S l w u XM <H CM IIit m r r* i p* *i - i r* mi p DMA <Mf< -- --^ ** ^u cu VIA N VA *AAwC u HI I- C M i: * rr ii ! I !: t* , tt I aJ VAB.0001126666 A 1 t 1 *o * o * o * O *1 9 1 A 1 9 1 9 1 o 11 xv * i 9 * *1 * * *1 I i td ^ ^ IA 0 e o ol it i i i N 91 h 09999 9 9 O 9 O; I i * *j I t o 9 9 91 f t1iii [ 1 9 9 9 *1 9 9 ** 9 At i h I * -j Idif * A 9 Ml 1 I I O* ! i i * 1 Bt 1 *4 1 9 1 4 i !j "* 9 * * 9 9 9 9 t t 9* i I i t ! A ? * 1 1 i f I 9 O At 1 9t IIt II 1 1t ^ o ** * ** 11 l m 1H * i Ii \ j 7 m 1 0 1 * i *1 1 I 9 9 *i | A * ** 9 9 9 * 9*1 1* * * 9 9 **| h i t o * o 9 A 9^9 ,* 11t11 a 3 9 40 V * 9 9 * *B^Hi+ *M9* C | * -f MB * j co 1 99A oO** CJ 1 1 1 1 l> 9 9 * 9 9: 9 9 9 *i 9 * m m *;p * ** V h ! .. > * O 9 o- : 1i1 m ** *' A 999 i A T T Of fr l M ii m m O O * * ( 1 9i *i oi *i*! l bt i: AA fhft M_ _ _.*_4 eeo i i it i * m mbmb i i at ** *; n i< ^ I T! I: f| f| 0% M M J 0oooo 1 I II I1 ^r o9mm . fi I ! * * M A HI* . 0**00- ; i i ii i r* o o*o, -- - w w Si * * ** of m * m c* ti 4 III 9**09 MONO * JT * tfl HI til m o mi tn * * c X i | " 9 O' i *1h * 1 0 Jl -- -4i 9 o *i i 1i j * * 9 * *1 1 * O m * 9- t 7* * V * 9 m rt H o 0 * o oo* 1 ^bb + 9 9 1 9 1 All i 7 9 9 9 91 * 9 Of m 9 9 * 9. [1 b 1 *9 t a9 9 9 o O t 1_ ; ** ^t9 .-1 4T 9 * Alt 9 W 1 - * t j i 11 s ft - o oi i *9999 m9*99 mO*o* X X O tfl m ^f a^ Mft ^ 9 9 Al 9 9 n#ikn* * oom ia e n lA A A f * W - -U r hi WV *-- *99 J o uo A HU *. i r \ b XM 1 *9 I m in iiii 9 * in r* *** i II lI o 9 ~*9 9 0 0** r-- * I t tI I I 1 I ft 9 * IA a * IIIIt --O** Ift A * A I l i i* 0 9*' 9 *9* m ItII * 9 * * * lilt *-99*0 in *0*99 lA 9 a A llA**4A II r a 9 9*9 ft 9 9 9 O9*~ H n H i *90 I * * * I in o o o 9 ft 99 ^ in *o O ft * in f9 -t o CU -A w\ 9<c S 4w o hi X hi * 9 hi H fl 19 4 9 XH MOO X 9 * 9 CM3 EH 9H + ft ft * * in #A9 99 t 9 ii I 99 | 22 t i 0t m I 1 ** 9 (A * I * ** * I i 1* I * = ** 9 I O ^o CH AA V) X has X4m 9U X 9 hi M9 9 9* XM HHH CM3 XM I * * f t 4 I I* 35 VAB.0001126667 "O 3cH co CJ CMI Ld C3 * * ii N NM xx * *. III1I x x a m in m mi m 01 9I 01 9I 9I * h A A A I* 9ft x i9 fill rfl i* * + i ii i xa x 4 A 4 l A IA A I II i* m.i iI' ii lA mA i * + 1111 MflANh in +i * MIA* + 111 AA II ra il 4- 99 9* ++ 4 I I MMIA MAh * Mh *iA + I 1 MMMMh + * MM IA * X m IA * <A M ++ I HI KIM * Mh Ml +++ r* 4+ tA ** ** * 400 MMM hA+AMh^+ + Hi O+ + + O+ 9 M* AM* MA hh O OM O A+MA* A++ OA 9Mm+* *M+ +*a+ o o AAh A* A A 9090 ++++ O A u xu W w 91 X HAC X J ** 19 U HA 9) 9* 91 M X 91 HA 9 A JR &^ NMA W^A H4 M M c w3 * ** A* tJ O M n *0 0M AX XHNX ** m X ** Ml A A A + +i oo ++* Aox a N Ml o Ax 1 A ** Ml A 9 09 oAA AA * \A AAA H A" A A O# itiii ^M4 M9 *- 9 9 h h 4A 999 4 *** 9 9 9M9 I IIII 9 A AAh 11*11 W a +C * * 9 99 9A 999 A* I IIII MAMMA -i I 1 I It 94999 A94AA A AA A 4 +I I II 9 A9 * *4* + *9 9 Ml -M x <o U Ml 91 0k mi x ++++ a A*A A9O 4MA A A99 o + MAA4* g 9ft X * VI 93 91 X 9AX ae >4 u Ha UXu Xhu MA *4 M XM i Ma KX MXM X 91 3 o Vo u 0M A X X H M 9ft - Ml ft ft 0O00 ++ + 0 9ft ft o 0 0 m m+ ft 0 0000 * 0 Ml 0p 0 0 A 0 0 4 A AA A 9 *4111 9 AA A9 ri l 4 1111 9A9* 9A9* III I I 9AAJ 99 9 I IIII* II I 11 III I I *40*A*0A00 I1 3 X a A +I t A +1 I + I f A o a o X 14 W a 0 Xc X * tt 0 - u X Ha uXy X X 91 X *u . X H M 10 0 0 a X a CA , * XSi Hx MXM X3 I - Ml -- 00 0 00 * in x X 0 Ml A 0 Ml Ml 0 9# * Ml 0 m m 0 0 0 0 A0 0 0 9* r0 0 ** t: I* II i I9 It I- ii i* ( i I 36 VAB.0001126668 HPM 1 A 0 L E A -2 (C o n tin u e d ) it 99 X XI OO II 99 I I ttt -XX# lA 9 xnX A--M9 I t1 I I O O o 'xr imm i in1191o ( o 9O * 9X j 9 9 9 X) Jl IIIII in xt ~ xi t i i i ii 9 9 O 9 XI i 9 XI ^ O XI j 9 9 9 XI *; i I I I II 19 0 *XX I ^ XI f AO* I II mo *i 0o 1I * XI t I I I I. XAX IIIII 9X XoXX 9 * 9 XI iiiii m inX xi XI XI * ^ 44 Xt Xt II Iii o m a m mi II * XI II *9 9 XI i I II I 9 xto o 9 X NX H X f mm O^^X 0 0 99 9 111 i xi xt 9 xi x mmn 9 ~ XI *- O N n H aO IA OOOoo * X # XI XI 9 9 9 9 X X 9X X * # X X * x hx X4 in ** ^ + + x r x * x iiiiI XI 9 9 X) 9 ** 4# mm 9 * XI 9 9 wX xI xI I | XI 9 XI O X t I u X 9 XI ^ i: o xi o in 9 O O XI XI XI ^ 9 9 0 0 0 9 9in ^ 9 9 XI o * 9 9 XI I * t * r` I o ii i ^909 U XI 9 O I * XI I I X 4 X XI 9_ \ ! ~9~X| IZIZII o n xi oi xxi 9 -- <n * XI o o xi in 9 0 9 91 9 XI O 4 XI * 40 m ^O C III ~ y wv rX*i rX N+ mX xX ^ n r x - ~u W wx X ++ 0 099 9 * 9 9 XI XI --9 CX . mvi \Hi X) O 9 H4C X 4* U HOC X *4 W u HOC 14^ u *X 99 ma M m 99 HO M OU hn UXu xhu WHU SHU MXU SHU M9 900 M Ck D4X 9 *4 XI XI f * X.H 900 X4X N4 H 9 r x o *- 0 CH M X xi 9 K9X HHH i f CMS cms Cm3 i ii t . I* 'j *r- VAB.0001126669 i tiiii , -- 1~* ooo hIIrIr m *- }r ii *1111 mm w*h i: OMlit0 0 III -- -- r- II I A* - 99 AA* 909 t0n1 oui noni ioni ioai ** t i ii ii M N # f0* fi oooo *I I I **I I 1 I 1II 0o1 r * iiiii iiiti n m rt rt *-*- ***MI 9 0I 0I 0I I ii 9 9 * h; H 1; I 9 99 atH 9 t4*f I mm * 01 IA J) O) oo o o 11*11 m in m fi i i i I i m* r**ill^ 0*0* -- ~ iiri i m At ** IA Kitat 1 K 1 I *9I mI 0I1 I A0hft#0 tIIIi in m * <0 01 A I It I * r ii I t TABLE A-2 (Continued) * MN0* ~ i fr - 9 9 m i * ft w 9U M *; ; * At ~9 CU 9 \*9 9 9U N9 99 U9 _U 9 9 H9 59 9 0 ^ A ft X9 99 t: i t 4i * 9 99 n #9 I I 9 9 9 * 4 * 9 9 C 01 3 C93 Ii i *< 38 VAB.0001126670 r A (A I I I I. * -I t iii ti r tn ii itii mm o9H 1 t H N M DM4 I' 0i 0i 0i 9i 0i 1! Ml ^ f* II t II r o o tf> 9 KHrtHtf o --oom o till moor* co 4A ^ JT --CJ MONO o o m ia CM I III r h m mi 9 IA 9 9 9 0 1A 9 9 UJ a 4 o m I mom lA ^ ooooo m -- r* o -- HI m o mi r* o *** tI ahm^ u hi A N 4 U os C9 AH - o o m r* lA 9 O 9 *- O AA A X h^ X 9 p*9 9 O -- 9x m -- AAMM *A c X u X *C* 1u4 ^ 10 w XI V HOC XO O*J w HO UMU X H IA M 0X 9M 0 Cl COf MH vi r9 0^ 0x 0iftm0 IIIII o m p* o in 0 0 0 9 r- * * * * UNO* i i ii -- Ml om ^ mi mi ^ I I N fv) f ^ * eo oo oi i i i i i| h r* o o #*> i in - x m j o o m p* o J 9 O 9 m rn I t I I I II m IN i * 1 IIIII m O9 M IIIII r r m 9 e Ml 9 9 till 0099 moo** ii no m Ml 9 IA -- ++ i m Ml m i m U1 ~O 9 XO Oo OM MAAoi i -- 9 9rn m ; moomm OhOhH Ah AO A 9mm 9 Ml 9 -M PMh i o** *O O9 9O 9o .' I I I II *-> O MM l( 9 x- r O M*. , 9 ^ 9 r* t .j m ^ -- 9 * 9 I I O O " M MI O O O o O; * I I II o O MAM Q III O a X r* O m 9 9 ; * *i *ii 900 mo i i1 mi o o in m m t ................................................................. .... O A M 1T i ^AA ^ 1 O O O OI O* l OalmAtftO^O' ft - Ah * # * * - 4 * vs w m^1 Uo * it * 9 m -- <- . mM+ Atnoo oI * O A -h A * A ^ fl . ; Y 9^ -- *00 9 n 0 o 0 M9l 9 0 9 * MX**0 9 9 9 *- Cl mo9 9O^ p* mIfti 9j9r oo I'.' rX i _ .t. j m ^ Ml 9 9 . H* 9* i H ! AA A A-| ???+' 0 ia 9-- m0 ^0 9 mi ^ o ** oAA 9 Mfc 9 Cl c AV HOC X9w 19 U VI Ift fX I *u Cx 9X KO H mmm N A* moo ooo OA r* in -- T 1 I l 1 t tt i : [i It t I| VI I to I I I C 4 i i * i I 0 1 t t f 0 I * 1* * * \I H I1 to IJ t i* 1 i V pJ I -I t * * I L l !\ A t j ft4 4 # *t ii ii Y ii ft tI 4p -* * I * I 9* I ito I t I I I t * I# t i ip t iI t i1 i Iftftt t 1 * . I I I 19 U ft- Id 39 4 VAB.0001126671 iiiii ** * +* I #+ 1f*1m1r*1<r 1*1 (A* + I 4 I* ^ HK OI I OI OI * A rt - m r* i r o o o * t f t* n m + iii n til* I + tii tit* TABLE A-2 (Continued) i ifl - h rt *1**1 0 + I t 00 II * r* a 4* * +++++ ** * IA -- +++++ HI ++ t+ nn+* r+*A + m r r* * +++ N kft ~ f* m ~ U) m m m I i ** * * * 4 40 i 4 I1 t I I f 3 r i 1* II1: X**- *- * f I * VAB.00Q1126672 A I Ii I 13 3 oC CJ 1 uJ Q r- ! H #% aa ** I HXHU 9K\ f Oh XH 9 -* U W WId M S m U Uhi 1if4f C 4CHU 4SC o en X au wu h HUSO M flu X xa aama axnc Nwma kH mo Xau wi* aa aa xa w x~ Xac XX ja H4 ** m* ** 41 i!.- ; II * . I l V? *vr VAB.0001126673 1ADLE A~2 (C ontinued) OMH*O oMH H N 9 OX X c C h U (HI a x *4 a HU44 U U H* HH amm onelNx Hm * *. . 4 1 f + 1 .1 p k- V t1 .) + A a a oo N a *oo a m A o rt 4 a1 U H a t o 0+ j o o uy a 14 c a o aw a aX a caMa u ~XCa c <9 W u QU HM h X US9H r X-*4 H a X Kh C 4 MN4h # r i i Mi iU *j a a ap d 4 was n aa n ah aa 1 4 i i : 0t Hau a a u #* aMXc 3au a aa oaa aOH aa u u w a < i o' 1 h ' o * a ua * ** * 42 t (b i t * i i 4H * 1 jr 1 I mmiaiiviiia* . VAB.0001126674 A ,i *o G3J C o4coJ CMI UJ a X XUUN ^1X\9 OH HX o xuu- ux V o* m *4 M9 U*4 M0HXX>H* lA mAo *uuc*m(uawv0* A9wHXAMUXen^WoMWcNuuX A 3MX MXMeX ArACf *. * .* *V 9Xwc uwX U9 XMO AMXxh9 Xk9X AX XU M3X3 HXX9 ~ X** ~XX AoO 4 Q 4 (A OH QA ** I! i f I i( * ii n i. ii 4 * .** * 43 i k l i * iIt i lt i l I i I* VAB.0001126675 o ii * ! < j *so c ac CJ CMI UJ 0* * o i M a 1p 4 ! O HI O ZU 1 p* . J V - 4 #- c a tt+1 o a f 1 1 K m* M- H V cc W ^ ** MC .g 01 H n #n 9 O 1* 0 < O Xccc zzz ooo H HH H # t* fti X uoo9 m hnm N M tA N xx i4 *4 ooo UO H H mxha S 9 M M * ** OOSZ V> ft M H L A *. V ' a m aa * a a K> a1 u h. m o .1l oa 4 u O UAu a Men o HX w H c t m a U w ZC4 c (9 H U ri QHh M U )i M X O $* a XH * M 0 H ! X *4 M amaa xaca m i-i a h 3cwa ,* * xu 0HIMCv ah a HAM azv 0H| Xa AXH o3 n HOM aaa At u hi a x a HM ha aX U9 OX a a y+4 i 44 \ IilI \ It i i i * I I I I IM *m VAB.0001126676 II o 3cH CcoJ CMI UJ oGO M ++ *c I HC XX Uu 9 w Su ` f 9Oh*x* UUv 1*1* o* m n ou ^c outo wt-oc wcX w t* w u -> w r i: 9 Q 0M hw > U U HUSO t**M l0. 0X XHn4 xxr 3M WC t9o I * rO 19 9M W >91 9NUU 1H0 f9a* MX 93 -* 39C XX3 3 10 v OM IA ^. 45 h 1 t It* I* I II I \ \ tI f II 1I I i i t I 1tt \t * * 4 Ii Jfr I 1 I t II i VAB.0001126677 A a uco CMI ui CO = i oM9# ** ii I II1 HXM C9\ Vw XOu<ti OH UU HU CW UX * *\ lA U ww A K (9 * > U U HMX DX H4 XMa KMac C* xom. mu fa* H 9 XX * fa* w W 3fa* fa* U X3O tHMtvX 3O m 1 i i i i I *Ilt iiI i i ** 4 i I I I* t .-- 47 VAB.0001126679 I* 1 t + I f4 f I I * * I t ' i I -1 P ki- I 1 I *t 1I 4 * I *; 1j 4i iip i I i tiIh + j i i4 I It II I t P 1 it I 4 I ! i I4 I f * 4 ** I1 ( *ii I i \ 1 i + i f ** p 1I i l 4 I<S * t I p 4 I I 44 I Oh pr>i j4 11 1 ; 4 1 9 A 4 m * r X N i * 9 9* i i 9 X O N 4% H E X 99 i j wu 0 wX 0M X9 c X MM M; M Xo h o XoO c\* *f SEX 9 X u WX wc 9H O HXMn M X XX 10 w w 19 CH W0 MEX X XX *- U 0 9 9 o wO V) X M H a M Hu M W w W >9 XX w X H 9 J o o 4 w X MX 9 Xh X M X XX Xo oH XM X a H M ft* MO VI O H 4 P h uCOW woo m V) M M 0 X M x4 M UX MU HSU to 40 * U MMMMXX CH HX m> c c X X *4 M H X X o U i* w MHXC 1 P* i4 4 V) 10 iIut u0 * *' i* > 1 t 4I I * \ ? J VAB.000.1126680 4 APPENDIX B SOURCE CODE LISTING dimension klid(4), spu(6), xdis(12), xr(IQO), rr(ioo), 2R(icc), ch 00010 LIM(12), AVGT(5), YAN(2) 00020 DATA YAN / * YES' ,f NO*1 00030 DATA AVGT /60.,300.,900.,3600.,10800./ 00040 DATA XDIS /.01,.03,.05,.07,.1,.5,1.,3.,5.,7.,10.,30./ 00050 DATA IILID /500. ,1000. ,2000. ,4000./ OC060 DATA SPD /I.,3.,3.,10.,1.,3./ 00070 10 READ (5,330) KTL IF (KTL.GE.100) CO TO 320 00080 00090 c r KTL-1 NEW PROBLEM READ ALL INPUT DATA. 00100 00110 C KTL*2 CHANGE THE OPTIONS ONLY. ir \ KTL*3 CHANGE OPTIONS AND SOURCE DATA. 00120 00130 C KTL-4 CHANGE OPTIONS AND METEOROLOGY. r. KTL-5 CHANGE OPTIONS AND LOCATIONS OF CONCENTRATION 00140 00150 c ESTIMATES. 00160 G KTL-6 CHANGE OPTIONS, METEOROLOGY, AND LOCATIONS OF 00170 C CONCENTRATION ESTIMATES. 00180 C. 00190 READ (5,330) I0UT1,I0UT2,I0UT3 00200 c c I0UTI,I0UT2, AND I0UT3 ARE OUTPUT OPTIONS. A VALUE OF 1 c INDICATES THE OPTION UILL BE EXECUTED. 00210 00220 00230 r 00240 c I0UT1-1 TABLE OF CONCENTRATIONS FOR DIFFERENT STABILITY 00250 c CLASSES, SAMPLING TIMES, AND DOWNWIND DISTANCES. 00260 c I0UT2-1 CONCENTRATION ESTIMATES FOR THE GIVEN INPUT DATA ONLY 00270 c I0UT3-1 A CRITICAL CONCENTRATION MUST BE INPUT. THE PROGRAM 00280 c WILL COMPUTE DISTANCE TO CRITICAL CONCENTRATION. 00290 c 00300 GO TO (20,50,20,30,40,30), KTL 00310 c READ SOURCE CARD 00320 20 READ (5,330) Q,H,SYOP,SZOP 00330 c 00340 r. Q SOURCE STRENGTH (G) 00350 cH EFFECTIVE SOURCE HEIGHT CM) 00360 n SYOP INITIAL SIGMA R (M) 00370 c SZOP r. INITIAL SICHA Z (M) 00380 00390 GO TO (30,50,50,30,40,30) , KTL r. READ METEOROLOGY CARD 00400 00410 30 READ (5,330) U,1IL,AVT,KST C cU r. HL WIND SPEED MIXING HEIGHT C AVT r. SAMPLING TIME FO R CONCENTRATION ESTIMATES r. KST r. STABILITY CLASS 1-3 (M/SEC) (M) (SEC) 00420 00430 00440 00450 00460 00470 00480 00490 GO TO (40,50,50,50,40,40), KTL 00500 49 VAB.0001126681 rz.v3 downwind distance, radial distance from puff center c a;: U HEIGHT 40 READ (5,330) NREC,((XR(I),RR(I),ZR(I) ) , 1*1,"EEC) r 50 r. r. r 60 70 30 90 ioo * * NUMBER OF LOCATIONS FOR WHICH CONCENTRATION ESTIMATES ARE MADE DISTANCE DOWNWIND FROM RELEASE POINT (KM) RADIAL DISTANCE FROM PUFF CENTER (M) HEIGHT ABOVE GROUND (M) IF (I0UT3.EQ.1) READ (5,330) XCHI RCKI CRITICAL CONCENTRATION (C/M**3) IF (I0UT1.NE.I) I0UT1-2 IF (I0UT2.NE.1) I0UT2-2 IF (I0UT3NE.l) I0UT3-2 WRITE (6,340) YAN(I0UT1),YAN(I0UT2),YAN(I0UT3) WRITE (6,350) Q,H,SY0P,SZ0P WRITE (6,360) U,HL,AVT,KST WRITE (6,370) DO 60 I-l.NREC WHITE (6,380) I,XR(I),RR(I),ZR(I) CONTINUE C0Nl-2./(2.*3.14159)**1.5 C0N2-1./(2.*3.14159) CON3-l./(2.*3.14l59)**1.5 IF (I0UT1.NE.1) GO TO 180 DO 100 ILID-1,4 KLL-HLID(ILID) HLE-0.8*HLL WRITE (6,390) HLL DO 90 ISTA-1,3 DO 80 IDIS-1,12 XX-XDIS(IDIS) CALL PUFSIG (XX,ISTA,SR,SZ) ^Z-SQRT(SZ*SZ+SZOP*SZOP) SR-SQRT(SR*SR+SY0P*SY0P) E-EXP (-0.5* (II/SZ) **2 ) CHIM(IDIS)-Q*E*C0N1/(SR*SR*SZ) IF (ISTA.EG.3) GO TO 70 IF (SZ.GE.ULE) CLIM(IDIS)-Q*C0M2/(SR*Sll*HLL) CONTINUE CONTINUE WRITE (6,400) (ISTA,(Cl!IM(I), 1-1,12)) CONTINUE coimuuE DO 170 ILID-1,4 HLL-HLID(ILID) HLE-08 *HLL A * -1 A. * ^< _ 50 CO510 00520 00530 00540 00550 00560 00570 00580 00590 00600 00610 00620 00630 00640 00650 00660 00670 00680 00690 00700 00710 00720 00730 00740 00750 00760 00770 00780 00790 00800 00810 00820 00830 00840 00850 00860 00870 00880 00890 00900 00910 C0920 00930 00940 00950 00960 0C970 00980 00990 01000 VAB.OQO1126682 110 120 130 140 150 160 170 180 r 190 200 DO 160 ISTA-1,3 30 150 IS-1,2 IS'> (ISTA-1)*2+1S US-SPD(lSr) write (6,4io> hll,ista,us DO 140 IAVT-1,5 AVG-AVGT(IAVT) DO 130 IDIS-1,12 XX-XDIS(IDIS) CALL PUFSIG (XX,ISTA,S?,SZ) CZ*SQRI(SZ*SZ+SZOP*SZOP) SR~S0RT(SR*SR+SY0P*SY0P) E-EXP(-0.5*(H/SZ)**2) CI1IMAXQ*E*C0N1 / (SR*SR*SZ) IF (ISTA.EQ.3) GO TO 110 IF (S2.GE.HLE) CIIIMAX-Q*C0N2/(SR*SR*!ILL) CONTINUE AVGC*1. IF (AVG.LT.l.) GO TO 120 SGWT-AVG*US/(SR*2.) CALL AVCOR (SGWT,AVGC) CHEKIDIS )-CHIMAX* AVGC CONTINUE WRITE (6,420) (AVG, (CIIIM(I) ,1-1,12)) CONTINUE CONTINUE CO'JTINUE CONTINUE continue IF (IOUT2.NE.1) GO TO 230 URITE (6,430) KST,U,HL,AVT IILE-0.8*HL DO 220 IR-l.NREC XX-XR(IR) CALL PUFSIG (XX,KST,SR,SZ) SZSQR7(SZ*SZ+SZ0P*SZ0P) SRSQRT(SR*SR+SY0P*SY0P) IF (SZ-GE.HLE.AND.KST.LE.2) GO TO 190 El--0.5*(PvR(IR)/SR)**2 *2--0.5*(((ZR(IR)+H)/SZ)**2) F.3--0 5*( ( ( ZR(IR )-H) /SZ ) **2 ) Ci:i(Q*CON3/(SZ*SR*SR))*(EXP(El)*(EXP(E2)+XP(E3))) GO TO 200 CONTINUE El-EXP(-0.5*(RR(IR)/SR)**2) CHI-( o*C0N2 / ( SR* *2 *:IL ) ) *E 1 CONTINUE IF (AVT.LT.l.) CO TO 210 SGUTAVT*U/(SR*2.) CALL AVCOR (SGWT,AVGC) 51 'uc-ic ni020 01030 01040 01050 01060 01070 01080 01090 01100 OHIO 01120 01130 01140 01150 01160 01170 01180 01190 01200 01210 01220 01230 01240 01250 01260 01270 01280 01290 01300 01310 01320 01330 01340 01350 01360 01370 01380 01390 01400 01410 OU20 01430 01440 01450 01460 01470 01430 01490 01500 A VAB.0001126683 c::i-c:ii*avgc 210 -..RITE (6,440) XR(I:0 rr(i?o,z:<(ii\),ci:i 220 CONTINUE 230 continue IF (I0UT3.NE.1) GO TO 310 CL-0 XPK-0. I? (H.GT.l.) CALL D37MX (Q,KST,U,U,AVT,SYOP,SZOP,XPK,CL) IF (H.GT.l..AND.XCIII .GT.CL) GO TO 300 X-0 HLE-0.8 *liL KD-9 DO 280 K-1,KD DX-10.**(KD-K) DO 260 J-1,10 X-X+DX XI- X/10000. IF (XI.LT.XPK) XI-XPK XX-XI CALL PUFSIG (XX,KST,SR,SZ) SZ-SqRT(S2*SZ+SZ0P*SZ0P) SR-SQRTC SR*SR+SYOP*SYOP) E-EXP (-0.5 * ( H / S2 ) **2 ) CHI-(Q*C0N1/(SR**2*SZ))*E IF (KST.EQ.3) CO TO 240 IF (SZ.GE.HLE) CHI-Q*CON2/(SR**2*KL) 240 CONTINUE IF (AVT.LT.l.) GO TO 250 sgut-avt*u/ ( sr*2 .) CALL AVCOR (SGWT.AVGC) CHI-CHI*AVGC 250 DIFF*XCIII-C11I IF (DIFF) 260,290,270 250 CONTINUE 270 X-X-DX 280 CONTINUE 290 CONTINUE write (6,450) Q,H,STOP,SZO?,U,liL,KST,AVT,XC11I WRITE (6,460) XI,CHI IF (H.GT.l.) WRITE (6,470) XPK.CL CO TO 310 300 CONTINUE WRITE (6,480) XPK,XCHI,CL 310 CONTINUE GO TO 10 320 STOP C 330 FORMAT () 4 340 FORMAT ('1 *,8X,'OPTION l't5X,A3, 1 3*,5X,A3,///) 52 C1510 CI520 01530 01540 01550 01560 01570 01580 01590 01600 01610 01620 01630 01640 01650 01660 01670 01680 01690 01700 01710 01720 01730 01740 01730 01760 01770 01780 01790 01800 01810 01820 01830 01840 01850 01860 01870 01380 01890 01900 01910 01920 01930 01940 01950 01960 01970 01980 01990 02000 VAB.0001126684 A 35' -t+ 4 \ku Muyt (15::,'50lp.ce , / /, 5>:/sol-.silvern: (C)',T30,r no. l, /, 5x /source ::zic;:i (::)' ,t3o,f6.i,/,5::,'initial sicia r (*<)', 2730, F6.1,,/,5X/INITIAL SIGMA 2 (M)',T30,F6.1,///) 360 FORMAT (15X / ETEOROLOGICAL DATA' , / /,5X,' WIND SPEED (M/SZC) ' tT20, F 141,/,5X /MIXING HEICHT (M)',T30,F6.1,/,5X,'SAMPLING TIME (SEC)',T 228,F7.1,/,5X,'STABILITY CLASS',T33,I1,///) 370 FORMAT (T16, 'RECEPTOR DATA',/,T5 /LOCATION' ,T20/DOWNWIND' ,T35, 'RA 1DIAL' ,T50, 'HEICHT ABOVE' ,/,T6 / NUMBER' ,T20 / DISTANCE' ,T35* * DISTAKC 22 *,T54,'GROUND', /,T23 /(ICI)',T37,'(M)',T56,'(M)',/) 380 FORMAT (T7,13,T20,F8.3,T33, FS.2 ,T52,FS.2) 390 FORMAT (//////,5X,'MIXING HEIGHT (M)',2X,F6.0,/,IX'STAB.',T40,'DOW INWIND DIST*\NCE (KM) ' ,/,lX, 'CLAS' ,/,T8/0.01* ,T1S,'0.03' ,128/0.05 2' ,T38, '0.07* ,T49 ,'0.1* ,T59,*0.5' ,T69 ,'1.0' ,179/3.0* ,T89/5.0* ,199 3, *7.0' ,T108/10.0',T118/30.0\//) 400 FORMAT (2X,II,3X,1P12(E9.3,IX)) 410 FORMAT (////, IX/MIXING HEIGHT (M)',2X,F5.0,/,IX,'STABILITY CLASS' 1,2X,II,/,IX /WIND SPEED (M/SEC)',2X,F5.1,//,4X,'SMP.',T40,'DOWNWIN 2D DISTANCE (KM) ',/,4X, 'TIME (SEC) ' ,/,T13, '0.01* ,T23, *0.03' ,T33, '0. 305' ,T43f *0.07' ,T54, '0.1*,164, *0.5' ,T74,'1.0f ,T84,'3.0' ,194/5.0' #T 4104/7.0' ,T113, * 10.0' .T123/30.0',//) 420 FORMAT (2X,F7.0,2X,1P12(E9.3,1X)) 430 FORMAT ('1*,4X,'STABILITY CLASS' ,2X,II,/.5X/WIND SPEED (M/SEC)',2 IX,F51,/,5X /MIXING HEIGHT (M)',2X,F5.0,/,5X,'SAMPLING TIME (SEC)' 2,2X,F7.1,//,IX /DOWNWIND',T14 /DISTANCE FROM',131/RECEPTOR',T47 / 3CONCENTRATION' ,/ ,1X/DISTANCE' ,T15, 'PUFF CENTER.' ,T32 /HEIGHT' ,T50, 4 *(G/M**3)*,/,3X,'(KM)',T18 / (M)',T33 / (M)',/) 440 FORMAT (IX,F8.3,T14,F8.3,T31,F8.3,T48,1PE9.3) 450 FORMAT ('1',4X/EMISSI0N STRENGTH (G) *, :.'5 , F10.1,/,5X,' EMISSION HE 1IGHT (!I)*,T35,F6.1,/,5X,'INITIAL SIGMA R (M)',T35,F5.1,/,5X /INITI 2AL SIGMA Z (M) ' ,T35,F5.1,/ ,5X/WIND SPEED (M/SEC) ' ,T35,F5.1,/f5X/ 3MIXINC HEIGHT (M)',T35,F6.1,/,5X,'STABILITY CLASS T35.il,/,5X,' 4SAMPLING TIME (SEC) ',T35,F7.1,/,5X,'CRITICAL CONCENTRATION',* (G/ 5M**3)',T45,1PE9.3,/) 460 FORMAT (5X, 'CRITICAL DOWNWIND DISTANCE (KM) ' ,T45,F9.3,/,5X/C0NCE 1NTRATI0N AT CONVERGENCE (G/M**3) ' ,T45,1PE9 .3,////////) 470 FOPJIAT (///,5X/ ELEVATED RELEASE*,/,5X/DISTANCE OUT TO PEAK CONCE 1uTRATION (KM) *,F8.3,/,5X / PEAK CONCENTRATION (G/M**3) ',1PE9.3) 480 FORMAT ('1' ,5X/CRITICAL CONCENTRATION IS GREATER '/THAN PEAK CON 1CENTRATION',/,5X/ DISTANCE OUT TO PEAK CONCENTRATION (KM) *, F8.3, / 2,5X, 'CRITICAL CONCENTRATION (G/M**3) ' ,1PE9.3 , / ,5X,' PEAK CONCEMTRA 3TI0:: (C/Il**3) ' ,1PE9.3) 02010 02020 02030 02040 02050 02060 02070 02080 02090 02100 02110 02120 02130 02140 02150 02160 02170 02180 02190 02200 02210 02220 02230 02240 02250 02260 02270 02230 02290 02300 02310 02320 02330 02340 02350 02360 02370 02380 02390 02400 02410 02420 02430 SUBROUTINE PUFSIG (X.XST,S?MSZ) DIMENSION AY(3), AZ(3), BY(3), BZ(3) DATA AY /O.14,0.06,0.02/ DATA AZ /O.53,0.15,0.05/ 00010 00020 00030 00040 53 % A VAB.0001126685 DATA HY /O.92,0.92,0.9/ DATA 1SZ /O.73,0.70,0.61/ C C. PUFSIG CC!IPUTES SIGMA R AMP SIGMA Z, US IMG THE CURVES C. RECOMMENDED IN METEOROLOGY AND ATOMIC ENERGY (1968) ?. 175 C r X DOWNWIND DISTANCE r. KST STABILITY CLASS r. SR SIGMA R r. SZ SIGMA Z r (KM) Cl) CO XK-1000. *X GO TO (10,20,30), KST 10 SR-AY(1)*XK**BY(1) SZAZ(1)*XK**BZ(1) RETURN 20 SR*AY(2)*XK**3Y(2) Z-AZ(2)*XK**BZ(2) RETURN 30 SR*AY(3)*XK**BY(3) SZ-AZ(3)*XK**BZ(3) R ETURN r. SUBROUTINE AVCOR(SGWT,AVGC) r- i" AVCOR COMPUTES AREA UNDER NORMAL CURVE. SGWT NUMBER OF STANDARD DEVIATIONS r AVGC AREA UNDER NORMAL CURVE r R0.2316419 Rl-0.319381530 H2--0.356563782 B3-1.781477937 B4--1.821255978 B5-1.330274429 C-1./SQRT(2.*3.14159) X-SGWT C X IS THE DJUMBER OF STANDARD DEVIATIONS ABOUT THE MEAN *EXP(-(X**2/2.)> T-1./(1.+R*X) RR-C*E*(B1*T+32 *T**2+B3 *T**3+B4*T**4+B5*T**5) A*1.-RR AVGC-2.*(A-0.5)/(2.*X*0.398942) RETURN Anr>5n 0^060 00070 00080 00090 00100 00110 00120 00130 00140 00150 00160 00170 00180 00190 00200 00210 00220 00230 00240 00250 00260 00270 00280 00010 00020 00030 00040 00050 00060 00070 00080 00090 ' 00100 00110 00120 00130 00140 00150 00160 00170 00180 00X90 00200 00210 00220 00230 * ~3 o 4 54 VAB.0001126686 A routine opt:2: ( q , ::s i,, u, avt , syof ,s zo?, xi, cl ) o a UBT`X COMPUTES DISTANCE TO MAXIMUM CONCENTRATION c r. Q SOURCE STRENGTH (G) KST- STABILITY CLAES c r. U r AVT r. SYOP SZOP n s. XL CL EFFECTIVE PUFF HEIGMT UIXD SPEED SAMPLING TIME INITIAL HORIZONTAL DISPERSION INITIAL VERTICAL DISPERSION DISTANCE TO MAXIMUM CONCENTRATION MAXIMUM CONCENTRATION 00 (M/SEC) (SEC) 00 oo (KM) (G/M**3) CONl-2. / (2 .*3.14159 )**1.5 IA-1 XL-0.0 RC--0.0 X-0.01 DX-0.01 CL-RC xx-x CALL PUFSIG (XX,KST,SR,SZ) SR- SORT ( SPv* S R+SYOP* SYOP ) SZ-SQRT(SZ*SZ+SZOP*SZOP) E-EXP(-0.5*(H/SZ)**2) C-(Q*C0N1/(SR**2*SZ))*5 IF (AVT.LT.I.) GO TO 20 sgwt-avt*u/(s?*2 .) CALL AVCOR (SGWT,AVGC) RC-RC*AVGC 20 IF (RC-CL) 110,30,30 30 xl-x X-X+DX GO TO (40,60,30,100), IA 40 IF (X-0.192) 10,10,50 50 IA-2 0.2 DX-0.1 GO TO 10 50 I? (X-3.92) 10,10,70 70 IA-3 :>4. o GO TO 10 30 IF (X-19.2) 10,10,90 90 I A--4 COO 10 00020 00030 00040 00050 00060 C0070 00060 00090 00100 00110 00120 00130 00140 00150 00160 00170 00180 00190 00200 00210 00220 00230 00240 00250 00260 00270 00280 00290 00300 00310 00320 00330 00340 00350 00360 00370 no2?>Q 00390 00400 00410 0C420 00430 0C440 C0450 0046C 00470 VAB.0001126687  -- r* 4 * 10.0 GO TO 10 100 IF OI-3C5.0) 10,10,200 110 IF (DX-0.001) 120,120,130 120 RETURN 130 DX-0.1*DX 140 :x*x x-x-cz CL*RC x:>x CALL PUFSIG (XX,KST,SR,SZ) 9 S-SQRT(SR* S R+SYGP *SYOP) Z-SQP.T ( S Z*S Z+S ZOP* S ZOP ) Z*EXP(-0.5*(R/SZ)**2) *C-(Q*C0N1/(SR**2*SZ))*S IF (AVT.LT.l) GO TO 150 SGWTAVT*U/(SR*2.) CALL AVCOR (SGUT,AVGC) t*CRC*AVGC 150 IF (RC-CL) 160,140,140 160 IF (DX-0.001) 120,120,170 170 DX-0.1*DX ISO XL*X X-X+DZ CL*RC xx*x CALL PUFSIG (XX,KST,SR,SZ) s?*-SQRT( SR*SR+SY0P*SY0P) 3Z-SQRT(SZ*SZ+SZ0P*SZ0P) Z-EXPC-0.5*(H/SZ)**2) RC(Q*C0X1/(SR**2*SZ))*E SGWTAVT*U/(SR*2.) CALL AVCOR (SGWT,AVGC) nC-RC*AVGC IF (RC-CL) 190,180,130 190 IF (DX-0.001) 120,120,130 200 XL-999.0 CL-99.0 * * * # y V 4 a* C^4?0 0C5C0 00510 00520 00530 00540 C0550 00560 OG570 00580 00590 00600 00610 00620 00630 00640 00650 00660 00670 00680 00690 00700 0C710 00720 00730 C0740 00750 00760 00770 00780 00790 00300 00810 C0320 00330 00840 00850 00860 00370 nQ3$o CO 390 * VAB.0001126688 it- A APPENDIX C CHANGES TO THE DISPERSION PARAMETERS I* The horizontal and vertical dispersion parameters in the instantaneous puff model are of the form ax*3. The constants a and b are in data statements in Subroutine PUFSIG and can be easily changed. If more than three stability classes are desired* additional modifications to the code are required besides those given here. The constants a and b for the horizontal dispersion para meters are contained in arrays AY and BY respectively. Likewise the constants for the vertical dispersion parameters are in arrays AZ and BZ. Listed below are the DATA statements that contain the values of the constants a and b. DATA AY DATA AZ DATA BY DATA BZ UNSTABLE NEUTRAL VERY STABLE 0.14 0.53 0.92 0.73 0.06 0.15 0.92 0.70 0.02 0.05 0.89 0.61 To change the dispersion for the three stability classes change the values in the DATA statements in PUFSIG. 4 ** VAB.0001126689 * *9- APPENDIX D PUFF MODEL ON PROGRAMMABLE CALCULATOR The instantaneous puff model has been programmed on the HP-67 program mable calculator. In programming the puff model, two magnetic recording cards will be required. The dispersion algorithm is stored on the first card, and the code necessary to compute average concentrations over some sampling time is stored on the second card. The dispersion model can be executed without utilizing the second magnetic card, so that estimates of the peak concentration can be made using only the first magnetic card. Table D-1 provides the program steps necessary to generate the two programs. Table D-2 shows the storage locations for the input parameters. To execute the dispersion model after the program has been stored in program memory and the input parameters have been stored in their appropriate registers enter the downwind distance in (km) and press "A". The calculator will show the concentration in (gm"^). To perform another calculation for siother downwind distance, simply enter the distance and press "A". This process can be repeated for as many downwind distances as you require. * If average concentrations are needed, the second card must be read in after the completion of the dispersion algorithm. This routine uses informa tion generated by the dispersion routine. In addition, the wind speed must be stored in register 2 and the sampling time stored in register 3. After this information has been stored, press "A" to execute the program. VAB.0001126690 h m To calculate concentrations for different sampling times, store the sampling time in register 3 and press "A". This can be done for as many sampling times as needed. This process could be repeated for different wind speeds as well. b To demonstrate the use of the model run the dispersion program for example problem 3-1 (A). A 1. Read magnetic card with dispersion model. 2. Store stability (1) in sti. 3. Store source height (0) in register 6. 4. Store 0yQ and ff2o(9.3) in register 7 and 8, respectively. 5. Store Q (1.5x10^) in register 9. 6. Store mixing height (1500) in register E. 7. Enter 10. 8 Press A. * Xp = 9.619 x 10-6 g/m3 What is the 1-hour average concentration at this downwind distance. * Steps 1. Store wind speed (3) in register 2. 2. Store averaging time (3600) in register 3. 3. Read magnetic card with sampling time routine. 4. Press "A". X = 1496 X 10"6 g/m^ 4 * * l"1* * ** VAB.0001126691 1 * LE D-1 e *Le-fr 3701 k Ci 3 :4 &C5 d'?i' yly" S706<*p** 6eS 662 AF t 1 611 5 013 v* 014 1 /X 015 2CL0 01 IS X 01? $700 01$ *SSC eis RCL4 020 ` X* Q21 6crV*ki? 022 X* 02$ + 024 STOh 025 RCL5 02S X* 02? Rcie 028 X* 023 * 030 7V 031 $768 032 RCL4 333 X 034 1 /X 635 * RC10 030 X 037 S7O0 032 RCcc 83? RCLF T 041 X* S, * -5 6*3 5 CHS 64: X 04c e* 047 RCL3 048 X 045 DSP3 650 $cr 651 $7O0 052 r CL E vi e V* 7$ fcT -J5 35 tffi lb' t* ~CZ> 01 -c2 65 31 52 3o 66 -33 35 66 23 13 3o 64 53 36 c* ; ~s5 35 u 3$ 65 53 3b' 02 53 -53 r4 35 12 3b 11 -35 52 36 66 -33 35 66 3$ 3c 0iJCc- -24 53 -82 6^ 5-*L .Tw*Pw 37 Jo 66 -35 -t>3 "6i#L-3* * S3 Jo 15 r umo i p iUDEL CARD ONE 653 m -6.; 654 8 6$ 053 X 05c rclb Jo 12 657 x> r> lb-?4 65$ 6WD 22 14 65? RCL8 060 F.7N 36 0-**8*t 061 tLSLD 21 14 062 RCLO 3e 11 063 ROLE 3$ 15 864 X -35 065 Pi 16-24 066 X 06? 2 -35 02 068 X "3r 863 1/X 52 676 RCL3 3$ 0$ 671 X -35 072 $700 35 86 Ot ^ RTH 24 074 tLSLC 21 15 075 RCL1 36 01 07c I 81 077 8 88 07$ 8 06 875 8 60 080 S7xi 35-35 01 881 GTOi 22 45 882 *L8L1 21 01 883 m 62 884 3 OS 885 2 82 886 $70 35 11 08? 62 688 1 01 883 4 64 830 $T0B 35 12 891 -ci 832 7 07 893 3 894 STOC 63 o3 1 w 095 -ci 096 5 65 09' 3 63 098 S7CD 35 14 099 RCL1 3$ 01 108 RCLA 3$ 12 101 Y* 3: -102 MLB * 3$ 12. 163 X 104 $764 35 64 105 RCL1 3c 61 %" Reproduced from best eve copy 1 . A IA J VAB.00.Q1126692 TABLE. D-1 .Continued i 106 18? 1 4. fViCp Id? nb 121 112 2*2 f 4 -* 115 116 117 113 11? 120 121 122 122 124 125 126 12? 12S 12? 13 132 132 133 134 235 135 137 .138 13? 140 141 142 143 244 145 24c' 147 148 14? 156 152 152 153 154 155 * _+ 156 157 *CLC V*i X ECLO X STM ETN * i i * i A *3 t STOrt 0 ST08 ? 1 STOC Af 5 STM ECU ECLA V< RCLF X ST04 ECU RCLC yx ECID ST05 S7N *1513 # S ? S7C0 0 2 STOF 6 1 STOC 0 j. * STOD 36 i v 3? 14 -3c 35 85 24 22 82 82 82 35 12 -62 88 06 35 12 -52 87 35 22 -52 02 85 35 14 55 82 36 22 31 38 22 . -35 35 04 38 82 3S 13 32 36 24 -35 35 85 A4 4 21 63 08 8? 35 21 -61 88 82 35 22 -52 St 82 j5 24 -62 88 85 35 24 /. * 4* * CARD ONE 61 4 ic- cO ECU 15? ECLA 168 11 AV 161 ECLF 162 A+* 4 163 * d $704 * ECU 165 ROkf*r1U# rl-r 166 yx IS? RCLD les X 169 ST05 210 RTN 172 E/S 76 36 ti4fii* 3i 36 li -33 35 84 36 32 36 13 31 36 14 *35 35 @5 24 51 - * * 1 * *+ * p* VAB.OOO1126693 eei 881 884 885 866 88? 688 685 618 811 812 813 61 4 815 816 817 81$ 815 828 821 622 823 624 625 62S 62? 028 625 838 631 632 833 834 635 838 837 838 635 648 641 842 84 j 844 645 84 847 848 845 858 651 852 *Lw*Ciy*LtI1 .M-V y % isX r:CmL^*aZ RCL 3 Ji STOh 2 Pi X TX 1 /X sroc RCL8 ft 4 2 CHS e* S700 RCLb * 1 $ 4 i 3 X i *4 1'X $761 5 yx 1 9 3 3 6 21 4 4 2 . ? ' X RCL1 2i n 3$ 64 82 25 36 82 "35 36 63 -35 35 11 62 16-24 -35 54 52 35 13 36 11 5w 62 -24 MJK 33 35 14 5o 11 "62 62 63 61 66 84 61 65 -35 61 -55 52 35 81 85 31 61 "82 63 83 68 82 87 84 84 82 - 85' " w'3 36 61 TABLE D-1 (Continued) CARD TWO Reproduced from best oveiUblo copy. VAB.000,1126694 TABLE D-1 (Continued) CARD TWO A j* .T * 1, f- *t 63 * VAB.OOO1126695 TABLE D-2 STORAGE LOCATIONS FOR INPUT PARAMETERS INPUT Stability Class Source Height Initial Sigma Y Initial Sigma Z Source Strength Mixing Height FOR CARO TWO Wind Speed Sampling Time REGISTER sti 6 7 8 9 2 3 I i* * 3 ,* ** VAB.OQO1126696 Trinity Consultants Addendum to EPA 600/3-82-078 Prepared by Richard H. Schulze July 24, 1984 "Estimating Concentrations Downwind from an Instantaneous Puff Release" 1. p.30 Correct 3rd last line by inserting a comma after 5* The first integer 3 suggests three sets of three real numbers, and the comma specified was omitted in error. 2. p.21 Care should be exercised in selecting option IOPT3. This option does not use the variable for height above ground (ZR). Thus, if one is analyzing receptors above ground level using I0PT2, one can show lower values for I0PT3 because the maximum is only determined for ground level. 3. p.50 The computer calculates a sigma value by taking the square root of the sum of the squares of the Slade coefficients determined by PUFSIG and the initial sigma values input by the user (line 870 is one example). Another way used by Trinity Consultants in its work is to determine the distance a point source would have to travel to reach the designated puff size. This distance is called the virtual distance, and it is added to the actual distance for the purposes of determining the sigma values. The call to P1TFSIG under such a method would read CALL PUFSIG ( (XX+VX(ISTA) ,ISTA,SR,SZ) This scheme generally produces lower concentrations at greater distances than the EPA puff model. In one case with a virtual distance of 5 meters, plume height of 30 meters with unstable conditions, the Trinity method gave concentrations about 3 percent lover than the EPA method. -t TRINITY CONSULTANTS, INC mr REPORT FOR TRINITY CONSULTANTS Introduction * Arsine is a colorless gas which produces toxic effects on red blood cells (hemolysis) at low doses (1,2). The recommended threshold limit value (TLV) of arsine for an eight hour exposure in the workplace is 0.05 ppm (3). Exposure to 1 to 10 ppm of arsine for an hour is considered to be dangerous (4). The purpose of this analysis is to define and approximate what would be a "safe" or tolerable level of arsine exposure for a short period of time. Exposure Duration and Dose The dose of arsine received from inhaling contaminated air is a product of the airborne concentration x the breathing volume per minute x duration of exposure. One part per million (Ippm) of arsine in air is equivalent to 3.2 mg/m3 (4). An individual exposed to 0.05 ppm (TLV) for 8 hours would normally inhale 0.05 ppm x 3.2 mg/m3 x m3 = 1.28 mg of arsine. This value is based on a breathing volume of 20-25 m3/ 24- hour day; a number frequently used in environmental estimations. n For shorter periods of exposure, the physical activity of the individual is an important determinant of dose. The breathing volumes for an adult male resting, doing light work or doing heavy work are 7.4, 29 and 60 liters of air per minute, respectively (5). For an exposure of 1 ppm for one hour, the individual could theoretically inhale 3.2 mg/m3 x (0.0074, 0.029 or 0.060) m3 x 60 min = 1.42, 5.57 or 11.52 mg of arsine. If we select acceptable short term doses of 0.12, 0.25, 0.5 or 1.0 mg of arsine and conditions of "light work" (0.029 m3/min), the corresponding permissible levels in air for 0.5, 1.0 or 5.0 min exposure periods are: estimated dose mg of arsine 0.12 0.25 0.50 1.00 exposure duration 0.5 min 1.0 min 5.0 min 2.7 ppm 5.4 ppm 10.8 ppm 21.6 ppm 1.3 ppm 2.7 ppm 5.4 ppm 10.8 ppm 0.3 ppm 0.6 ppm 1.2 ppm 2.4 ppm The toxic properties of arsine are such that one should be mainly concerned with acute toxicity (1,2). Low levels of exposure are unlikely to lead to cumulative toxicity. This conclusion is reached because arsine readily reacts with body constituents such as the sulfhydryl groups of glutathione and the arsine molecule is then converted to inorganic arsenic and hydrogen. Thus, any cumulative toxicity would be the contribution of arsine intake to the body levels of inorganic arsenic. The principal source of human intake of arsenic is from the diet (6,7). Seafood, in particular, is rich in arsenic. An average total dietary intake of soluble (bioav&ilable) arsenic of 0.19 me/dav has been estimated (6.7). Conclusions The basic procedures for calculating dosages have been described. To define a tolerable dose, a finite period of measurement, for example, 0.5 to 5 min, should be established. One must also set an acceptable or tolerable dose of arsine intake, for example, 0.1 mg/day or 0.25 mg/day, then assume a breathing volume commensurate with exposure conditions. The period of exposure should be chosen such 1 p- that sampling and analytical methods can measure arsine levels in air. From the toxicologist's point of view, single acute doses of less than 0.25 mg/day are unlikley to cause harm. 1. Casarett and Doull's Toxicology. The Basic Science of Poisons, pg.438. 2. Patty's Industrial Hygiene and Toxicology. 3rd revised edition, vol.2a, pg. 1528-1531. 3. American Conference of Governmental Industrial Hygienists. Documentation of the Threshold Limit Values, fourth edition, 1980, pg.27, pg.225, pg. 337- 338. 4. American Industrial Hygiene Guide Series. Arsine. July-August, 1965. 5. Handbook of Biological Data. Lung Ventilation of Vertebrates, pg. 267. 6. L. Friberg ed. Handbook on the Toxicology of Metals. Elsevier/North- Holland Biomedical Press, 1979. 7. K.R. Mahaffey et al. Heavy Metal Exposures from Food. Environ. Health Perspectives 12:63-69, 1975. %A - \^JU- E.T. Wei, Ph.D. Professor of Toxicology School of Public Health University of California Berkeley, CA 947 20 July 21, 1984 *2 '4 (j4 OSo^r' A VAB.0001126700 Casarett and DoulVs TOXICOLOGY The Basic Science of Poisons AU substances are poisons; there is none which is not a poison. The right dose differentiates a poison and a remedy. Paracelsus (1493-1541) * VAB.0001126701 438 Toxic Acents possible effect has been confirmed in animals (Wills, 1966). Epidemiologic studies have suggested that arsenic in drinking water may be related to increased incidence of skin cancer (U.S. Public Health Service, 1962). Extra ordinarily high arsenic levels in soil and water have tentatively been linked with a severe form of peripheral arteriosclerosis (blackfoot disease) observed in Taiwan. However, members of the same family, some with blackfoot disease and some without, have similarly high scrum arsenic levels (Heydom, 1970). Arsine, the hydride of arsenic, is one of the more toxic arsenic compounds. Arsine maybe generated when acids are combined with arseniccontaining metals. Poisoning by arsine is the principal source of industrial arsenic poisoning today and has been reported in connection with the refining or processing of tin, lead, and zinc. Poisonings from this source have dire con sequences because of the severe hemolytic effect and the inadequacy of available therapy (Fore man, 1962). Arsine, a gas with a slight garlic-like smell detected only above safe levels, produces massive hemolysis and renal failure. Nausea, emesis, diarrhea, disturbance of the vascular bed, pulmonary edema, cyanosis, electrocardiogram abnormalities, hemoglobinuria, and liver dys function may occur. There is generally some delay in the onset ofsymptoms. Exposures as low as 10 ppm have produced delirium, coma, and death. If the exposure is not fatal, the signs of chronic arsenic poisoning may appear. Urine may continue to contain arsenic for some time after poisoning (Parry, 1963; A1HA, 1965). BARIUM Occurrence and Use. Barite (BaSO) and witberite (BaCOs) are the more common mineral forms of barium. Barium is used in various alloys, in paints, soap, paper, and rubber, and in the manufacture ofceramics and glass. Barium fluorosilicate and carbonate have been used as insecticides. Barium sulfate, an insoluble com pound, is used as a radiopaque aid to x-ray diagnosis. Barium is relatively abundant in nature and is found in plants and animal tissue. Plants accumulate barium from the soil. Brazil nuts have very high concentrations (3,000 to 4,000 ppm). Some water contains barium from natural deposits. Absorption, Excretion, Toxicity. The soluble compounds of barium are absorbed and small amounts are retained in the body. Reports in dicate the lung has an average concentration of 1 ppm (dry weight). The kidney, spleen, muscle, heart, brain, and liver concentrations are.0.10, 0.08, 0.05, 0.04, 0.03, and 0.03, respectively. Some barium is also found in the skeleton. Studies suggest that barium may be an essential element inasmuch as rats and guinea pigs maintained on barium-free diets fail to grow normally (Underwood, 1971). The soluble com pounds once absorbed are transported by the plasma. The biologic half-life is short (less thar> 24 hours). Feces appear to be the major excretion route of absorbed barium although some is lost through the kidney. The renal tubules reabsorb barium in the filtrate. The insoluble forms of barium, particularly barium sulfate, are not toxic by the oral route because of minimal absorption. However, the soluble barium compounds are highly toxic, in contrast to calcium and strontium, the other members of this group in the periodic table. Accidental poisoning from ingestion ofsoluble barium salts has resulted in gastroenteritis, muscular paralysis, decreased pulse rate, and ventricular fibrillation and extrasystoles. Potas sium deficiency occurs in acute poisoning and the heroic measure, treatment with intravenous potassium, appears beneficial. The digitalis-like toxicity, muscle stimulation, and central nervous system effects have been confirmed by experi mental investigation. Baritosis, a benign pneu moconiosis, is en occupational disease arising from the inhalation of barium sulfate (barite) dust and barium carbonate. It is not incapacita ting, but does produce radiologic changes in the lungs. The radiologic changes are reversible with cessation of exposure (AIHA, 1962; Browning, 1969). BERYLLIUM Occurrence and Use. Beryl (3BeO-AlaOs* 6SiOa) is the chief ore of beryllium. Its industrial uses include the hardening of copper, the manu facture of nonsparking alloys for tools, and the manufacture of lightweight alloys and nuclear reactors. It is also used in the manufacture of ceramics and in the electronics industry (transistors, heat sinks, and x-ray and cathode tubes). Gas lantern mantles, when first ignited, volatilize most of the beryllium they contain. Formerly, beryllium was widely used in the manufacture of fluorescent lights and neon signs. The aerospace industry uses beryllium compounds as propellants, providing a possible source of environmental exposure; however, coal combustion is probably the largest source of environmental beryllium contamination. Absorption, Excretion, Toxicity. Beryllium is not well absorbed when given by any route. Experimental animals may only absorb 1 percent as a maximum. After inhalation exposure beryl lium is retained in the lungs and mobilized slowly. In the bloodstream a colloidal beryllium phosphate is formed. In addition, small amounts m cc vi in H ol sk u; sc a h ti P it 0 b Q f e \ ( a c c t 1W 1 Itf1 S* c a a P > VAB.0001126702 ' > ,: w" : ^ '-. - '* / * * * ' * \ -* +. * *' * '* ' \ ^ f 4' ``h' ^ r t" J 1 * ^ I^ I --V ;*'e --^ - *,,. * .^a. *'.'/ ,` r " 1^ - f .P * '*5rsi-*rf&S*s?:,~-. -V * "*f\33k--j.*1-- . ~ -v*-* - *"*- .** * -_ . _ mi-p< *. -* , - * _/ 'WfijWv-'- ;-***'t-*---.?:= .?.. .* - ^, ' *- ' i*,<r.^V= - * -"v *V -4 -- -- r r?"y5*^' \* _**--r,V\-v---4'*v-. " P *s^ ** **' * * . 1,w1 h "**T * V **'*"" *- ''- , V sv>S . -* :r *T ._> * *ri ' ./ .^V** -** 'T p ^ /T. Wj ^* -i - V' f p * ***- 'I * r -L<- 1-? < rm * .V * - -- v rx;. * r j.- safeS-s v- V - .1 ' ^ M , t-lf -*-- v--;**v" - v ** -tfi, -t J J.' ** ( d-* r* f* (7 u >- i- * & * .* > f,.k- > r- i 'v " >/ -j p. *j J .rf ?' fc ^*5* : ovhi u -- .* a *-W >4? I* yffiS&s f'lf'F Hi!#! w Ctt?L, : Ik# " t-W u,`?*+$ i M iff" tf^4t * :S tf ; n +K hi j I- l*Ht-"< hil1- * Fl* r'j' ir;' '1# T__ ;w ^ .. . .T. V*1^' **& >11 i !> tsA--i fM :w,F: p,,, T-t i 'a-- Patty's Industrial Hygiene and Toxicology THIRD REVISED EDITION Volume 2A TOXICOLOGY GEORGE 0. CLAYTON FLORENCE E. CLAYTON Editors Contributors IL R. Beard R. P. BeUles M. |. Bvabec M. R. Brittelli K. I. Darmer, |r. W. I. Deichmann C Nine M. L KepRnger C | Kirwin^ |r. |. T. Noe C F. Reinhardt V. K. Rowe L L Sandmeyer H. E Stolcinfer E.R. White C. T. Youngblood J.A. Zapp A WILEY-INTERSCIENCE PUBLICATION |OHN WILEY & SONS, New York Chichester Brisbane Toronto X P '\ J ,;r . , . . . i: *OTP -S:J --L * ^. '. -* '/-r -. TiTti i-v TV r * -- ^1 .*- * *V>: * V-w -J * mt\ ''f >: 'i -- I - *! # 'f 4T **z *T* fc X* .N w-p Svj 152S HERBERT L STOKINCHI and to copper acetoarsenite (149, 150) or to mixtures of them. Copper acetoarsenite (along with sodium arsenite and Pb and Ca arsenates) figured prominently in the insec ticide discussed in Reference 148, with exposures in excess of 5 mg As/m* until the late 1940s. Finally, in implicating As as a carcinogen for man, a number of items emerge from the metabolic and epidemiologic studies just summarized that bring into sharper focus what appears to be the actual role of As in cancers from industrial exposures. First, As compounds vary greatly in their capacity to initiate human cancer. As a prominent example, there is no evidence that As,0, per se can induce respiratory cancer in either humans or animals; promoters in the form of smoking or as irritant acid gases, and/or associated metals, Cu, Fe, and Pb, have been identified with excesses of respiratory cancer (145-147); when such promoters are absent, mortality from respiratory cancer shows no excesses over statewide rates. Further substantiation of this assertion is the lack of demonstrated As,0, cancers in animals not exposed to these .promoters (138, 139) and the observation of higher dietary intake of Se by animals than by humans without cancer production (136). A second factor, overlooked in past, highly uncritical reviews (151), is the pinpointing of certain arsenicals that can apparently elicit respira tory cancer without promoters; copper acetoarsenite (Paris green) (123, 149) and lead arsenate (148, 150) are two such compounds. Third, those arsenicals, whether requiring promoters or not, must be classed as human carcinogens of low potency; five inde pendent investigators (123, 145, 146, 149, 152) estimated the latent period of exposure to be between 35 and 41 years at exposure levels well above the then-permissible TLV of 0.15 mg As/m*. 3.6 Hygienic Standards The Threshold Limits Committee of the American Conference of Governmental Industrial Hygienists, recognizing the distinctly different health hazards associated wnfti AstOa production and its handling and use, recommended in 1975 a TLV for As*0^ production of 0.05 mg As/m* with the carcinogenic classification of Ala, and with the proviso that SbtOt and SO* be kept below a ceiling of 0.05 mg Sb/m* and 5 ppm SObThe Ala designation refers to a carcinogenic classification for those substances proven carcinogenic for workers and for which a TLV has been assigned. For AsOa, handling and use, a TLV of 0.25 mg As/m* was recommended. A NIOSH criteria document, issued in 1973, recommended especially the same limit as that for As,0, production of 0.05 mg As/m* for "arsenic." In 1975, a revised and updated NIOSH document recommended an air standard of 0.002 mg As/m*, again making no distinction between health hazards associated with different types off exposure. 3^ Arsine, AsH, Arsine is a colorless, flammable gas with a garlic-like odor, now believed to be attributa ble to its tellurium content. AsH, deposits As on exposure to light and moisture. THE METALS 3.7.1 Sources and Ir The formation and lit because of As contamu contacts these As-bear formed by hydrolysis arsenide (153); in the (155); in the purificat leaching of Zn from its silicon prepared electn 3.7.2 Physical and C See Table 29.3.2. 3.7.3 Determinatiof Modification of 1 m tion 3.4) is appLJlole 3.7.4 Physiological 1 AsH, is a powerful he form, mortality rate is ' * **- - Acute Effects in Ma abdominal cramps, n.i The time of onset vai exposure. Jaundice us colored red or green ar skin, pyrexia, and sev delerium followed by after onset of anuria, interference with hem tein nitrogen level ci indicating kidney da or mild, elevation ol long as 18 months degeneration and care Chronic Effects in are to be found (157. onset, developrr % oi has included bio* ,, tra VAB.0001126704 * t 1- 1%^ ,, 1 'I L A. * ' ,1 ... - V^irT n_- IT: **J*4 ^4 * *+ y - 4'\ -4 - -k gt ^ .; *. r-rrv:w ri. ' -I -_ V ,J .-"t V trjl* ` - a_ IrV. V V i*i is'VT, * - | J . t- L -Lfc* - TV i i r-r *' %r * -- ,/i `a-a. fr m- THE METALS 1529 3.7.1 Sources and Industrial Exposures The formation and liberation of AsH occurs commonly in the metallurgical industry, because of As contaminaticm of many ores, Zn, Pb, Cu, Sb, Au, Ag, and Sn, when add contacts these As-bearing ores or metals. AsH* may also be liberated when H+ ion is formed by hydrolysis of As intermetallics, as in the reaction of moisture with caldum arsenide (153); in the process of wetting A1 and phosphate dross (154); in Pb refining (155); in the purification of Sn (156); during cyanide extraction of gold (157); in the leaching of Zn from its ores (158); in the cleaning of tanks and furnaces; and from ferrosilicon prepared electrolytically (159, 160). 3.7.2 Physical and Chemical Properties * s -A &* , >7 r* a V^-44-1 I. ' ,V rr-T < a. 7.V t -t. See Table 29.3.2. 3.7.3 Determination in the Atmosphere Modification of the method of atomic absorption spectrometry discussed under As (Sec tion 3.4) is applicable to the determination of AsH*. 3.7.4 Physiological Responses AsHa is a powerful hemolytic agent in both acute and chronic exposure, and in the acute form, mortality rate is high. Acute Effects in Man. The prominent, first signs of acute poisoning are malaw, abdominal cramps, nausea and vomiting, and a red staining of the conjunctiva (156). The time of onset varies from a few minutes to 24 hr depending on the severity of exposure. Jaundice usually appears on the second or third day. The urine may be colored red or green and in some cases anuria occurs. There may be pigmentation of the skin, pyrexia, and severe anemia; edema of the lungs is common, and in fatal cases, delerium followed by coma. Death usually occurs from myocardial failure a few days after onset of anuria. The anemia is due to hemolysis of mature red cells and not to interference with hematopoiesis. Leukocytosis may also be observed (161). The nonpro tein nitrogen level of the blood shows a marked rise when hemoglobinuria is present, indicating kidney damage from hemolysis products. In all cases, fatal or nonfatal, severe or mild, elevation of the T-wave of serial EKGs was found. Survivors followed for as long as 18 months gave evidence that AsHa was the causal agent of myocardial degeneration and cardiac failure (162). A5. 4 _v*_ * ^ % + Wv f-_ * JT Chronic Effects in Man. Very few literature references to chronic AsHt exposure are to be found (157, 163). The main differences from acute poisoning are a delay in * -a onset, development of peripheral neuritis, and rapid recovery under treatment, which has included blood transfusions and dithiol administration. p. 4 F;r='" rr 'i a* ** i rh>r- j.. ^ v- ti .A^ 1 t?^ . 4- -l I' -r * * * I j*s* i* fr * r'* * '&*Ki *w f.f * Ste10: - .t : - - <3l*'_ - V- -> - . - , V*'* # * -d^t-w *' > * '. H *^-4 .J- . ^ |t i\: -- -* .P * -f 4 .' |- * V 1530 HERBERT E. STOKINGER 3.7.5 Hygienic Standard and Warning Properties v The recommended TLV of 0.05 ppm as As was adopted in 1961 by the ACGIH on the basis that urinary As values could have resulted from exposure concentrations below* 0.25 ppm (164). The odor threshold of 0.5 ppm (165) cannot be considered to serve as a suitable warning property. REFERENCES Data supplied by Asarco, New York, 1977. R- F. Tarrant and J. Allard, Arch. Environ. Health, 24,277 (1972). 102. D. J. Birmingham et al., Arch Dermatol. 91,457 (1965). 103. H. E.Stokinger, unpublished wort, 1961, Cincinnati, Ohio. 104. Handbook of Chemistry and Physict. R. C. Wea, Ed., 55th cd., C.R.C. Press, 1974-1975. 105. "NIOSH Criteria Document for Occupational Exposure to Inorganic Arsenic-New Criteria pp. 100-110. 19" 5. 106. In H. A. Satterlee, Arch. Ind. Health, 17,218 (1958). 107. InJ. W. E. Harrison et al.. Arch. Aid. Health, 17,118 (1958). 108. P. Rossine. Arch Cewerbepathol Cewerbehyg. igne, I. Holroquist, Acta Derm- VenereoL Stockh. 51, Suppl. 26 (1951). R. M. Watrous and M. B. McCaughey, Ind. Med., 14,639 (1945). A. Heyman et al., JV. EngL J. Med., 254,401 (1956). In D. V. Frost, Fed. Proc., 26,194 (1967). E. D. Osborne, Arch. Derm. Syph., 12,773 (1925). 115. S. S. Pinto and C. M. McGill, Aid. Med., 22,281 (1953). 116. R. A. Kyle and G. L. Pease, AT. EngL J. Med., 273,18 (1965). 117. H. S. DucolT, et al., Proc. Exp. BioL Med., 9,548 (1948). 118. K. Morgareidge, "Inorganic vs Organic As Metabolism," Food and Drug Research Labs.. Inc Maspexh, N.Y., 1963. 119. E. J. Coulson et al., / Hutr., 10,255 (1935). 120. L. R. Overby and D. V. Frost, ToxicoL AppL Pharm., 4,38 (1962). 121. H. H. Schrenk and L. Schrribeia, Am. Ind. Hyg. Assoc. J., 19,225 (1958). 122. L. J. Goldwater, WHO Chronicle, 21(5), 191 (1967). 123. A. Hill and E. L. Failing, Brit. J. Ind. Med., 5,2 (1948). * 124. In B. L. Vallce et al.. Arch. Ind. Health, 21,132 (I960). 125. E. G. Young and F. A. H. Rice, /. Lab. C/m. Med., 29,439 (1944). 126. G. W. Monier-Williams, Trace Elements in Food, Wiley, New York, 1949, pp. 162-206. 127. K. Thoma et al.. Arch. Exp. Pathol. Pharmacol., 226,255 (1955). 128. P. Ehrlich, Ber. Dtsch. Chem. Get., 42, Part I, 17 (1909). 129. C. Voegtlin, et al., U.S. Public Health Rep., 58,1882 (1923). 130! E. S. Guzman-Barron and T. P. Singer, Science. 97,356 (1943). 131. R. A. Peters and R. W. Wakdin, Biochem. J., 40, 513 (1946). 132. L. C. Gunsalua./ Cell. Comp. Physiol., 41,Suppl. 1,113 (1953). 133. D. V. Frost, Feedstuffs, 48(52), 19 (Dec. 20,1976). THE MET; `r1 * - r* I, 'V * It- * k , r-. "* ' y ,,a ^- -3 * 44* i .* - :.N. iv % 134. V. M 135. W. G 136. D. V. 137. R.J. < 138. C. Bar 139. W. C. 140. A. He' 141. J. a. present 142. P. E. I 143. S. S. P 144. F. Rot) 145. A. M. 146. A. C. I 1974. 147. J. A. > Cjnlere 148. I. J the com 149. M G. C 150. N. C. N 151. "NIOSl Criteria 152. S. Toku. 153. H. W. f 154. C. A. Na 155. R. A. Wi! 156. D. Macav 157. F. M. Bu` 158. W.J. Me. 159. H. B. Ell 160. A. Hamtl 161. S. S. Pint 162. C.J.Jose 163. S. F. Due 164- H. B. Elk 165. Air Poilu. ington, D 4 BARIUM, 4.1 Source Barite, atu Arkansas, C; AB.0001126706 NGER on the below .e as a -1975." as., Inc.. t THE METALS 1531 134. V. M. Goldschmidt. Geochemistry, A Muir, Ed., Oxford L'nivcrsity Press, 1954. p. 743. 135. W. G. Hoekstra. Fed. Proc., 34,2083 (1975). 136. D. V. Frost, Fcedsluffs, 48(14), 55 (Apr. 5, 1976). 137. R. J. Shamberger et al.. ,-trcA. Environ. Health, 31, 231 (19~6). 138. C. Baroni, C. J. van Esch, and U. SafTiotti, Arch. Environ. Health. 7,668 (1963). 139. W. C. Hueper and W. W. Payne. Arch. Environ. Health, 5,445 (1962). 140. A. Hevman et al.. Seu Engl. J. Med.. 254,401 1956. 141. J. A. Newman et al.. `'Bronchogenic Carcinoma in the Copper Smelting and Mining Industry," presented at Conference on Occupational Carcinogenesis. New York. March 24-27, 1957. 142. P. E. Enterline, report to K. W. Nelson, Asarco, New York. June 2. 1975. 143. S. S. Pinto and B. M. Bennett, Arch. Environ. Health, 7, 583 (1963). 144. F. Roth, Virchows Arch. {Pathol. Anat.) Physiol. Klin. Med.. 331,119 (1958). 145. A. M. Lee and J. F. Fraumeni, J. Satl. Cancer Inst., 42, 1045 (1969). 146. A. C. Rencher and Nl. W. Carter, unpublished report to Kennecott Copper Corp., New York, Apr. 4, 1974. 147. J. A. Newman et al.. "Bronchogenic Carcinoma in the Smelting and Mining Industry," presented at Conference on Occupational Carcinogenesis, New York. March 24-27, 1975. 148. A. M. Baetjer et al., "Analysis of Mortality Experience of Allied Chem. Plant," unpublished report to the company, July 16, 1974. 149. M. G. Ott et al.. Arch. Environ. Health, 29,250 (1974). 150. N. C. Nelson, et al.,/. Chron. Dis., 26,105 (1973). 151. "NIOSH Criteria for a Recommended Standard Occupational Exposure to Inorganic .Arsenic__New Criteria--1975." 152. S. Tokudome and M. Kuratsune, Inti. J. Cancer, 17,310 (I9'6). 153. H. \V. Hake, Lancet, 2, 220 (1910). 154. C. A. Nau, South Med. /., 41,341 (1948). 155. R. A. Wills, Ind. Med., 17, 208 (1948). 156. D. Nlacaway and D. A. Stanley, Brit. /. Ind. Med., 13,21*7 (1936). 157. F. M. Bulmer et al., /. Ind. Hyg., 22,111 (1940). 138. W.J. McKinttry and J. M. Hicks, Arch. Ind. Health, 16,32 (195**). 159. H. B. Elkins and J. P. Fahy, Ind. Med. Surg. 36,747 (1967). 160. A. Hamilton and H. L. Hardy, Industrial Toxicology, Hoeber. New York, 1974, pp. 132-135. 161. S. S. Pinto et al.. Arch. Ind. Hyg. 1, 437 (1950). 162. C. J. Joscphson etal.. Arch. Ind. Hyg., 4,43 (1951). 163. S. F. Dudley./. Ind. Hyg., 1, 215 (1919). 164. H. B. Elkins, Chemistry of Industrial Toxicology, Wiley. New York, 1939, p. 64. 165. Air Pollution Aspects of Odorous Compounds, National Air Pollution Control Administration, Wash ington. D.C., 1969. 4 BARIUM, Ba 4.1 Sources and Production (1) Barite, natural barium sulfate (BaS04), occurs in the United States in Alaska, riArkansas, California, Georgia, Missouri, Nevada, and Tennessee, and in Canada and .Xh' * VAB i 4 A * CINCINNATI, OHIO AMERICAN CONFERENCE OF GOVERNMENTAL INDUSTRIAL HYGENISTS INC. VAB.0001126708 * 1 ARSINE AsHj TLV, 0.05 ppm (02 mg/m3) Arsine is a cotoriess gas with a disagreeable garlic odor. It has a molecular weight of 77.93, specific gravity of 2.695, melting point of -173.5* C, boiling point of -55 C, a vapor pressure of > 1 atmosphere and decomposes at 230 C ft is soluble in water, slightly soluble in alcohol and alkalies. It is used in organic synthesis; as a military poison gas; doping agent for solid state electronic compounds. Most cases of arsine poisoning do not result from the manufacture or use of the gas itself; rather they come from formation of arsine as a byproduct of a chemical reaction involving, in most instances, a base metal, an arsenic im purity, and an acid, or, rarely, a strong alkali. The extreme acute toxicity of arsine is well known; 250 ppm for 30 minutes is fatal, and 3 to 10 ppm can cause poisoning symptoms in a few hours.*1* Nau<3 found that animals exposed three hours a day to concentrations bet ween 0.5 and 2 ppm developed blood changes in a few weeks. Published reports of occupational and other poisoning from arsine describe some 310 cases, 74 of them fatal, through 1959.*3* Several reports since 1960 record 28 cases, with two deaths, in this country*4*7* and abroad.***10* Typical cases resulted in hemoglobinuria, jaundice and hemolytic anemia. * } While data on the actual concentrations causing acute intoxication are lacking, post event concentrations of 70 to 300 ppm (Morse and Settertind, fatal cases,*11* 5 ppm Kip ling and Fothergill*** and 0.5 ppm Elkins*3* were reported. When urine samples were analyzed at early stages concen trations of arsenic ranging from 0.5 to 2 mg/l were the rule, but occasionally much higher values were found. Bulmer et ai*12* reported a number of cases of chronic poisoning, with severe anemia. Urinary arsenic levels aver aged 2.3 mg/L, dropping to 0.66 mg/L three days later. Creig et a/*13* recorded three relatively mild chronic cases with arsenic in urine levels of 0.5 mg/L In an extensive clinical study of 14 simultaneous cases of arsine poisoning,*14* tissue arsenic levels, determined by neutron activation analysis, indicated a total body content of arsenic one-third to one-half the lethal dose (300 mg), one "assumes" that the poisoning action of the hydride follows to some extent that of the trioxide, none of the cases were fatal, but ranged from mild to very severe. He molysis and renal damage typified the toxic responses. The most severely poisoned had oliguria for 40 days and re quired hemodialysis 10 times, but hemolysis disappeared in a few days in all others. In four cases, renal function was impaired for a long time, but was finally restored. Since arsenic appears to be excreted rather freely in the urine,*1** the levels found in the urine of intoxicated work ers could have resulted from inhalations of concentrations below 1 mg/m3 or 0.25 ppm. The recommended TLV of 0.05 ppm (0.2 mg/m3) is the same as that of other inorganic arsenic compounds, which are considered substantially less toxic. Other recommendations; Cook (1945) 1 ppm; Smyth (1956) and Elkins (1959) 0.05 ppm; USSR (1966) 0.1 ppm; Czechoslovakia (1969) 0.06 ppm. References: 1. Henderson, Y, Haggard, H.W.: Noxious Cases, Reinhold, NIY (1943). 2. Naia, GAj South. Med. f. 47:341 (1948). 3. Elkins, HA: Chemistry of Industrial Toxicology, p. 64, Wiley & Sons, NY (1959). 4. Konsen, J.L, Dodson, VJN* J. Occup. Med. ft540 (1966). 5. Elkins, H.&, Fahy, tnd. Med. ft Surg. 36:747 (1967). 6. Teftelhaunt, D.T,, Kicr, LCa Arch. Env. Health 79:133 (1969). 7. DePalma, AJL: /. Occup. Med. 77:582 (1969). 8. Kipling, M.D,, Fothergill, IL: Brit J. tnd. Med., 27:74 (1964). 9. Kambara, Tv Nohara, Y,, Ikegama, 1C, Nakamura, T,, Kajiwara, T.: /. Sci. Labour 42:454, japan (1966). KL Fallentin, ft* Frost,J,, Grot, A~ Ugeskrift for Laeger 729544 (1967). 11. Morse, KAL, Setterlind, A.M: Arch. tnd. Hyg. ft Occup. Med. 2:148 (1950). 12. Bulmer, FA4JL, Rothwelt, HI, Polack, S3, Stewart, D.W.: /. Ind. Hyg ft Tox. 22:111 (1940). 13. Creig, H.B.W,, Bradlow, BA, Harrison, C, Dalton, MA: 5o. Af. Med. J. 32.101 (1958). 14. Arsine Poisoning in a Metal-Refining Piant, B. Nielson, ed., Acta Med. Scand. Suppl. 15. Elkin* H.8.: Am. Ind. Hyg Assoc. J. 28:305 (1967). ASBESTOS For the purpose of considering a recommendation for a threshold value of asbestos dust in the workplace, only the TLV, Appendix Ala-- Recognized Carcinogen second definition above is applicable. Although there are four types of natural mineral fibers that have been in in 0.5 fiber > 5 pm/cc -- Amosite dustrial use, only three have been used in the United 10 fibers > 5 jim/cc -- Chrysotile States: chrysotile, amosite, and crocidolite. The fourth, an- 0.2 fiber > 5 pm/cc -- Crocidolite 10 fibers > 5 jim/cc -- Other forms thophyllite, is mined and used in Finland. Of the three types of asbestos that have been used in North America, Canadian chrysotile has formed 95% of all natural mineral fibers used, with amosite and crocidolite (both imported \ According to recent authoritative mineralogical defini from South Africa) constituting the other 5%. It should be / tions,TM asbestos is "1) A collective mineralogical term en noted that chrysotile is classified as a serpentine mineral, compassing the asbestiform varieties of various minerals; 2) whereas the other three types of asbestos are amphiboles. An industrial product obtained by mining and processing primarily asbestiform minerals." It is now generally recognized that excessive inhalation of asbestos dust causes chronic inflammations of lung tis- VAB.0001126309 HYDROGEN SELENIDE HjSe TIV, OjOS ppm ( mg/m*), as Sc Hydrogen selenide is a colorless gas with a molecular weight of 60.96 and a specific gravity of 2.12. It has a boil ing point of -41.5* C and liquifies at 0*C under a pressure of 6.6 atm. It has a disagreeable odor resembling decaying horseradish, however, it can cause olfactory fatigue and the odor is therefore not reliable as a warning of dangerous levels. Hydrogen selenide is irritating to the eyes and mu cous membranes. It is soluble in carbon disulfide, carbonyl chloride and 377 ml H^Se/lOO mL water at 4* C Hydrogen selenide is readily produced by the action of acids on inorganic selenides. It can also be formed by the reaction of selenium with organic matter and by the direct combination of the elements.*11 Cooper and Glover*1* classify hydrogen selenide as one of the most toxic and irritating selenium compounds. Dudley and Miller*2* reported that single eight-hour ex posures of guinea pigs to 1.0 mg/m1 (0.3 ppm) of hydrogen selenide resulted in the death of 50% of the animals. In humans a concentration of 5.0 mg/m1 (1.5 ppm) was found to be intolerable due to eye and nasal irritation while IX) . mg/m1 (0.3 ppm) caused no irritation with exposure of a few minutes duration. They recommended that any con centration of hydrogen selenide which could be detected by odor should be avoided as being "potentially danger- ous". This would reportedly be a level well below 1.0 mg/m1. " Buchan*1* reported five cases of industrial selenosis in laboratory workers due to less than 0.2 ppm of hydrogen selenide. Predominating symptoms were nausea, vomi' metallic taste in the mouth, alliaceous breath odor, extreme lassitude and fatigue. Gloved4* adds running nose and eyes, cough, sneeze, slight tightness of the chest, and ultimately, pulmonary edema to the symptoms caused by hydrogen selenide. In a treatise on the toxicology of selenium, Glover*4* states that "hydrogen selenide has never caused a death or an illness lasting more than ten days in a human being" The two reasons given for this are, first, that hydrogen sel enide is never used in quantity and, second, that hydrogen selenide is rendered to the less toxic red selenium by oxi dation on the mucous membranes of the respiratory sys tem. A TIV of 0.05 ppm is recommended to prevent irritation and maintain the current record of preventing the onset of chronic hydrogen selenide related disease. Swedish limit (1978) 0.01 ppm. References: 1. Cooper, C.W,, Glover, JJL: in Zkigaro and Cooper's Selenium, Van Nostrand Itemhoid Go., NY (1940). 2. DucRey, H.C, MMer, J.W.: JL Ind. Hyg. 8k Tots. 21:470 (1941). 1 Buchan, IFj Occup. Med. 439 (1947). A Glover, JJL: Ind. Med. Surg. 39:50 (1970). HYDROGEN SULFIDE H]S TIV, 10 ppm ( w 14 mg/m*) STEL, 15 ppm ( 21 mg/m*) Hydrogen sulfide is a colorless gas with an offensive odor suggesting rotten eggs. It has a molecular weight of 34.08 and a density of 1.19 (air-1.00). It boils at -60l2* C and freezes at -83.8* C Hydrogen sulfide is flammable with explosive limits by volume in air of 43 and 46%. At O* C, 437 cc of HiS will dissolve in 100 mL of water; at 40* C 180 cc. Hydrogen sulfide has been widely employed as a reag ent in analytical chemistry, and is used in the manufactur of heavy water. It is a source of elemental sulfur. The ma jority of occupational exposures to H2$, however, have re sulted from its occurrence in petroleum, natural gas, soil, sewer gas, and as a byproduct of chemical reactions, such as may take place in the viscose rayon and certain leather tanning processes. In high concentrations (500-1000 ppm) hydrogen sulfide acts primarily as a systemic poison, causing uncon sciousness and death through respiratory paralysis.*1* A case of polyneuritis and encephalopathy from one day's exposure to a concentration insufficient to cause loss of consciousness has been reported.*2* In lower concentra tions (50-500 ppm) hydrogen sulfide acts primarily as a re- spiratory irritant. It is reported that pulmonary edeme and bronchial pneumonia may follow prolonged exposure at concentrations of the order of 250-600 ppm.*1* At low con centrations the effects on the eye predominate, with con junctivitis the most common effect, while keratitis fre quently occurs.*4-5* Poda,*N however, in summarizing the effects of 174 exposures to H2S in a heavy water plant, stat ed that eye irritation was relatively uncommon. More com mon findings were nervousness, cough, nausea, headache and insomnia. The reported LCjo, one hour inhalation ex posure, for rats was 713 ppm and 673 ppm for mice.*7* - The concentrations at which eye effects occur have been variously reported as 100 ppm,*** 30 ppm,<voi 20 ppm,*11* IS ppm,*1* above 10 ppm,n* 10 ppm, or even 5 ppm*14* 4-15 ppm.*1s> In view of the fact that five different sources reported eye effects at 20 ppm or below, a TIV less than this level would seem to be indicated. In addition, the experience of three members of the TLV Committee |4) tends to confirm the reports that conjunctivitis may result from exposures at 20 ppm. The limit of 10 ppm corresponds to the working level of 10 ppm used in a heavy water plant, according to Poda.*7* In its criteria document*1** NIOSH quoted two addition al references*171** in which eye effects from H2$ at conr-ntrat ions of 20 ppm or less were reported. It also comn ed that exposure at low concentrations for a few hours has been associated with headache, sleep disturbances, nau sea, weight loss and other signs and symptoms suggestive VAB.0001126'&$ ratory diseases (as estimated by having a measured normal alphatrypsin inhibitory factor in blood).*1*) Some industrial operations using phosgene follow a "work practice" procedure wherein an attempt is made, using engineering techniques to preclude exposure to phosgene. Under this practice, detection of any level of phosgene is considered as evidence that a condition for potential exposure has occurred. Anyone suspected of being exposed under these circumstances to any level is medically evaluated and treated if required. Personnel are trained to recognize the odor of phosgene (odor detection limit is considered to be 0.5 ppm) and report any effluvi um.*17) The National Academy of Sciences lists a 90 day atmos pheric limit for use in submarines of 0.05 ppm and a Doug las aircraft continuous atmospheric limit of 0.04 ppm.o> Because of its irritating effect on the respiratory tract at levels slightly above Oil ppm, but from which tolerance deve lopes, a TLV of 0.1 ppm is recommended. Other recommendations: Belgium, Holland, Romania, Sweden and Switzerland, 0.0S ppm. Most other countries, including the USSR, as well as the Council of Europe, have adopted the 0.1 ppm or its mg/m3 equivalent. References: 1. Cross, P., Rinehart, WX, Hatch, T~ Arch. Env. Health 70.768775 (1965). 2. Cameron, GA, Courtke, F.G, Foss, G.L, Short, LH.D* Calder, RSamford, L, Fairley, A* Watkmston, CX, Williams, LT.Ou First Report on Phosgene Poisoning, Proton Report 2349, Part II, UNCLASSIFIED Report, Ministry of Defense, UK (April 1942). 3. IbkL: Part VII. . 4. Cordier, D,, Conger, &: Compt. Rend. Soc. Biol. 747:327-530 (1952). 5. Ibid.: /. Physiol. 45:421-428 (1953). 6. Box, G.E.P., BuUumbine, H-* Brit. J. Pharm. 2:38 (1947). 7. Henschler, D,, Laux, Naunyn-Schmied. Arch. Exp. Path, u Pharmak. 329.433 (1960). 8. Stokinger, HX: Proceedings 13th International Congress on Occupational Health, New York Gty (1960). 9. Stokinger, HX, Wagner, W.D., Dobrogorskl, OX: Arch. Ind. Health 76:514 (1957). 10. CWS Field Lab. Memo 1-4-5, p. 30S, UNCLASSIFIED Report, Medical Div. Status Summaries (1944). 11. Chasis, H4 Phosgene, Review of the Literature on the Effect of Exposure to Man and Experimental Animals, Contract W49-036-CWS-1 (1944). 12. Freeman, &, Grodins, FX, Kosman, A.|4 Fasciculus on Chemi cal Warfare Medicine, Vol. II, Respiratory Tract, Chap. XX, Temperature & Humidity in the Treatment of Phosgene Poi soning, UNCLASSIFIED Report, Committee on Treatment of Gas Casualties, National Research Council (1945). 13. Merck Index, 9th ed., p. 955, Merck & Co., Inc., Rahway, N| (1976). 14. Cucinefl, 5a Arch. Env. Health 2A270-275 (1974). 15. Caldston, M, tuetscher, IX tongcope, W.T,, Sattkh, NL: /. Oin. Invest. 2&169-181 (1947). Ik Stokinger, HX, Mountain, LTV Scheet, LD.: Atm. N.Y. Acad. Sci. 757:968-976 (1968). 17. Verbal communication to Committee member from industrial representative (january 1974). 18. Report of the Panel on Air Standards of Manned Space Flight, Space Science Board, National Academy of Sciences 36 (1968). PHOSPHINE PH, TLV, 03 ppm ( m 0A mg/m3) STEL, 1 ppm (1 mg/m3) Phosphine is a colorless gas with a disagreeable, garliclike odor. It has a molecular weight of 34 and a density of 1.529L The boiling point is -85* C and the melting point is -133.5* C It is slightly soluble in water, soluble in alcohol and ether. With an autoignition temperature of 100* F (38* C), it rgn/tes readily at room temperature when other hydrides of phosphorus are present as impurities. Phos phine is formed by the action of moisture on metallic phosphides, or of caustic on elemental phosphorus, and may be present where these substances are handled or stored. The chief use of phosphine is as a fumigant; it is also a doping agent for electronic components, and used in chemical synthesis. Muller*1) found that phosphine concentrations of 5 ppm could be tolerated by laboratory animals for two months of 4-hour daily exposures, but fatalities resulted after seven similar exposures at 10 ppm. Waritz and Brown*21 found the four-hour LC for rats to be 11 ppm. Repeated 4-hour exposures at 4 ppm slightly reduced weight gain, which returned to normal after 12 days (9 four-hour exposures). The effects of le thal concentrations were typical of respiratory Irritation. According to Harger and Spolyar,*31 59 cases of phos phine poisoning, including 26 deaths, were recorded be tween 1900 and 1958. They reported the death of an acet ylene generator operator from pulmonary edema. The probable cause was phosphine, which was found after the event in concentrations of the order of 8 ppm, al though exposure was only one or two hours per day. Jones et aA4* noted symptoms such as diarrhea, nausea and vomiting, tightness of chest and cough, headache and dizziness in a number of workers exposed intermittently at concentrations up to 35 ppm, but averaging below 10 ppm in most cases. There were no cumulative effects. These au thors considered the TLV of 0.05 ppm unnecessarily low, and largely on the basis of this work the limit was changed to 0.3 ppm. This value does not take into consideration the possibil ity of chronic phosphorus poisoning, from phosphine, which has been stated by several authorities**-10) to result from prolonged exposure, although no such cases have been documented in the modem literature. It is recommended that the TLV for phosphine be 03 ppm and the STEL be 1 ppm. Other recommendations: Cook (1945) 1 ppm; Smyth (1956) 0.05 ppm; Elkins (1959) 0.1 ppm; USSR (1967), * VAB.0001126711 Czechoslovakia (1969) 0.07 ppm; Sweden (1978) 0.3 ppm; West Germany (1978) 0.1 ppm. References: 1. Mutter, W.: Arch. Exptl. Pith. Pharmakol. 795:184 (1940). 2. Waritz, R.S-, Brown, ILMj Am. Ind. Hyg. Assoc. J. 36:452 (1975). 3. Hargtr, P.N, Spotyar, LWj Arch. tnd. Health 18:497 (1958). 4. (ones, A.T,, lone*, R.G, Longley, LO. Unpublished report. New South Wales, Div. Occup. Health (1%2). 5. (idem: Am. tnd. Hyg. Assoc. /. 25:376 (1964). 6. Henderson, Y,, Haggard, H.W.: Noxious Gases, 2nd ed., p. 242, Reinhold, NY (1943). 7. FairhaN, LT^ Industrial Toxicology, 2nd ed., p. 91, Williams & Wilkins, Baltimore, MO (1957). 8. Johnstone, R.T., Miller, S4E.: Occupational Diseases and In dustrial Medicine, p. 141, Saunders, Philadelphia, PA (1960). 9. Patty, FAa Industrial Hygiene & Toxicology, 2nd ed., Vol. II, p. 883, Imerscience, NY (1963). 10. Am Ind. Hyg. Assoc.: Hygienic Guide Series--Phosphine (June 1964). PHOSPHORIC ACID h,po4 TLV, 1 mg/m* $TEl,3 mg/m> Phosphoric acid is a colorless, odorless, non-combusti ble solid with a molecular weight of 96 and a specific gravi ty of 1.834 at 18* C It melts at 42.35* C and has a vapor pressure of0.03 mm Hg at 20* C It is very soluble in water. When heated to 213* C, it converted to pyrophosphoric acid (H4P3O7). Phosphoric acid is of tremendous industrial importance, being used in fertilizers, detergents, foods and beverages, water treatment, pickling and rustproofing metals and for many other purposes. 6 The recommended threshold limit is based by analogy from comparable experience and data for sulfuric acid. Fumes of phosphorus pentoxide at concentrations ranging from 0.8 to 5.4 mg/m* were noticeable, but not uncomfort able, and concentrations between 3.6 and 11.3 mg/m* caused coughing among the inexperienced, but could be tolerated. Concentrations of 100 mg/m* were unendurable, except to hardened workers.n> The TLV of 1 mg/m* is ac cordingly below the concentration that causes throat irrita tion among unacclimated workers and well below that which is well tolerated by acclimated workers. According to the AIHA Hygiene Guide.ni phosphoric acid is less hazardous than nitric or sulfuric acid. A maximum concentration of 1 mg/m* as a TLV, with 3 mg/m* STEL are recommended. Other recommendations: Sweden (1978) 1 mg/m*; USSR (1976, PaO*) 1 mg/m*. References: 1. Rushing, OJL: Written communication to TLV Committee member (April 1957). 2. Am. Ind. Hyg Assoc: Hygienic Guide Series (1957). PHOSPHORUS (YELLOW) White phosphorus Ps TLV, 0.1 mg/m* STEW 03 mg/m* Phosphorus is a white to yellow, soft, waxy, crystalline solid which darkens on exposure to light. The molecular weight is 123.83, specific gravity is 1.83 with a vapor pres sure of 0.026 mm Hg at 20* C It has a melting point of 44* C and a boiling point of 280* G In moist air it ignites spontaneously at 30* C One gram is soluble in 400 ml ab solute alcohol, 35 ml benzene and 0.0003% soluble in 100 g water at 20* C It is used in gas analysis and in the manufacture of rat poisoning, fireworks and fertilizers. Yellow or white phosphorus is one of the most highly toxic inorganic substances, death reportedly resulting from a single dose of 1 mg/kg.d> Severe toxic symptoms in man have been reported following a single dose of 15 mg.<*> Inhalation of more than 20 ppm phosphorus vapors by rats (7 hrs/d, 5 d/wk) resulted in severe respiratory irritation and in high mortality rate due primarily to edema of lungs 338 and bronchopneumonia with hyaline membrane formation suggesting the action of inhaled actd.(*> Growth curves of animals exposed to 13-16 ppm/phos phorus (7 hrs/d, 5 d/wk for 4 months) were the same as controls.*** Prolonged exposure of the animals produced bone changes uncomplicated by severe kidney or liver damage.ro Fleming et afro found that rats injected with 0.05 mg/kg of yellow phosphorus per day eventually developed bone changes. This was the lowest dose tested therefore a zero effect dose was not attained. An increased death rate resulted from a doseage of 0.8 mg/kg/d. Buchanan et afn found that subcutaneous injection of 03-0.4 mg/kg/d to dogs resulted in death within a few days. Chronic poison ing, with liver damage, resulted from repeated doses of 0.1 mg/kg/d. if P** by animals* showed a distribution pati bone ^ liver > kidney. The level in soft J rapidly when exposure was stopped, but 1 bone was slow. Skin and hair also absorbed e amount of P; results were compatible inistered by inhalation or ingestion. f 0.1 mg/m* is probably sufficiently low to poisoning, but may not provide a wide marom undesirable effects. Phosphorus necrosis ave been reported among workers in the fireworks industries.***11! Dental and medical VAB.0001126712 HYGIENIC GUIDE SERIES & <C*M 4 A AltOCiMiOH Arsine (Hydrogen Arsenide, Arseniuretted Hydrogen) AsH, . (Revised 1965) Significant Physical Properties Arsine is a colorless gas with a slight garlic-like odor. Molecular weight: 7 7.93 Boiling point: -55 C Specific gravity of gas: 2.7 (air = 1) Solubility: 20 volumes/100 volumes of water (20C) Fire hazard: Practically nonflammable At 25C and 760 mm Hg: 1 ppm = 0.0032 mg/liter 1 mg/liter = 313 ppm I. Hygienic Standards A. Recommended maximal atmospheric concentrations (8 hours) i 0.05 parts of vapor per million parts of air by The Committee wishes to acknowledge the preparation of the medical information section of this Guide by the Indus* trial Hygiene and Clinical Tonicology Committee oi l.M.A- volume (ppm).1 This is based on both human experience and animal data.3*3 B. Short exposure tolerance: One to ten parts per million for an hour is probably dangerous.3*4 C. Atmospheric concentration immedi- VAB.0001126713 ately hazardous to life: Uncertain, but probably greater than 70 ppm.3 II. Toxic Properties A. Inhalation: Both chronic and acute exposures to arsine are dangerous. Chronic exposure to low* concentrations (less than 0.5 ppm may cause jaundice and hemolvtic anemia. With acute exposures. the symptoms are delayed. The first indication of arsine intoxication is the passage of dark red urine usually four to six hours after the exposure fol lowed by abdominal or back pain and anuria. Although the primary effect is the destruction of red blood cells, pulmonarv edema is encountered from severe exposures.3'*,t,,** The mechan ism of arsine poisoning has been studied and reported by Pemis and Magistretti.10 Based on their experiments per formed with erv4 throcv* tes. a close correlation was shown to exist between the fall of glutathione-SH (GSH) and hemolytic action of AsH3. It is impor tant to note that a certain amount of GSH is necessary to maintain the erythrocyte structure ir.tact. They con cluded that the hemolytic activity of arsine is due to its ability* to reduce the erythrocyte GSH. B. Eye contact: Few observations have been made of the local effects of arsine on the eyes probably because systemic injury occurs long before eyes would be injured. Even in fatal cases of arsine poisoning, no irritation of the eyes or respiratory tract was reported.11 III. Industrial Hygiene Practice A. Industrial uses: None. * B. Occurrences: Arsine mav occur in p metal pickling operations when the metal contains arsenic, as a result of certain metal dressing operations, as an impurity in acetylene and as a result of exposing any inorganic arsenic com- July-August, 1965 pound or solution to nascent hydrogen, C. Evaluation of exposures: 1. Air sampling and analysis: (a' Direct field methods: Detector tubes15 are available commer cially for making rapid, on-thespot surveys. However, these devices should be used only after a full knowledge of their >cnsitivitv and limitations is es- tabl ished. (b' Laboratory methods: Semiquantitative determination of arsine in air may be made using mercuric bromide test papers:3 by the Gutzeit Method,13 after collecting the gas in water in an all-glass device; by the method of Jacobs and Nagler14 or bv the ACGIH Method.1* m Unless routine analyses for * trace amounts of arsenic are made, the Gutzeit Method is not recommended. Many vari ables affect the results and necessitate the preparation of a separate standard curve for each group of samples.1* 2. Sampling and analysis of biological materials: Urinary levels above 0.5 mg of arsenic per liter in individuals exposed to arsine may be indicative of harmful exposure. In the case of single exposures even lower levels might be significant, but dietary fac tors must be ruled out before signifi cance is attached to any increase in the arsenic content of urine. Biological samples can be digested with a mixture of nitric-sulfuricperchloric acids without the need of reflux and determined bv the silver diethyldithiocarbamate or by the iodine microtitration.17 A molvbdenum blue method has been used in the past.1*1* D. Hazards and their recommended J h fy-A ugu <t, 1965 control: The atmospheric concentra tion of arsine in the workroom must be maintained below 0.05 ppm through the use of process enclosures and or adequate ventilation. Metal dross con taining arsenic must be kept dry. Respiratory protective equipment should not be employed as a routine control measure but rather to supple ment control procedures during emer gency situations. A self-contained breathing apparatus approved by the U. S. Bureau of Mines is recommended for emergency use. The universal gas mask will provide respiratory protection against low concentrations of arsine. IV. Medical Information A. Emergency treatment: Persons suf fering from overexposure should be re moved immediately from contaminated atmosphere, placed in bed and provided with medical care promptly. Those known to have been exposed to high concentrations of arsine should be hospitalked immediately. Both sympto matic and supportive therapy should be used as in other types of acute hemo lytic anemia. B. Special procedures: The hemoglobi nuria is a reversible phenomenon once exposure has ceased. Kidney damage is delayed by several hours to a few days depending on the dose received. Red cell destruction gives rise to increased potassium levels in the extracellular spaces. Therefore, treatment is directed at the potassium intoxication by using ex change resins and peritoneal dialysis. Fluid intake should be restricted to equal fluid output. Alkali may be needed to combat acidosis. If serum potassium is not elevated, dialysis should be reserved for use when the blood urea nitrogen (BUN) is over 100 mg <?c. BAL (dimercaprol 2,3-dimercaptopropanol) is not effective in arsine poisoning. However, 2,3-dimercapto- propyl ethyl ether and certain dithiols are reported to be capable of prevent ing the hemolytic action of arsine and affording significant protection in ex perimental animals if administered shortly after exposure.10 Dimcrcaptopropyl ethvl ether is not readily avail able. Earlv exchange transfusion has t U? been recommended although there have been no reports of its utilization in human intoxication.3' V. References 1. American Conference of Governmental Industrial Hygienists: Threshold Limit Values for 1964. .4 AfA Arch. Environ. Hralth 9: 545 ' 19641. 2. Committee on Threshold Limit Values: Do c u men tat ion of Threshold Limit Values. American Conference of Gov ernmental Industrial Hygienists. 1014 Broadway. Cincinnati 2, Ohio (1962). 3. Elkins. H. B.: The Chemistry of Indus trial Toxicology. 2nd Ed., p. 63, John Wilev & Sons. Inc.. New York City '* 4. Kipling. M. D., and R. Fothergill: Arsine Poisoning in a Slag-Washing Plant. Brit. J. 2nd. Med. 21: 74 (1964). 5. Patty. F. A.. D. W. Fassett, and D. D. Irish: Industrial Hygiene and Toxi cology. 2nd Ed., p. 878. Interscience Publishers. Inc.. New York Citv (19631. 6. Sollmann. T.: A Manual of Pharmaeology. 8th Ed., p. 1205, W. B. Saun ders Company. Philadelphia (1957). 7. Macaulay. D. B., and S. D. Austen: Arsine Poisoning. Brit. /. Ind. Med. 13: 217 (1956). 8. Lasch, F.: Clinic and Therapy in Se vere Arsenic Hydride Poisoning. Med. Klin. (Munich 1 53: 787 (1958). 9. Pavlova, O. N., and L. M. Mirochnik: Acute Arsine Poisoning. Gos. Izd. Med Lit. Uz. SSR: 103 (1962). 10. Pemis. B.. and M. Magistretti: Meek anism of Acute Hemolytic Anemia Pr* duced bv Arsine. Med. Lavoro 51: : (I960 11. Grant, W. M.: Toxicology of the 7, 0001126715 n p. 56, Charles C Thomas Publishers, Springfield, Illinois (1962). 12. Kobayashi, Y.: Rapid Method for the Determination of Low Concentrations of Arsine by Detector Tube. Kogyo Kagaku Zasshi 59: 899 (1956). 13. Snell, F. D., and C. T. Snell: Colon.metric Methods of Analysis. D. VanNostrand Co., Inc., New York Citv (1949). 14. Jacobs, M. B., and J. Nagler: Colori metric Microdetermination of Arsenic. Ind. Eng. Chem., Anal. Ed. 14: 442 (1942). 15. Monkman, J. L.: Determination of Arsenic in Air. Analytical Methods Manual. American Conference of Gov ernmental Industrial Hygienists, 1014 Broadway, Cincinnati 2, Ohio (1956). 16. Dubois, L., and J. L. Monkman: Deter mination of Arsenic in Air and Bio July-August, 1965 logical Materials. Amer. hid. Hyg. Assoc. J. 22: 292 (1961). 17. Monkman, J. L., and L. Dubois: Ar senic Digestion Losses in the Prepara tion of Biological Samples. Amer. Ind. Hyg. Assoc. J. 23: 327 (1962). 18. Sandell, . B.: Colorimetric Determi nation of Traces of Metals. 2nd Ed., p. 176, Interscience Publishers, Inc., New York City (1950). 19. Schrenk, H. H., and L. Schreibeis. Jr.: Urinary Arsenic Levels as an Index of Industrial Exposure. Amer. Ind. Hyg. Assoc. J. 19: 225 (1958). 20. Kensler, C. J., J. C. Abels, and C. P. Rhoads: Arsine Poisoning, Mode of Action and Treatment. J. Pharmacol. Exper. Therap. 88: 99 (1946). 21. Goodman, L. S.. and A. Gilman: The Pharmacological Basis of Therapeutics. 2nd Ed., p. 937, Macmillan Co., New York City (1955). t l t i T wmm J li i + .) * I j)aB.00011^716 of BIOLOGICAL DATA Edited By WILLIAM S. SPECTOR Prepared under the Direction of the Committee on the Handbook of Biological Data DIVISION OF BIOLOGY AND AGRICULTURE THE NATIONAL ACADEMY OF SCIENCES THE NATIONAL RESEARCH COUNCIL W. B. SAUNDERS COMPANY ________ __ ^ Philadelphia and London VAB.0001126717 I 4 r t' i 240. LUNG VENTILATION: VEATEBAATES ViImi, wIim othcrwiM noted. ivtrtfti of manna for tht raotlng aiatt. Rm|m tn porentAonon r* aaitmata "<f of ttio tn r-, (ef Introdoc Species Respiration Frequency bresth/min 1 1 Tidal Volume1 ml Minutr V .'lvlfll* I- 1 Premature 2 Newborn, aaleep 3 Adult y 49 5 Cat (Petis calus) 4 Cow (Dos taurus) 7 Oog Goat 9 Guinea pig (Cavia cobaya) 10 Hamster (Meaocricctus auratux) 11 Horse (Cquua caballu*)4 12 Manatee* Florida (Trichechus lati roetrie) 13 Marmot (Marmots marmots) 14 Monkey (Mac sca mulatto) 13 Mouse (Mui muoculus) 14 Porpoise (Tureiopa t runeatus) 17 Rabbit (Lepus cuniculus) 1 Rat (Rattus norvegicus) 19 Rat* cotton (Sigma dsn hispadual 20 Sloth (Choleopus boffmatui) 21 Sloth (Bradypus grioeus) 22 Turtle (Msleclemys centrats) 3) 41(24-114) 11.7(10.1-13.1)3 11.7(10.4-1 1.0)* 2S 11(27-40) 15(11-10) 19.0 90(49-104) 74(11-127) 11.9(10.4*13.4) T.0<4.0-5.0) 5.0* 40(31-52) 143(04-230) 1.1(0.9*1.3) 31(34-40) 94(73-115) 11.0 (4.3*0.0) 3.7 12.415.4-17.3) 14.7(10.0-27) 740(757.094)* 1)4(254- )4))7 12-4 2530(2200-3*00) 320(231-4)2) 310 I.O(l.O-).O) 0.01(0.42-1.2) 9000(4 520-9400) (5000-9000) 22.0 * 21(9.0-21) 0.15(0.09-0.23) 9.000(5.000-10.0001 21(19.3-24.4) 1.5(1.4-1.4) 0.35(0.24-0.70) 14.0 0.41(0.20-0.Ml 0.72(0.43-1.411 7.4(5.0-10.))' 4.5(4.0-7.01* 0.32 4(59*104) 5.2(3.3-7.41 5.7 0.14(0.09-0- 3*| 0.034(0.024-0.05 *1 107 45(35-40) 0.17>2 0.04(0.31-1.41) 0.023(0.011-0.04,) 9.7(9.0-10.4) 1.07(0.50-1.141 0.100(0.07 3-0.10> 0.04(0.02 3-0.071) 0.04(0.00-1.0) 0.49(0.33-0.71) UdM rowo (Of nv)H **m )< Vt|VlfE/ * tul WIHIHV* f *f Rf Light work. 1T.I|15.7-1.2); heavy work. 2I :(I0,4*23.J>. rkc 14T0(I510-1770); heavy work. 2030(1900*2lit). /5/ RttUflf. Light work, 29(27*11); heavy work* 40(50*0). f4/ Rest* if, Light work. 19; heavy work, 30(25-31). /7/ Resting. Ufhl work, 040(0 H-MS); heavy work, 000(490-1270). // Resting. Ught work. ing, 0.009. htivy ork 14,$|17.J-JI,0|. /$/ Pertheron* gelding. /10/ Hibernating, 0.40. /II/ Hibernating* 13(11.5-15,0). >12/ Hibernat 249. PULMONARY VALUES. EQUATIONS. DEFINITIONS: MAN Port !: LUNG AIR VOLUME. RECUMBENT Part II: INT RAPULMONIC Velvet are from tmoothttf curves plotted from mean values, (INTRA-ORAL) PRESSURE and are for the following conditions: J7C, ambient pressure, Values are for males snip* Mean lung vol* saturated with water vapsr. Ranges in parentheses are from umes are given as per cent of vital capacity* smoothed curves of ranges, and are estimate "if* of the 93% Ranges in parentheses are estimate "I" of 1Introduction Ago I Total Lung Capacity Vital Capacity* yr_______ 1 L ___ _______ L Volume r3*TM-------------------- mm Hg SlX 9 29 I I 1| it.4(1.3-3.1)* 1.210.9* I t.2 (0.9* I.T)^ 3 Ten f 49 12.5(2.2-3.1) 12.5(2.2- 3,1)3 1.9(1..*2.4) 1.9(1.4*2.4)3 5 Fourteen f 4t 14.4(3.5-4.1) |).4|2.5-4.3)2 3.70.0-4.7) 2.7<2.2-1.5)3 7 Eighteen f 0t ls.9(4.3-0.0) 14.1(3.1-5.3)3 4. 4(4.0-9.9) 1.012.4-4.2)3 9 Twenty f 10 9 14.3(4.3-5.3) 14.2(3.1-5.3)3 4.9(4.0-4.0) 1.0 (2.4-4.4)J 11 Twenty-five d |4.4(4. J-9.0) 12 4.2(3.1-5.4) 4.90.3-4.0) 3.00.2-4.2)1 13 Thirty-five d 14 9 15 Forty-five d J4.1 (4.3-5.5) |4.3(3.0-5.4) 3.9(4.3-l.0) 4.50.3-4.0) 3.00.0-3.0) 4.30.0-5.1) 14 9 17 Fifty* five f 10 9 19 Sixty-five d 20 9 4.3(2.9-5.7) 3.0(4.3-g.O) 4.2(2.5-3.71 5.4(4.3-7.0) 3.9(2.5-5.5)3 2.90.0-S.7) 4.10.4-5.9) 2.70.4-3.5) 1.70.5-5.0) 2.30.4-1.4)3 21 Seventy-five d 5.2(4.3-7.01 22 9 J 3.912.5-5.0)3 3.30.5-4.5) volume air contained In lungs after deepest possible inspiration. Total lung capacity minus vital Maximum Expiratory Pressure 7 42(14.7*40} 2 25.0 52(10.9-94) 3 44 70(30-109) 4 40 90(47-133) $ 75 93(30-120) 4 03 107(74-144) 7 too 120(04-1431 Maximum In sin raiory Preeuure T3--^ li'fiT-lllJl 9 21.7 75(44-103)* 10 35 43(24-1011* 11 54 57(24-00)1 12 74 45(14.0-7))* 13 91 24(2.2-491* Relax atton Pressure 14 0 -l9.2(-32 to -4.4) 15 13.9 14 31 -5.3(-t).3 to -1.5) -l.3(-9-9 to 7.3) 17 51 4.1 (-1.9 (o 10.14 10 72 10*5(1.9 lo 19,1) 19 e? 14.9(0.) to 29.3) 20 100 20.4(10.2 t* 31) capacity equals residual capacity or residual sir, /2/ Vol ume of air expired in deepest possible expiration following /!/ Negative pressure. deepest possible inepiration, /!/ Values are estimates; a sex difference may exist. Part ID: INTRAPLEURAL PRESSURE Values are cm IfaO relative to aimoeghertc pressure ration Expiration 2 Deep breathing -30 lto-5 3 Miller's1 -30 to 40 54 Valsalva*** Normal* 40 -O.Tf-0.3 to -1.0) 0.4(0- 1,0) 4 Labored* -l.M-O.S to -1.3) 2.4(1,0 to 3.0) 7 Normal4 -1.3M.0 to -1.5) 2.4(1.0 to 3.3) Infants* end of inspiration -3 7? End of exsirslion ] Inspiration with glotus closed* fZf Expiration with glottis closed. /!/ Air pressure at posterior pharynx. /4/ Air pres sure si trachsal bifurcation* : 3 V.PREDICTION EQUATIONS A r the following condlti t ambient pmo vapor, MBCumoxtn capacity. iq m: Vpulmonary VCwltal capacity. 1 i^aftij, <i week, reeung V 0.139 0.00107 ir* 2 to-17 rr VC 0.0542 H 0.0097 AW 4.27 3 140*100 cm 4 i 40-190 cm VC 0.0492 N * 9,02 VC 0.0799 H - 9.79 5 Males, standing 4 remales, standing 7 Males VC 0.025 H* VC * 0.020 K* MIC * 154.3 - (0.542 i All SA> Females MBC (71.3 - (0.474 i Alt 1 *A> 9 Both sexes MBC M 1 (1.24 - 0.0099 A)* Hi V eight in ouncea. /i/ Age 14%; over 75 yr *10%. /!/ Values laboratory methods* 1 24T * VAB.0001126718 A DRAFT * "WORLD BANK AND IFC GUIDELINES FOR IDENTIFYING, ANALYZING AND CONTROLLING MAJOR HAZARD INSTALLATIONS IN DEVELOPING COUNTRIES** February 1985 Office of Environmental and Scientific Affairs Projects Policy Department WORLD BANK Washington, D.C. ft VAB.0001126719 # * -1DRAFT December 1984 4 A WORLD BASK and 1FC GUIDELINES FOR IDENTIFYING, ANALYZING, AND CONTROLLING MAJOR HAZARD INSTALLATIONS IN DEVELOPING COUNTRIES Preamble The European Economic Community have taken a lead In developing guidelines controlling major accident hazards of certain Industrial activities. The Environmental Council of the Economic Community met on June 24, 1982 and adopted such a directive .which member states were required to comply with by January 8,~ 1984. Inpetus was given to the European Community to consider the need to control major hazards by. In particular, four serious Industrial accidents; the Fllxborough explosion In 1974 killed 28 workers, injured 89 people and caused widespread damage to housing In the vicinity of the plant; the disaster at Beek in Holland in 1975, an explosion and fire killed 14 people o.n site following the release *m of propylene at the refinery. The two other cases were at Seveso and Manfredonla In Italy In 1976, where highly toxic substances were released contaminating the surrounding districts, and raising Implications regarding the health of people exposed to the toxic Recently the explosion of natural gas in Mexico City killing some 450 people and the toxic gas release at Bhopal in India killing more than 2,500 people has highlighted the urgent need for the World Bank to adopt similar guidelines to those developed by the EEC. These latter two incidents Illustrate the even greater risks that must be controlled in installations producing hazardous substances in developing countries. VAB.0001126720 i. ** 1 -1- TABLE OF CONTENTS Page Wo* A 1.0 Introduction. ........... ............................ ..................................2 tt 2 0 Potential Industrial Hazards................................... .................... .2 3.0 Identification System for Major Hazards............................4 3.1 Introduction..................................................................... 4 3.2 Threshold Quantitiesfor Notification.... ... .................... 6 3.3 Quantities Requiring Full Safety CaseStudy..7 4.0 Implementation of the Guidelines................................................. 7 4.1 Requirements for Notifiable Installations..................... 8 4.1.1 4.1.2 4.1.3 Identification of Major Accident Hazards..8 Steps to Prevent Major Accidents and to 8 Limit Their Consequence..................................8 Steps to Provide Information, Training, and Equipment for Persons Working On Site.................................................................... ....9 4.2 Requirements for the Full Safety Case............................ 9 4.2.1 4.2.2 4.2.3 Objectives.......................... .......................................... 10 The Content of the Full SafetyCase.................. 10 Information to be Included in A Full Safety Case................................................................. 11 4.2.3.4 It stances Listed in Appendix III..11 iJ Management System for Controlling the Activity........12 Information Relating to the Potential Major Accidents.......13 5.0 Emergency Plans.................................................................................... .. 5.1 On-Site Emergency Plans............... .15 5.2 Off-Site Emergency Plan........................................................... 15 6.0 Restrictions on Development in the Vicinity of Major Hazard Installations......................................... 16 Bibliography.............................................................................................. 17 Appendix I................................................................. Appendix II............................................................................................................... Appendix III................................................................ 24 Appendix IV........................................................................................ I 33 * VAB.0001126721 -2- 1.0 Introduction 1. These guidelines are based substantially on the EEC directive on the major accident hazards o certain Industrial actlvl ties and regulations promulgated under the United Kingdom Health and Safety at Work Act. 2. Industrial activities Involving certain dangerous subs- itial to give rise to serious Injury or damage d the Immediate vicinity < These activities commonly come to be known Hazards These guidelines are concerned with the protection of the health and safety of persons In the workplace and persons outside the plant boundary, as well as the protection of the environment. Furthermore, they apply generally to Industrial processes, storage and transport of hazardous material, but do not apply to nuclear or to extraction or mining operations or to licensed hazardous waste disposal sites. According to the guide lines, persons In control of activities involving certain dangerous, explosive, flammable and toxic substances must demonstrate that major accident hazards have been recognized, and that measures have been mini consequences of those that do occur. 3. It Is the object of these guidelines to provide a frame work In which a developer can supply evidence and justification for the safe operation of the proposed Industrial activity. It Is not the objective of these guidelines to provide details or specific methods of analysis, safe operating procedures, etc. which are the contents of a Major Hazard and Risk Assessment Manual currently in preparation by the World Bank. 4. In summary, those guidelines identify two distinct levels of analysis and control of a hazardous industrial activity. The first lower level of control classifies an installation handling certain varying quantities of dangerous materials a "Notifiable Installation" At the highest level of control an installation is classified as a "Full Safety Case" In between these two cases will be installations requiring a progressively increasing level of analysis and control. * 2.0 Potential Industrial Hazards 5. Although 'major hazard (or major accident)' is defined in the guidelines and Includes the phrase 'a major emission, fire or explosion', the definition uses a mi interpreted. An occurrence will be a maj following conditions. (a) that It leads to a serious danger to people or the environment: A I VAB.0001126722 (b) that it results from uncontrolled developments la the course of an 'Industrial activity'; and w (c) that it Involves one or more 'dangerous substances' 6* 'Serious danger to persons' should be taken to mean death or serious Injury including to healthy or the threat of death or serious injury, whether caused immediately by the accident (e.g., col lapse of a populated building caused by an explosion) or as a delayed effect (e.g., pulmonary oedema following some hours after exposure to a toxic gas), and affecting or potentially affecting people inside and outside the installation. It is emphasized that the accidents, actual or potential, should be major ones distinguished from other serious accidents not only by the severity of the casualties but by the numbers of them, or by the physical extent of the damage. 7. The reference to delayed effects is not Intended to include the cumulative effects of frequent exposure to small amounts of the dangerous substance and, therefore, brief excursions slightly above the routine control limits for toxic substances should not be considered as major accidents. 8. 'Serious danger to the environment* should be taken to mean a significant, relatively long-lasting (but not necessarily irre versible) effect on plants or animals on land. In the air or In the water which has the potential to lead to a serious danger to man. For example, serious pollution by a toxic substance of a water course used for drinking water could pose a threat to man. 9. 'Uncontrolled developments' should be taken to mean that the occurrences of concern are likely to develop quickly; to be outside the normally expected range of operating problems; to present only limited opportunity for preventive action; and to require any such action to be in the nature of an emergency response. It also serves to indicate that the guidelines are concerned with acute rather than chronic events, i.e., uncovenanted or unusual rather than covenanted or regular releases of the dangerous substance. Similarly, 'a major emission' refers to a relatively large, sudden and unconvenanted release of the dangerous substance from its normal containment. 10. It is clearly possible to identify, using a pragmatic approach, the Installations and activities that pose the main threat of a major accident. It is also relatively easy to decide whether an event was a major accident after it has occurred. It is much less easy to define 'major accident' for the purpose of making predictions, as the developer is required to do in his safety analysis as an essential step in demonstrating the adequacy of the measures taken to prevent such accidents. The following examples outline events which may be taken, prlna facie, as major accidents: VAB.0001126723 (a) any major firm giving rise to thermal radiation at the site or plant boundary exceeding 5 kv/m^ for several seconds; (b) any release actual or, potential, of a hazardous subs* tance where the total quantity released is a signifi cant proportion of the quantity which invokes the guidelines, e*g*, releases of kilogram quantities of Group A. toxic substances; ton quantities of other toxic substances; ton quantities of pressurized or refrigerated flammable gases; or tens of tons of flam* mable liquid; (c) any vapour or gas explosion which could give rise to blast overpressures at the site or plant boundary exceeding 0.5 bar; and/or (d) any explosion of a reactive or explosive substance which could cause damage to buildings or plant outside the immediate vicinity sufficient to render them or it inoperative for weeks* 11. These estimates should include all the quantities of each substance present whether it is in pure form or part of a mixture* However, the substances should be in a form capable of giving rise to major accident hazards, e.g., no account should be taken of ammonia unless it is anhydrous or is in water solution containing more than 50Z by weight, nor should account be taken of stored chlorinated potable water* 3.0 Identification System for Major Hazards 3.1 Introduction 12* The proposed system for identifying major hazards is based on the quantity (or inventory) of hazardous substance stored or pro* cessed at an industrial site or in transit* In this context the term "Installation' is used to describe the general activity which may result in a major accident hazard The term "installation" is defined further in Appendix I* 13* A two level system is used to identify potential major hazard installations. The first is defined as the threshold quantity of hazardous substance above which It is necessary for the developer to notify the World Bank of a potential major hazard (see Section 3.2). The second level is defined as the quantity of hazardous subs* tance above which it is necessary for the developer to undertake a full safety case assessment (see Section 3.3). VAB.0001126724 I 5 14* The quantities specified in Sections 3.2 and 3.3 relate to the total quantity of substance held on site. A developer nay be involved in an activity in which the quantity of a hazardous substance varies over a period, due either to seasonal demand, or because the site is complex and Includes a number of processes each of which has an inventory which varies froa day to day or even hour to hour. In such cases the manufacturer should aaka an estimate of the quantity of each substance liable to be on site and a decision as to whether the .... ri requirements of Sections 4, 5, and 6, apply should be based on the maximum anticipated quantity. 15. The estimation of the quantity of a substance at a site should include all the amounts which are likely to be on the site under the control of the same manufacturer. In the case of production and process activities, this will Include quantltltes in manufacture, use or processing, and associated storage (l*e., the storage that is used in connection with the process). Account should also be taken of any quantities In pipelines on the site and In Internal transport ope rations. These estimates should Include all quantities of any dange rous substance whether the substance is in pure form or part of a mix ture or present as a by-product. For example. If a chemical plant manufactures a hazardous substance, the estimate of the total quantity should take account of the quantities which are present in reaction mixtures and purification processes together with the quantities which are present In storage. In certain processes there may be circums tances where a significant quantity of a dangerous substance can only be produced if abnormal conditions develop in the plant. If such an event can reasonably be predicted, then this should be taken into account-in estimating the overall quantity of the substance on a site. An example of this type of situation was the production of a signifi cant quantity of tCDD (dioxin) when conditions of excess temperature and pressure developed In a plant producing 2,4,5-trlchlorophenol at 16. It should be noted that when estimating the quantity of hazardous substance to assess whether the site becomes subject to these requirements, it is necessary to add the quantity of substance In process to the quantity In associated storage together with any amounts of the same substance in any installation within 500 metres owned by the same manufacturer. If the nearby Installation is more than 500 metres away then it is only necessary to add the quantities if these are such that there could be. In foreseeable circumstances, an aggravation of the major accident hazard. It is realized that In some cases interpretation of this 500 meter requirement might be dif ficult but reasons for inclusion or exclusion should be clearly spec! fled. 17. Although an industrial activity involves, or is liable to involve, hazardous substances, this does not of itself make the acti vity subject to these World Bank guidelines. The hazardous substance 4 VAB.0001126725 mist be present under circumstances which could give rise to a major accident* Thus* It may be possible for a developer to argue that a major accident cannot, in fact, arise* It may be that the physical state of a substance or the way in which It is distributed round the site may avoid the possibility of some types of accidents* This may be particularly relevant to many of the toxic substances which are involatlle liquids or solids* These may not have the potential to cause a major accident unless some special factor, such as energy contained In a pressurized system, is present, although spillage Into water courses may still remain a problem. 3*2 Threshold Quantities for Notification 18* A list of hazardous substances at quantities above which the World Bank must be notified Is presented in Appendix II* This Appendix is divided into four sections, namely: (A) Very toxic substances; (B) Other toxic substances; (C) Highly reactive substances and explosives; and (D) Flammable substances* 19* The criteria for the two groups of toxic substances, name ly groups (A) and (B) of the Schedule are gl7en In terms of the toxic effects on populations of specified experimental animals, though in two cases in addition to fulfilling these criteria the substances must have physical and chemical properties capable of entailing major acci dent hazards* This is taken to mean that the properties are such that the toxic substance could be easily distributed throughout the envi ronment if containment is breached, for example, a gas or highly vola tile liquid or a solid which might be ejected from a pressurized A substance has to satisfy only one of the three criteria for ingestion, percutaneous (i.e*, through the skin) or Inhalation toxicity In the tables to qualify. In the case of Class (A) subs tances indicative criteria are provided and the World Bank should be Informed if any such substance is or could be Involved, irrespective of the quantity* 20* In the case of Class (B) toxic substances quantities have been specified for some of the more common substances* However, for those unnamed substances which fall into the indicative criteria given in Appendix II, quantities exceeding 1 ton should be notified* 21* Notification also is required for any process using plant at a pressure greater than 50 bars when the product of the volume of , *the pressure system in cubic meters and the pressure in bars exceeds 10 000 * VAB.0001126726 3.3 Quantities Requiring Full Safety Case Study 22. A list of hazardous substances, at quantities above which a full safety case study is required is presented in Appendix III. It consists of a list of hazardous substances divided into four groups: toxic substances in quantities of one ton or less, toxic substances in quantities of greater than one ton, highly reactive and explosive substances and flammable substances, and gives quantity thresholds for the purposes of Section 4.2. 23. There are a large number of toxic substances in Appendix III ranging from dioxin at 1 kg to sulphur dioxide at 1000 tons. Many of the substances are pesticides and a typical example Is warfarin at 100 kg. The group of highly reactive substances includes materials such as peroxides and ethylene oxide. Typical explosive substances listed are nitrate esters such as nitroglycerine and trialtroaromatic compounds such as trinitrotoluene (TNT). 24. Most of the entries in the Schedule refer Co a specific hazardous substance by a chemical name such as hydrogen cyanide or hydrogen sulphide but some entries are in the form of a generic defi nition. Typical generic definitions used are salts, powders and com pounds, and examples of these are the entry for beryllium (which Includes powders and compounds) and the entry for arsenic pentoxide (which Includes arsenic (V) acid and salts). In other cases the entry in Appendix III refers to a particular concentration of a solution of a hazardous substance such as formaldehyde. Nitrocellulose has an entry in Appendix III which is qualified by the nitrogen content. 25. Hazardous substances in Appendix III are only affected by requirements of Section 4.2 if they are in a state capable of present ing a major accident hazard. For example, nickel powder or cobalt naphthenate stored in drums would not be expected to present a major accident hazard. 4.0 Implementation of the guidelines 26. The guidelines require that proof of safe operation be available at any time. Developers must show that they have identified the major accident hazards arising from their activities and have taken adequate steps to prevent such major accidents in design, lay out and siting will provide adequate steps to prevent such major acci dents during operations and will provide people on site with the information, training and equipment to ensure their safety. 27. The activities which are covered fall into one of two categories. The first is wide ranging and covers any industrial process using a substance which is either toxic, flammable or explo sive in quantities greater or equal to those given in Appendix II threshold quantities (i.e., a notifiable installation). The second i VAB.0001126727 f *I * -8 includes activities involving substances in quantities greater or equal to those in Appendix III (l.e., installations requiring a full safety case study). 4.1 Requirements for Notifiable Installations \ < 28. A developer who has control of a "notifiable installation" to which this guideline applies shall at any time provide evidence including documents to show that he has: (a) identified the major accident hazards; and has (b) taken adequate steps to: i (i) prevent such major accidents and to limit their consequences to persons and the environment; and (11) provide persons working on the site with the Information, training and equipment necessary to ensure their safety* 4.1.1 Identification of Major Accident Hazards 29. The evidence should identify the dangerous substance and the approximate quantity present on the site; l.e, where the substance is held and in what state; and should show the main ways In which it could be released from its normal containment in sufficient quantities and in such a manner as to create a major accident. Guidance on the definition of major accident is given In Section 2. If it Is judged that the Industrial activity is not capable of creating a major acci dent, the reasons should be clear from the evidence. 4.1.2 Ste Prevent or Accidents and Limit Their Consequence 30. The evidence should include an outline of the primary preventive measures (proper design, construction, inspection, maintenance and operation of storage vessels and process plant); any special measures which prevent potentially hazardous excursions from normal operating conditions from proceeding to a major accident (e.g. alarms, trips, dump tanks, scrubbers, etc.); and measures aimed at an Incipient major accident to limit its consequences (e.g. water cur tains, emergency procedures, etc.). The preventive measures should be linked to the appropriate major accident hazards already identified in the evidence. It is not necessary to specify the preventive measures in detail. For example, it will be sufficient to record that storage and process vessels are designed to the appropriate Standard, or Code of Practice, rather than to list each vessel and the particular stan dard to which it was designed. The important fact is that the ready availability of the evidence demonstrates the commitment of the developer to safe operation. VAB.0001126728 4.1*3 Steps to Provide Information, Training and Equipment for Persons Worklag on Site 31. The developer Is required by these guidelines to provide his employees end certain others working on his site with the informa tion, training and equipment necessary to ensure their safety* The evidence should refer to the arrangements made to ensure that the necessary information, training and equipment for major accidents are given to persons working on site* As with the evidence on preventive measures, it Is not necessary to specify precisely what the relevant information, training and equipment is, but Instead the evidence should show the steps taken to ensure that: (a) persons working on the site have been informed of the major accident hazards of the activity and have been Informed of and received training about the relevant emergency procedures; (b) operators with particular responsibility for the activities that present a major accident hazard have been trained to a level appropriate to those responsibilities; and (c) any special equipment necessary for use in an emergency (e*g*, breathing apparatus, or fire fighting equipment provided to ensure the integrity of a means of escape has been provided)* 32* The detail of the presentation will depend on specific circumstances, for example, the potential extent of hazardous impact, the location, population density, meteorology, topography, as well as special local circumstances* 4.2 Requirements for the Full Safety Case 33* For major hazard installations handling dangerous materials in excess of the quantities listed in Appendix III a "full safety case** study is required* A full safety case study must show that the activity will be carried on safely; it includes a description of the major accident hazards that could arise from a manufacturer's activities and the controls that are exercised to prevent them or to limit their consequences* 'Hajor accident' is defined in Section 2 and guidance is given on the definition in this section* The guidance that follows discusses some of the general issues that bear on the full safety case. There also may be instances when it will be necessary to carry out a full safety case study for quantities of dan gerous materials less than those listed in Appendix III, as possibly indicated by the* preliminary assessment study carried out under Section 4.1* < i k VAB.0001126729 10 4.2.1 Objectives The objectives of the full safety case are: (a) to identify the nature and scale of the use of dange rous substances at the installation; (b) to give an account of the arrangements for safe opera* tlon of the installation, for control of serious deviations that could lead to a major accident and for emergency procedures at the site; (c) to identify the type, relative likelihood, and broad consequences of major accidents that might occur; and (d) to demonstrate that the developer has appreciated the lajor hazard potential of the company's activities and has considered whether the controls are adequate.. 35. In addition, the work that the developer does in preparing his safety case study should enable him to provide the competent authority responsible for making emergency plans outside the installation with an estimate of the scale and consequences of the realization of the hazards, in accordance with the requirements of these guidelines (seeSectlon 5). 4.2.2 The Content of the Full Safety Case 36. The full safety case is essentially an abstract of rele vant information about the major hazard aspects of the activities from a much more extensive body of information. This body of information will Include plant design specifications, operating documents, mainte nance procedures, and information derived from the examination of the major hazard potential by means of techniques such as hazard surveys, hazard and operability studies, hazard analysis and risk assessment. (Details of these techniques will be given in a forthcoming World Bank Manual) 37. The information required in the safety case falls into two broad categories: first, factual information about the site, its activities and surroundings, and second, the core of the safety casereasoned arguments and judgments about the nature, likelihood and scale of potential major accidents which may occur at the Installation and the means to prevent these hazards being realized. 38. It is not possible to specify precisely what the second part of the full safety case should contain because the complexity of the potential hazards will vary greatly from site to site; indeed, any such specification would be too elaborate for many installations because it would need to cover the most complex cases. Thus, the Pi 4 VAB.0001126730 J1 11 requirements below ere In broad terms, allowing a flexible approach by firms to the discursive and judgmental, as distinct from the factual part of the full safety case* The essence of the full safety case, and the reason behind the choice of that term, is that the onus lies on the developer to assess his own hazards, take measures to control them adequately, and then to present his conclusions* 39* The full safety case should, therefore, contain sufficient Information about the major accident potential of the developers acti vities to enable judgment to be made whether the significant risks have been Identified and are being properly managed* In some Instan ces It may be necessary to ask for Information In the full safety case to be supplemented by further Information, but Ideally the aim should be to provide a safety case which stands on Its own as a demonstration that major accident hazards are being adequately controlled* AO* The full safety case should provide adequate justification for its conclusions, either by setting out the sources of the evidence for a particular argument, or by recording the principal assumptions in sufficient detail to enable them to be challenged If it emerges that they are critical to the conclusions of the safety case* For example, a full safety case may state that the Integrity of pressure vessels has been assured by the strict application of appropriate design codes, operating duties, maintenance and inspection procedures. In support of an assumption that the sudden failure of pressure ves sels has been dismissed as a possible cause of a major accident* A safety case may also perhaps say that the risk of an aircraft crashing on the Installation is insignificant In comparison with other causes of a major accident, because the site Is well separated fom the near est airport and air traffic lanes* Clearly, the amount of evidence required on each aspect of the safety case will vary according to the importance of that aspect and In particular the consequences of the particular accident being considered* 4*2*3 Information to be Included in a Full Safety Case 41 The report shall contain the following 4.2.3.1. -------- ----------------------------------------- "* " (1) The name of the substance as given In Appendix III or for substances Included in Appendix III under a general designation the name corresponding to the chemical formula of the substance; (11) A general description of the analytical methods available to the developer for determining the presence of the substance, or references to such methods in the scientific literature; VAB.0001126731 12 (ill) 4..brief description of the hazards from the subst ance; * (iv) In cases where the substance may be Isolated from process vessels, its percentage concentration! and the main impurities and their percentages. 4.2.3.2 Information relating to the installation? (1) A map of the site and its surrounding area to a scale large enough to show any features that may be significant in the assessment of the hazard or risk, associated with the site; (11) A scale plan of the site showing the locations and quantities of all significant inventories of the hazardous substances; (ill) A description of the processes or storage involving the hazardous substance and an indication of the conditions under which it is normally held; i # (lv) The maximum number of persons likely to be present on site; and (v) Information about the nature of the land use and the size and distribution of the population in the vicinity of the activity to which the safety case relates. 4.2.3.3 Information relating to the management system for controlling the activity: (1) The staffing arrangements for controlling the acti vity with the name(s) of the person(s), and if appropriate his (their) deputies or the competent body responsible for safety and authorized to set emergency procedures in motion and to inform out side authorities; (11) The arrangements made to ensure that the pro vided for the safe operation of the activity are properly designed, constructed, tested, operated and maintained; (ill) The arrangements for training of persons working on the site. VAB.0001126732 (1) A description of the potential sources of a major accident and the conditions or events which could be significant In bringing one about; (11) A diagram of any plant or plants In which the acti vities are carried on sufficient to show the features which are significant as regards the potential for a major accident or Its prevention or control; (111) A description of the measures taken to prevent, control or minimize the consequences of any major accident; * (iv) Information about the emergency procedures laid down for dealing with a major accident occurlog at ' the site; (v) Information about prevailing meteorological condl tions In the vicinity of the site; and (vl) An estimate of the number of people on site who may be particularly exposed to the hazards considered In the written report* Further details on these items are given in Appendix IV, while a flow chart (Figure 1) summarizes the procedures outlined above In Sections 4*1 and 4*2* 4 ' VAB.0001126733 14 Figure 1: Procedures for Safety Analysis and Control Major Hasard Installation A * HAVE I A SUBSTANCE LISTED IN APPENDIX II OR III? IS ANT SUBSTANCE PRESENT AT OR ABOVE THE THRESHOLD QUANTITY IN APPENDIX II? YES 11 --mJ NO ACTION PREPARE .EVIDENCE OF SAFE DESIGN AND OPERATION, INCLUDING: 1. IDENTIFICATION OF MAJOR ACCIDENT HAZARDS; 2. PREVENTATIVE MEASURES EMPLOYED; 3. EMERGENCY PROCEDURES TO BE ADOPTED; AND 4. SAFETY MANAGEMENT. SEE SECTION 4.1 IS ANY SUBSTANCE PRESENT AT OR ABOVE THE QUANTITY REQUIRING A FULL SAFETY CASE IN APPENDIX III? YES PREPARE A FULL SAFETY CASE AS DETAILED IN SECTION 4.2 NO FURTHER ACTION UNLESS BACK-UP INFORMATION REQUIRED BY THE SPONSORS REVIEW BY W.B. * VAB.0001126734 15 5.0 Emergency Plan* 42. The guidelines require developers to prepare an adequate emergency plan for dealing with major accidents that may occur on their sites. 5.1 On-Site Emergency Plans 43. it Is not the Intention of these guidance notes to explain In detail how to prepare an on-site emergency plan. The detail and scope of the emergency plan will vary according to the complexity of the site and It Is, therefore, not appropriate to prescribe here pre cisely what the plan should cover. The developer will need to consi der the potential major accidents which will be Identified In the safety assessment (Section 4) to ensure that the plan takes account of them. Useful guidance in preparing the emergency plan may be found In the booklet 'Recommended Procedures for Handling Major Emergencies* published by the Chemical Industries Association. * 44. The developer should ensure that the on-slte emergency plan is compatible with the off-site emergency plan which should be drawn up by the local authority. The on-slte and off-site plans should be Interlocked to ensure that they provide a comprehensive and effective response to emergencies. 45. The plan should Include the name of the person responsible for safety on the site (usually the site or plant manager) and, if different, the name of the person who Is authorized to set the plan In action. 46. The developer should keep the on-slte emergency plan upto-date, and to ensure that It takes account of any changes In opera tions on the site that might have a significant effect on the plan. The developer is also required to make sure that people on the site who are affected by the plan are Informed of Its relevant provisions. This should Include not only those people who may have duties under the plan, but also those who may need to be evacuated from the site In an emergency. Including contractors and visitors. 5.2 Off-Site Emergency Plan 47. The Intention Is that emergency plans should be drawn up or amended by the local authority after consultation with bodies who might be able to contribute Information or advice. Such consultation Is seen as an Important aspect In the preparation of adequate emergen cy plans - this has been well demonstrated in the case of plans which are in operation in many areas of the world. Obviously the developer must be consulted about the major accident hazards and the possible consequences, and any special emergency measures. VAB.0001126735 16 A 48* A two-way flow of Information Is required between the developer and the local authority. Information from the developer Is needed to enable the authority to draw up the off-site emergency plan; Information from the authority should be available to the developer when he prepares the on-slte emergency plan. 6.0 Restrictions on Development In the Vicinity of Major Hazard Installations 49. The extent of the safety buffer zone or rest opment zone which should be specified for a major hazard may be determined using a non-site specific approach, or by-case basis. Regardless of the approach adopted, the great Import- maintaining a restricted development, safety buffer zone Is shown by the experience In Mexico and Bhopal In India, as well her hazardous Installations around the world. 50. A non-site specific approach to setting the limits of a safety buffer zone such as has been adopted in the UK and Europe may provide useful guidance for the full safety case. Using this approach two zones are established* at distances of 1 km and 1-2 km from the major hazard installation. Within 1 km no developments are allowed which Increases the population at risk (the safety case study deter mines if the existing land use In the safety buffer zone is acceptable or not at the planning stage of the major hazard Installation). Thus, the population at most risk can be controlled. In the 1-2 km zone only limited development is allowed involving a low density of popula tion (such as warehouses and light industry, etc.) and certainly no shanty towns, hospitals, schools, or high-rise developments are allowed 51. A "case-by-case" approach may be indicated for notifiable Installations that do not meet the full case study criteria. For these installations a broad risk assessment taking into account local factors, size and storage, process, management, etc. may Indicate that a smaller safety buffer zone is required. A procedure has been devel oped for estimating local community risk to aid In determining safety buffer zones for notifiable major hazard installation. Suitable pro cedures will be presented in detail in the forthcoming World Bank Manual on Hazard and Risk Assessment. VAB.0001126736 4 *i * A Biblio 1* European Community Directive, 1982* "On the Major Accident nazards of Certain Industrial Activities". 82/501/EEC. Official Journal of the European Community, L230, June 1982. 2. UK Health and Safety Commission. "Consultative Document: Control of Industrial Major Accident Hazards (Draft Regulations and Guidance)." Health and Safety Executive, November 1983* 3. UK Notification of Installations Handling Hazardous Substances Regulations, 1982. SI No. 1357 (and UK Health and Safety Executive Guide, Booklet HS(R) 16). 4. "A Guide to Hazard and Operability Studies". Chemical Industries Association, London, 1977. 5. "Recommended Procedures for Handling Major Emergencies", Chemical Industries Association, Alembic House, 93 Albert Embankment , London SE1 6. "Codes of Practice for Chemicals With Major Hazards; Chlorine", Chemical Industries Association, 1975. VAB.0001126737 r 18 - Appendix I 'i Definition of the Term "Installation" Installations for the production or processing of organic or Inorganic chemicals using for this purpose. In particular: - alkylation - amlnatlon by ammonolysls - carbonylatlon - condensation - dehydrogenation - esterification * - halogenation and manufacture of halogens - hydrogenation * - hydrolysis - oxidation 4 - polymerization - sulphonatlon " desulphurization, manufacture and transformation of sulphur-containing compounds * - nitration and manufacture of nitrogen-containing compounds * manufacture of phosphorus--containing, compounds " formulation of pesticides and of pharmaceutical products Installations for the processing or organic and inorganic chemical substances, using for this purpose, in particular: - distillation - extraction - solvation p A VAB.0001126738 - 19 -- nixing - drying 3* Installations for distillation, refining or other processing of petroleum or petroleum products* 4* Installations for the total or partial disposal of solid or liquid substances by incineration or chemical decomposition* h 5* Installations for the production or processing of energy gases, for example, LP6, LNG, SNG* 6* Installations for the dry distillation of coal or lignite* 7* Installations for the production of metals or non-metals by the wet process or by means of electrical energy* 8* III* Storage of dangerous materials Identified In Appendices II and 9* Transportation Distribution Systems :V - Pipelines (quantities between block valves) - Shipping and terminal facilities (Including In-land waterways) - Road - Rail 1/ There may be an overlap between these guidelines and many national and International regulations, and guidelines concerning transfer of hazardous substances* When a national or International regulation applies to a particular Installation, the World Bank guidelines should be used only as a check to ensure that all safety aspects have been Identified and controlled* VAB.0001126739 h 20 A List of Hazardous Substances Requiring Notification (A) "Very Toxic" Substances The following indicative criteria is used to identify any "very toxic" substance requiring notification* These criteria are Independent of the quantities of the substance stored, or processed, or oay be formed by an unwanted by-product reaction* Very toxic substances are defined as: substances which correspond to the first line of the table below; substances which correspond to the second line of the table below and which, owing to their physical and cheml cal properties, are capable of entailing major-accident hazards similar to those caused by the substance entloned In the first line: LD 50 (oral) (1) LD 50 (cutaneous) (2) LC 50 (3) /k* body weight /kg body weight /I (inhalalatlon 1 LD 50 <5 LD 50 <10 LC 50 <0.1 5<LD 50<25 10<LD 50<50 0.1<LC 50<0.5 Note: Note: Note: (1) LD 50 oral in rats* (2) LD 50 cutaneous in rats or rabbits* (3) LC 50 by inhalation (four hours) in rats* (B) Other Toxic Substances (1) The following quantities of toxic substances represent the threshold above which notification and compliance with the requirements of Section 4*1 are required* Named Substances m Notifiable Quantity Tonnes Phosgene Chlorine Hydrogen fluoride Sulphur trloxlde Acrylonitrile Hydrogen cyanide 2 10 10 15 20 20 VAB.0001126740 *  21 Carbon disulphide Sulphur dioxide Bromine Ammonia (anhydrous or as solution containing more than 502 by weight of ammonia) 20 20 40 100 (2) In addition to the above named substances the following Indicative criteria is used to identify other unnamed toxic substances which are stored or processed in quantities of greater than 1 tonne: LD 50 (oral) (1) mg/kg bodv weight 25 <LD 50 <200 LD 50 (cutaneous) (2) /kg body weleht <LD LC 50 (3) /l (lnhalalatlon <LC 50<2 Note: Note: Note: (1) LD 50 oral in rats* (2) LD 50 cutaneous in rats or rabbits* (3) LC 50 by inhalation (four hours) in rats* (C) Highly Reactive Substances (1) The following quantities of "highly reactive" substances represent the threshold above which notification and compliance with the requirements of Section 4*1 are required-* Named Substances Notifiable Quantity Tonnes Hydrogen Ethylene oxide Propylene oxide tert-Butyl peroxyacetate tert-Butyl peroxyisobutyrate tert-Butyl peroxymaleate tert-Butyl peroxy isopropyl carbonate Dlbenzyl peroxydlcarbonate 2,2-Bis(tert-butylperoxy) butane 1.1- Bis(ter-butylperoxy) cyclohexane Di-sec-butyl peroxydlcarbonate 2.2- Dihydroperoxypropane Dl-n-propyl peroxydlcarbonate Methyl ethyl ketone peroxide Sodium chlorate Liquid oxygen 2 5 5 5 5 5 5 5 5 5 5 5 5 5 25 500 4 VAB.0001126741 22 General Groups of Substances Notifiable Tonnes Organic peroxides (not listed above) Nitrocellulose compounds Ammonium nitrates 5 50 500 (2) In addition to the above named substances, the following indicative criteria Is used to identify potential explosive hazards. Irrespective of materials stored or processed* - Substances which may explode under the effect of flame or which are more sensitive to shocks or friction than dlnltrobenzene (D) Flammable Substances The following quantities of "flammable** substances represent the threshold, above which notification and compliance with the requirements of Section 4*1 are required* Class of Flammable Substances Notifiable Quantity Tonnes 1* Flammable Gases: Gas or any mixture of gases which Is flammable in air and is held as a sa 2* Liquefied Gases and Flammable Liquids in Process Pressure and/Temperature Above Ambient Levels: A substance or any mixture of substances which is flammable in air and is normally held in the Installation above its boiling point (measured at 1 bar absolute) as a liquid or as a mixture of liquid and gas at a pressure of more than 1*4 bar absolute* (e*g* LPG's)* 25 being the total quantity of substan ces above the boll* lng points whether held singly or in mixtures 3* Refrigerated Liquefied Gas A liquefied gas or any mixture of liquefied gases, which is flammable in air, has a boiling point of less than 0C (measured at 1 bar absolute) and is normally held In the installation under refrigeration or cooling at a pressure of 1.4 bar absolute or less (e.g*, LNG). 50 being the total quantity of subs* tances having boiling points below 0C whether held singly or in mixtures A VAB.0001126742 i4 4. Highly Flammable Liquids A liquid or any mixture of liquids not included in items 1 to 3 above, which ha8 a flash point of less than 21C. 10,000 VAB.0001126743 * 24 - A List and Quantities of Hazardous Substances Reaulrln: Full Safety Case The quantities set out below relate to each Installation or group of Installation belonging to the same deveoper/operator (where the distance between the Installation Is not sufficient to avoid) any aggravation of major accident hazards. These quantities apply In any case to each group of installations/activities belonging to the same developer/operator where the distance between the Installations is less than approximately 500 meters. Group As Very Toxic Substances (Quantity.< 1 Tonne) (See definition Appendix II, Page 20) Aldlcarb 4-Aminodiphenyl Amlton Anabaslne Arsenic pentoxlde, Arsenic (V) add and salts Arsenic trloxide, Arsenlous (III) add and salts Arsine (Arsenic hybride) Azinphos-ethyl Azinphos-methyl Benzidine Benzidine salts Beryllium (powders, compounds) Bis (2-chloroethyl) sulphide Bis (chloromethyl) ether Quantity for Application of Requirements Given in Section 4.2 " 100 kilograms 1 kilogram 1 kilogram 100 kilograms 500 kilograms 100 kilograms 10 kilograms 100 kilograms 100 kilograms 1 kilogram 1 kilogram 10 kilograms 1 kilogram 1 kilogram VAB.0001126744 - 25 - Carbofuran Carbophenothioo Chlorfenvinphos A-(Chioroformyl) morpholine Chloromethyl methyl ether Cobalt (powders, compounds) j Crimldine Cyanthoate Cydoheximlde Dane ton Diallfoe 00-Dlethyl S-ethylsulphinylmethyl phosphorotloate 00-Dlethyl S-ethylthlomethyl phosphorothloate 00-Dlethyl S-lsopropylthlomethyl phosphorodlthioate 00-Diethyl S-propylthlomethyl phosphorodlthioate Dime fox Dimethylcarbamoyl chloride Dlmethylnl trosamlne Dimethyl phosphoramldocyanldlc acid Dlphadnone Disulfoton EPN Ethlon Fensulfothlon 100 kilograms 100 kilograms 100 kilograms 1 kilogram 1 kilogram 100 kilograms 100 kilograms 100 kilograms 100 kilograms 100 kilograms 100 kilograms 100 kilograms 100 kilograms 100 kilograms 100 kilograms 100 kilograms 1 kilogram 1 kilogram 1 tonne 100 kilograms 100 kilograms 100 kilograms 100 kilograms 100 kilograms 7l VAB.0001126745 4 - 26 - Fluenetll Fluoroacetic acid 1 Fluoroacetic add* salts -p Fluoroacetic acid, esters Fluoroacetic acid, amides 4-Fluorobutyric acid 4-Fluorobutyrlc acid, salts 4-Fluorobutyrlc add, esters 4-Fluorobutyrlc acid, amides 4-Fluorocrotonic acid 4-Fluorocrotodc add, salts 4-Fluorocrotodc acid, esters 4--Fluorocrotodc add, amides 4-Fluoro-2-hydroxybutyric add 4-Fluoro-2-hydroxybutyric acid, salts 4-Fluoro-2-hydroxybutyric acid, esters 4-Fluoro-2-hydroxybutyric add, amlds Glycolodtrile (Hydroxyacetooltrlie) 1, 2, 3, 7, 8, 9-Hexachlorodibenzo-p-dioxin Hexame thylpho s phoramide Hydrogen selenlde Isobenzan Isodrin Juglone (5-Hyd roxynaphthalene-1,4-dlone) 4,4' - Hethylenebls (2-chloroaniline) 100 kilograms 1 kilogram 1 kilogram 1 kilogram 1 kilogram 1 kilogram 1 kilogram 1 kilogram 1 kilogram 1 kilogram 1 kilogram 1 kilogram 1 kilogram 1 kilogram 1 kilogram 1 kilogram 1 kilogram 100 kilograms 100 kilograms 1 kilogram 10 kilograms * 100 kilograms 100 kilograms 100 kilograms 10 kilograms A h + * VAB.0001126746 - 27 - Methyl Isocyanate Mevlnphos 2-Naphthylamine * Nickel (powders9 compounds) Nickel tetracarbonyl Oxydlsulfoton Oxygen difluoride Paraoxon (Diethyl 4-nitrophenyl phosphate) Parathlon Parathlon-methyl Pentaborane Phorate Phosacetlm Phosphamldon Phosphine (Hydrogen phosphide) Promurlt (l-(3,4-Dlchlorophenyl)3-trlazenethlocarboxamlde 1,3-Propanesultone l-Propen-2-chloro-l,3-diol dlacetate Pyrazoxon Selenium hexafluoride Sodium selenite Stlblne (Antimony hydride) Sulfotep Sulphur dlchlorlde s> Tellurium hexafluoride 1 tonne 100 kilograms 1 kilogram 100 kilograms 10 kilograms 100 kilograms 10 kilograms 100 kilograms 100 kilograms 100 kilograms 100 kilograms 100 kilograms 100 kilograms 100 kilograms 100 kilograms 100 kilograms 1 kilogram 10 kilograms 100 kilograms 10 kilograms 100 kilograms 100 kilograms 100 kilograms 1 tonne 100 kilograms 4 VAB.0001126747 4 - 28 - TEPP 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) Tetramethylenedisulphotetramine Thlonazin Tlrpate (2,4-Dimethy1-2,3-dithiolane- 2-carboxaldehyde 0-methylcarbamoyloxlme) Trichloromethanesulphenyl chloride 1-Trl(cyclohexyl)s tannyl-lH-1,2,4-trla zole Triethylenemelamine Warfarin 100 kilograms 1 kilogram 1 kilogram 100 kilograms 100 kilograms 100 kilograms 100 kilograms 10 kilograms 100 kilograms Group B: Other Toxic Substances (Quantity > 10 tonnes) (See definition Appendix II, Page 20) Acetone cyanohydrin (2-Cyanopropan-2-ol) 200 tons Acrolein (2-Propenal) 200 tons Acrylonitrile 200 tons Allyl alcohol (2-Propen-l-ol) 200 tons Allylamlne y Ammonia 200 tons 500 tons Bromine 500 tons Carbon disulphide 200 tons Chlorine $0 tons Ethylene dibromide (1,2-Dlbromoethane) 50 tons Ethylene inline 50 tons Formaldehyde (concentration > 90%) 50 tons Hydrogen chloride (liquefied gas) 250 tons Hydrogen cyanide 20 tons A VAB.0001126748 - 29 - Hydrogen fluoride Hydrogen sulphide Methyl bromide (Bromomethane) HLtrogen oxides Phosgene (Carbonyl chloride) Propylenelmlne Sulphur dioxide Tetraethyl lead Tetramethyl lead 50 tons 50 tons 200 tons 50 tons 20 tons 50 tons 1000 tons 50 tons 50 tons Group C.l: Highly Reactive Substances and Explosives Acetylene 50 tons Ammonium nitrate (where it Is in a state which gives It properties capable of creating a major accident hazard) 5000 tons 2,2-Bis(tert-butylperoxy) butane concentration > 702) 50 tons 1,1-Bis (tert-butylperoxy) cyclohexane (concentration > 80%) 50 tons tert-Butyl peroxyacetate (concentration) > 70Z) 50 tons tert-Butyl peroxylsobutyrate (concentration > 80Z) 50 tons tert-Butyl peroxy isopropyl carbonate (concentration > 80%) 50 tons tert-Butyl peroxymaleate (concentration > 80%) 50 tons tert-Butyl peroxyphlvalate (concentration > 77%) 50 tons VAB.0001126749 4 - 30 - D1benzyl peroxydlcarbonate (concentration > 90%) 50 tons Di-sec-butyl peroxydlcarbonate concentration > 80%) 50 tons Diethyl peroxydlcarbonate (concentration > 30%) 50 tons 2,2-Dlhydroperoxypropane (concentration > 30%) 50 tons Dl-isobutyryl peroxide (concentration > 50%) 50 tons Di-n-propyl peroxydlcarbonate (concentration > 80%) 50 tons Ethylene oxide 50 tons Ethyl nitrate 50 tons 3,3,696,9,9-4Iexamethyl-l, 2,4,5tetroxacydononane concentration > 75%) 50 tons Hydrogen 50 tons Methyl ethyl ketone peroxide (concentration > 60%) 50 tons Methyl Isobutyl ketone peroxide (concentration > 60%) 50 tons Peracetic acid (concentration > 60%) 50 tons Propylene oxide 50 tons Sodium chlorate 250 tons Group C.2: loslve Substances Barium azide Bis (2,4,6-trinitrophenyl) amine Chlorotrlnltrobenzene Cellulose nitrate (containing > 12.6% nitrogen) 50 tons 50 tons 50 tons 100 tons A VAB.0001126750 rf* - 31 - Cydo te trame thyl enetetranl tramine Cydotrlmethylenetrlnltramlne D1azondinitropheno1 Diethylane glycol dlnitrate Dinitrophenol, salts Ethylene glycol dlnltrate l-Guanyl-4-nltrosamlnoguanyl-l-tetrazene 2,2*,4,4f,6,6'-flexanitrostilbene Hydrazine nitrate Lead azide Lead styphnate (Lead 2,4,6- trlnltroresorclnoxlde) Mercury fulminate N-Methyl-N,2,4,6-tetranltroanlllne Nitroglycerine Pentaerythrltol tetranltrate Picric acid (2,4,6-Trlnltrophenol) Sodium plcramate Styphnlc acid (2,46,6,-Trlnltroresorclnol) 1,3,5-Trlamlno-2,4,6-Trinitrobenzene Trlnltroanlllne 2,4,6-Trlnltroanlsole Trlnltrobenzene Trlnltrobenzolc acid Trlnltrocresol % 50 tone 50 tons 10 tons 10 tons 50 tons 10 tons 10 tons 50 tons 50 tons 50 tons 50 tons 10 tons 50 tons 10 tons 50 tons 50 tons 50 tons 50 tons 50 tons 50 tons 50 tons 50 tons 50 tons 50 tons i VAB.0001126751 32 A 2.4.6-Trinitrophenetole 50 tons 2.4.6-Trinitrotoluene 50 tons Group D: Flammable Substances Flammable substances as defined in D*1 below 200 tons Flammable substances as defined in D.2 below 50,000 tons Flammable substances as defined in D.3 below 200 tons D*1 Flammable Gases Substances which in the gaseous state at normal pressure and mixed with air become flammable and the boiling point of which at normal pressure is 20C or below* D.2 Highly Flammable Liquids Substances which have a flash point lower than 21C and the boiling point of which at normal pressure is above 20C* e- D.3 Flammable Liquids at High Temperatures and Pressure Substances which have a flash point lower than 55*C and which remain liquid under pressure, where particular processing conditions, such as high pressure and high temperature, may create a major accident hazard* 4 VAB.0001126752 f! 33 - A Appendix IV Section 4.2.3 specifies the details required to be included in a full safety case study prepared in accordance with these guidelines The details required in Section 4*2*3 are discussed below as separate items but it Is for the developer to determine the most appropriate or convenient method of presenting the required information. In particular, general Issues (e.g*, pressure vessel inspection arrangements) could be referenced and any variations or departures from the generally accepted practice mill suffice* The item-by-item guidance given below in relation to Section 4*2.3 is by example rather than by lists of topics to be covered* The latter approach suffers the twin disadvantages of not being truly comprehensive while at the same time giving the impression that each listed topic Is of equal Importance* In practice, the depth of information required on each topic will vary according to the circumstances of the individual installation* Sections 4*2*3.1 and 4.2.3.2 require factual information about the dangerous substances and the installations handling them* Section 4*2.3.3 relates to the management control of the activity* Section 4.2*3*4 requires information about the sources and nature of potential major accidents and the measures taken to prevent and control them* Section 4.2.3*1 (Substance Name) The Information required under this sub-heading is concerned with identifying the dangerous substance which qualifies the activity or storage for the requirement to make a full safety case study; the wording should be self-explanatory* Where standard analytical methods are used by the firm this item need only identify the method and any departures from it. Provision of gas detection equipment could be referred to here or left if appropriate to the discussion of preventive measures under Section 4.2*3.4. VAB.0001126753 P 34 Section 4.2.3.1 (Hazards of the Substances) Information given under this sub-item should cover (a) the route of the harm to man (skin contact, Inhalation or ingestion for toxic substances, and flame contact, thermal radiation or blast for flammable or explosive substances); (b) the dose-response relationship, where known, citing standard published references as appropriate (e*g*, the Chemical Industries Association's table of the toxic effects of chlorine at various concentrations); and (c) the nature of the trauma, where this Is not obvious (e*g*, chloracne from exposure to dioxin)* In relation to the hazards from the substance to the environment, information is not required about the obvious effects of flame or blast from explosive or flammable substances* For toxic substances such Information as Is readily available should be given or be referred to. Including the route of the harm (e*g*, the pollution of water courses); the effect on flora and fauna which may be exposed; and an indication of the substance's persistence* Section 4*2*3*1 osition of Process Streams) This item requires information about the composition so that the effects of diluents or impurities which significant effect on the hazard can be assessed* For example, where an organic peroxide is present in an activity, the name of any stabilizer should be given* The presence of significant quantities of impurities could also affect the behaviour of a substance and these impurities and their percentages should also be identified* An example would be the alteration of the toxic properties of chloromethyl methyl ether by the presence of bis (chloromethyl) ether* It is not necessary to list the minor components of mixtures being processed where these have an insignificant effect on the potential hazard (e.g*, a hydrocarbon mixture might be described as 70% butane, 25% propane, 5% higher hyd rocarbons) Section 4.2*3*2(1) (Location) This map is required to indicate where the installation Is located, showing Its position In relation to local geographic features, such as roads and towns* In general it will be sufficient to use the latest available map or maps on a scale which Includes both the site and the surrounding features* Changes (such as a new motorway) which have occured since the printing of the map and which are known to the firm should be shown; it is not intended that this should involve any extended research effort* For many sites a scale of 1 to 10,000 will be appropriate* VAB.0001126754 i Section 4.2 an The intention of this Item Is to Identify clearly, both In location and quantity, the main parts which contribute to the total Inventory of the dangerous substance* In addition, the plan should be annotated to indicate the lesser quantities which make up the stated total* For example, an estimate of the quantity of the substance which is present In pipework around a particular plant should be made* It may be convenient to combine the response to this item with that to Section 4*2*3*4, and in particular, Section 4*2*3*4 item <ii>- Section 4.2*3*2(111) (Process/Flow Description) The intention of this requirement is that a sufficient description of the process be given to enable discussion on later items to be understood and placed in context* The amount of description required will depend on the complexity of the process* For example, a water treatment plant using chlorine will require only a brief account of the water dosing process, whereas a chemical plant producing qualifying quantities of a very toxic substance as an intermediate will require sufficient information to enable the critical aspects of the process chemistry to be understood* In this latter example, the information will be supplemented by the information given under Section 4.2* 3* 4 and it will be for the manufacturer to determine the most appropriate method of presentation The conditions under which the substance is normally held should be stated, including the physical state and pressure and/or temperature at the main stages of storage and process, e*g, butane is held In storage as a refrigerated liquid at 0*C; vaporized in a direct-fired evaporator and fed as a gas to a process vessel at 10 bar, 90C* Section 4*2*32(lv) (Personnel on site) The number given should be accompanied by sufficient explanation to show how it was derived* Account should be taken of the number of people who may be present at shift changeover; people who may be employed from the site but who may be present only for short periods (eg., sales staff or delivery drivers); regular visitors to the site (e.g., contractors); and casual visitors* Exact numbers are not required* Land The information required is about the use of land or water surrounding the activity and the location of people who may be affected in the event of a major accident. This can be provided by VAB.0001126755 4 annotations on a suitable map. Indicating broad categories of land use (e*g*, dwellings, other factories, schools, sports facilities, agricultural land, etc*)* It la not necessary to give numerical estimates of population in the areas covered by each category, though any unusually high densities such as shanty towns, blocks of flats should be marked as such* The choice of the phrase 'in the vicinity of' rather than definite distances is Intended to allow for flexible interpretation in relation to the potential hazard* For example, for e flammable liquid tank farm the 'vicinity' might be less extensive than for bulk chlorine storage* A degree of judgment is thus called for and a brief explanation should be given of the choice of vicinity illustrated on the map* The aim of this item is to demonstrate that the developer has a proper lanagement system and technical staff to control the major hazard aspects of his activities* The reauired information is general. Insofar as it relates to the management control of the site as a whole,' in contrast to the greater detail that may be needed under Section 4.2.3.4 to demonstrate that there are adequate arrangements to prevent and control particular hazardous events* The extent of the response to this item should be seen against its importance in providing a framework In which the rest of the safety case may be set and which will to some degree color the credibility of the whole submission* Section 4*2*3*3(1) (Responsible Person and Staffing) A description of the management structure should be given which covers reporting relationship and the experience and qualifications of staff at the different levels* It is important to show how accountability for decisions which affect the potentially hazardous activity is assigned to staff who have the appropriate level of expertise and the relevent professional discipline* Reference should also be made to the developer's policy towards the appointment of competent deputies to cover key positions* This section should also cover the arrangements which management have set up for identifying and dealing with safety issues arising from the potentially hazardous activity, with references as appropriate to the group, division and site safety policies, and the role of safety representatives and safety committees* This section should Include an account of how management decisions about the potentially hazardous activity are made with due regard for their safety Implications, and how these decisions are monitored* S VAB.0001126756 - 37 Section 4.2.3.3 "*rr alit Control for Safet The Importance of the containment of dangerous substances is i require an adequate account of the management of the engineering This manufacturer*3 approach to the design of important plant items safety systems (e.g., use of standard or company codes); the arrangements for quality assurance; the inspection and testing procedures (who carries them out? how frequently? who decide necessary action in the event of deficiencies being discovered who monitors these actions and how?); the provision of operating manuals and instructions* and the procedures for revising them In the event of process changes; the procedures for ensuring that plant modifications are adequately designed) Installed and tested; and the system for veneral maintenance The response to this item should not contain lengthy abstracts from written company procedures) but should aim to give a coherent justification for the system of engineering controls exercised over the potentially hazardous activity. Section 4.2.3.3(111) (Training) Information should be given about the standards of relevant training, both on- and off-the-job, for people on site with a significant role In the control or operation of the major hazard activity, including the senior management and engineering staff Involved. A brief account should also be given about how training needs are identified and met. Section 4.2.3.4 (Potential Major Accidents) # The response to this Item will provide the heart of the full safety case. Though the information required is specified in some detail, it will be essential for developers to Interpret this item with commonsense and flexibility. As noted above in the general discussion of the term, 'full safety case*, it will be for the developer to judge which potential major accidents should be investigated and discussed in his safety case, and then to decide the extent of the evidence necessary to support his conclusions. Section 4.2.3.4(1) (Identification of Potential Major Hazard Events) This item requires the manufacturer to identify the ways in which a major accident might occur. "Major accident" is defined in Section 2 and guidance on its interpretation Is given in this section. Suitable techniques for identification are hazard and operability studies, engineering flow chart review, and review of past accidents and near misses., Tmhee concepnt of the safety case allows the opportunity to argue in the response to this item that A p VAB.0001126757 his activities are not capable of giving rise to a major accident, provided that they are satisfied that such an argument can be fully and properly justified* In some cases9 a submission of this sort may be relatively easy to support* For example, a toxic hazardous substance may be stored In separate cylinders, and the quantity In each one may not be sufficient to give rise to a major accident* If the cylinders mere disposed around the site so that the possibility of of an Incident affecting them simultaneously could be ruled out, then the argument that a major accident cannot arise on the site may be reasonably straightforward* In other cases the evidence necessary to justify such an argument may prove to be as extensive as a response to this item which accepts that major accidents may occur, and then goes on to describe how they are prevented; It will be for the manufacturer to decide Initially which option better fulfills the objectives of the safety case* If it can be shown that the activity is not capable of giving rise to a major accident, then the remaining parts of Section 4*2*3*4 need not be answered* It Is In this section that the i quantification of the magnitude of hazardous events and their frequency by means of hazard and risk analysis techniques are required In most cases it will be necessary to describe the potential sources of a major accident* Storage and process vessels which contain significant quantities of the dangerous substance should be examined for the most probable ways in which their inventories may be released, and these should Include consideration of, spontaneous failure (due to original defects or those arising In the course of operation); failure due to excursions from normal operating conditions (Including such matters as operator error, loss of services, and failure of control devices); failure due to events elsetfiere on site (e*g*, fire, explosion); and failure due to external events (e*g*, flooding, seismic activity)* For a complex chemical or petrochemical works or a refinery, where the number of vessels and pipes for individual plants may be very large (but built to common standards), it may be appropriate to be more selective in examining the potential sources of a major accident by considering only the largest vessels in detail and then referring to smaller vessels or groups of vessels in general terms* * Section 4*2*3*4(11) (Process Flow Diagrams) This Item calls for judgment by the developer as to which sections of the plants containing the dangerous substance need to be Illustrated In diagrammatic form* Such diagrams should show the process vessels, storage facilities and Instrumentation on the plants concenred In sufficient detail to enable the discussion under Section 4*2*3*4 (1) and (ill) to be readily understood* For vessels In the plants which have been identified in Section 4.2.3.4(1) as significant as regards the potential for a major accident, details should be shown on the diagram of their designed maximum working capacities, their VAB.0001126758 39 A design temperatures and pressures, and their normal operating conditions* It may be convenient to combine this with the response to Section 4*2*3.2(11)* For example, a large vertical cylindrical storage vessel containing the dangerous substance would require a diagram showing the vessel. Its connections. Instrumentation and external safety features such as water sprays and bunds; for complex plants diagrams of only the largest or most significant vessels are required Section 4*2*3*4(111) (Preventative and Control Systems) I The third part of Section 4.2* 3.4 requires a response in two parts* First, relating to the preventive and control measures which check any sequence of events which could foreseeably result In a major accident, and secondly, relating to measures which may be taken after such a hazardous outcome to minimize Its adverse consequences* It Is Important to realize that It Is better to prevent a release occurring rather than trying to control the consequences, which may, in part, be Impracticable The first part of the response should concentrate on those preventive or control measures which are critical in counter-acting significant hazards, though many of these measures will also be appropriate to preventing or controlling lesser events* The interpretation of certain key words In this part of Section 4*2.3*4 may usefully be discussed in relation to examples; say, a large pressure storage sphere of IPG, representing the risk of fire and explosion, and for an example of toxic risk, a large pressure storage sphere of ammonia* "Measures taken to prevent" relate to ensuring the safe operation of the plant under normal operating conditions or within specified process limits* They are those measures which are Intended to prevent the initiation of a sequence of events which could lead to a significant hazardous outcome and would include consideration of design, engineering standards, constructional and quality assurance, inspection and maintenance, and control systems insofar as these were concerned with controlling the process during normal operation* These preventive measures derive their validity from the way in which the overall management of the plant and company exercises control over them and ensures their effectiveness* Thus, a sufficient account of the relevant parts of the management system, expanding on the general information given in Section 4.2.3*3 will be needed to support any arguments about the probability of initiating a sequence of events with a hazardous outcome. In relation to the ammonia sphere example, "measures taken to prevent", would include a discussion of the arrangements for checking ammonia purity and special vessel inspections In connection with the problem of stress corrosion cracking * * VAB.0001126759 V "Measures taken to control relate to the interventions pexnitted by the design of the plant (e.g, valves) or safety hardware (t,g.t dump tanks) which may counter an event so that the dangerous substance is retained within the plant* The operation of a "measure taken to control" assumes that a sequence of events has been initiated and the control is Intended to prevent the sequence proceeding to a major accident* In relation to the LPG sphere example, a spillage of LPG near the tank which Ignited, could be prevented from escalating to a BLEVE (boiling liquid expanding vapour explosion) of the whole sphere by the effective operation of a water spray system on the sphere* The discussion of this control measure should Include reference to the the capacity of the water storage system, the water application rate; how the company ensures that the system will in fact operate effectively when required to do so; and the system reliability* The second part of the response to this item covers "Measures to minimise the consequence", which relate to those measures which can be taken after the major accident has actually occurred* Examples of minimization Include: bunding, water curtains, foam blankets, and emergency procedures* In relation to the ammonia sphere, the effects of a release of ammonia from a pipe at a sufficient rate to lead to a lethal concentration of gas at (say) the nearest domestic dwellings might be minimised by the application of a water curtain around the sphere, and, through the emergency services, by evacuation of those people who are downwind of the escape* Section 4*2*3*4 (ill) refers to the prevention or control of major accidents identified in Section 42*3*4(1)* It is therefore not necessary to Include Information, about measures directed solely at preventing small releases or those which have only minor consequences, unless these have the potential to escalate to a major accident* Section 4*2*3*4(111) by concentrating on preventive measures, is intended to draw out discussion on the positive aspects of the full safety case* However, because the sequence of cause, effect and consequence are closely intertwined, it Is not possible in practice to confine such a discussion to prevention without mentioning the potential consequences of the potential major accidents discussed In the safety case* Estimates of consequences will in any case be required in order to formulate adequate advice to the authority responsible for drawing up off-site emergency plans (see Section 5). Section 4.2*3.4 (Iv) (Emergency Procedures) * Section 5 requires the developer to produce a plan for dealing with emergencies on-site* The operator/developer should be able to present the whole document for examination if necessary, but that is not the intention of this part of the safety case* On the other hand, it will not be sufficient merely to state that the a VAB.0001126760 emergency plan exists* The response to this item should describe the procedures in outline; indicate the nature and extent of emergencies with which the plans are Intended to cope, drawing as necessary on the information in other parts of the safety case; mention those arrangements which may be critical to the success of the plans such as access for emergency services, the provision of adequate supplies of fire-fighting water, the remote siting of emergency control points and the evacuation of non-essential site personnel; and confirm that the plans have been discussed with the relevant outside bodies and practiced with them* Section 4*2.3*4 (v) (Meteorological Conditions) Data should be obtained from the nearest Meteorological Office weather station as to the prevailing weather conditions in the vicinity of the site, and if necessary confirmed by actual measurements on the site* (vi) (Numbers at Risk) This estimate should Include those people normally working on the plant concerned and any major concentrations of people In the immediate vicinity of the plant, e*g, office buildings* As for Section 4.2>3*2 (lv), exact numbers are not necessary* A + VAB.0001126761