Document 7O5njBzrJMK3e8ZEQmg6DjeZE

not increase and urine lead levels decreased. Some details of the study were presented by Martha McLaughlin of DuPont's Haskell Laboratory for Toxicology and Industrial Medicine ("Wilmington, Del. 19898) at the American Academy of Occupational Medicine's annual meeting in New Orleans, Feb. 5-7: Selected for the study were personnel from 23 DuPont plants in widely separated geo graphical locations ranging from semi-rural to large metropolitan areas. None of the operations of any plant involved known occupational lead exposures. Any trends in lead levels in the group studied would be expected to be similar to those of the gene ral U. S. population. To maintain the original sample size, it became necessary at the beginning of the third year to add replacements at each location to make up for sub jects lost due to transfers and early retirements. Annually, a urine specimen was collected from each subject and blood specimens were collected from 10% of the subjects. All specimens were sent to the Medical Laboratory for lead analysis. The first set of statistical analyses utilized data from subjects with five years of blood lead or urine lead values. The second set of analyses included data from all subjects involved during the study. Yearly mean blood lead values for both sets of data were similar. Yearly mean urine lead values for all subjects were similar to the mean values for the subjects with data for all five years. Although the analysis of variance for subjects with five years of data indicated signifi cant differences between years for both blood lead and urine^Ttead, there was no appar ent time trend in the mean'blood lead values, but the mean urine lead values decreased throughout the course of the study. Analysis of quality control data for the urine lead measurement, selection of data for statistical treatment, and seasonal effects did not provide an explanation for the downward trend in urine lead levels. UTILIZATION OF SURFACE REFLECTIVITY FOR OPTIMUM LIGHTING The reflectivity of a factory's ceiling, walls, and floor contributes to the utilization of the lighting system, it was pointed out by Gordon D. Rowe of General Electric Company (Nela Park, Cleveland, Ohio 44112) at the 24th Plant Engineering and Maintenance Con ference in Chicago, March 12-15. He gave the following as recommended minimum re flectances of surfaces: Ceiling (all area above fixture line). ............ Walls.................................,.............. ................................................ Desk and Bench Tops, Machines and Equipment. . Floo rs........................................................,.................................. . ....... .80 to 90% reflectance ....... .40 to 60% reflectance .................25 to 45% reflectance Not less than 20% reflectance The effect of proper room-surface finish on the amount of light that a specific light ing system delivers can be evaluated by inspecting a luminaire's "coefficient-of- utilization" table which gives percentages of useful light reaching the work plane for a typical 400-watt Lucalox fixture. Where the respective ceiling, wall reflectances are 80 and 50%, the utilization will be 23 to 27% higher than if these reflectances were 10 and 10% -- a condition that can exist in a poorly maintained factory space. Illumination levels are directly proportional to the utilization factors, according to Mr. Rowe, thus, for a specific number of fixtures, proper room reflectances will increase the illumination or fewer fixtures will be required for a specific lighting level. Room colors should be selected for optimum light utilization and environ mental acceptability, he added. N27016 Annual subscription rate in U.S.A, and Canada, $15.00; in other countries $16.00. Reproduction of complete issue prohibited. Up to q Jj P040005886 Fox the first time* the capability fox at least semiquantitative correlation of CO body burden with industrial exposure in the TLV range has become available. Therefore, in future surveys, CO analysis of breath samples collected at the end of the four-hour sam pling period can provide correlation with the time weighted average dose inhaled by the employee during the time spent in his workplace. The most significant feature of this type of monitoring is the capability for instantaneous read-out. At any time the accumu lated dose can be quickly estimated from the 1, 2, 3 and 4-hour calibration charts. Con tact with a pocket of high CO concentration would immediately turn the entire tube from amber to black to give the wearer ample warning to immediately leave the area, DESIGN, INSTALLATION, AND PROVE-IN OF PLATER FUME SCRUBBING SYSTEM To meet the need for exhausting and fume scrubbing 25b, 000 cfm of air at the plating operations of Western Electric Company's Oklahoma City Works, a unique system was designed and installed which has produced encouraging results based on limited testing to date. Some considerations in the selection of the equipment and the problems encoun tered in proving in the equipment were outlined by A. E. Jamison at the 24th Plant En gineering and Maintenance Conference in Chicago, March 12-15: On the basis of efficiencies, versatility and total cost, the extended surface scrubber and the vertical packed tower scrubber were selected. Extended surface scrubbers are very attractive because of the low water flow, and the once-through-the-unit fea tures which eliminates the need for recirculating equipment. Ten single-stage units of this type with capacities ranging from 8, 000 cfm to 25, 000 cfm of air were eventu ally installed. By the time the last of the scrubbers was ordered, the suppliers of the extended surface scrubber had changed the design to utilize an in-line centaxial fan which is cheaper and less expensive to install. The vertical packed tower scrub ber has great versatility in that the packing depth can be varied to improve the effici ency, and chemicals can be added to the recirculating tank to support the removal of special contaminants. Four packed tower scrubbers, utilizing conventional centrifu gal fans, were installed. In proving in the extended surface scrubbers, it was found that the Nylon reactions and eliminator pads furnished by the supplier lasted only about three weeks. A change to a rubber-coated hair pad has proved much more satisfactory since its useful life is about three to five months. After approximately six months of operation, the only problem with the packed towers was the appearance of water carryover. A chemical treatment corrected the cause of this -- a foreign growth in the pads on the extended surface scrub bers on cyanide processes. Problems were encountered with the in-line centaxial fans that were installed on the extended surface scrubbers on acid exhaust. Three weeks after installation, it was found that the elastoglass coating had failed due to deterioration of the fan blades attributed to water droplet carryover and to cracks in the coating caused by the intense vibration which allowed the acid to attack the metal. The problem was solved when one supplier agreed to furnish an in-line fan of all fiberglass reinforced plastic. In tests completed on an extended surface scrubber without work on the hydro gen chloride tank, 97% efficiency was attained. With maximum work, efficiency was 94%. EVALUATION OF AN ENVIRONMENTAL CONTAMINANT: DEAD In spite of progressively increasing amounts of lead that have been mined and distribu ted throughout our environment in recent years, it was found in a five-year study of 6, 000 DuPont employees non-occupationally exposed to lead that lead levels in blood did i ; DW S io s s s s s 87 for an appreciable fraction of the smog "-potential of the exhaust was described at the' Automotive Air Pollution Research Symposium in Washington, D. C. March 7-9. Because wet chemical methods have been widely applied in analysis of exhaust gas, the resulting determinations of carbonyls have been commonly accepted as measurements of "oxyge nates, " according to R. W. Hurn of the Bureau of Mines' Bartlesville Research Center (Bartlesville, Okla. 74003), who said that this assumption is not justified. This conclu sion is based on results of the following studies: Experiments were made using a 1970 model compact vehicle equipped with a 6-cylinder, 170-CID engine outfitted in each of two configurations: one with standard 1970 modelyear engine modifications for emission control, and the other with an oxidation cata lyst added in the exhaust system. -Secondary air was. supplied in the second configura tion. The fuels were an unleaded full-boiling range gasoline typical of XJ. S. summer regular grade plus a series of hydrocarbons that represented the principal hydrocar bon types in a full-boiling range gasoline. Rationale in the choice of the fuel compo nents was to obtain data on oxygenate yields for each of the hydrocarbons. These data then would be combined in a synthesis to predict yields from a composite blend that would approach the characteristics of a full-boiling range gasoline. A variable rate proportional sampler was used to obtain sample upon which measurements were made for hydrocarbon, carbon dioxide, carbon monoxide, and oxygentates. The following findings are based upon the levels of oxygentates estimated from data ob tained in experiments using single component fuels in the vehicle not equipped with an exhaust oxidation catalyst, and upon levels of oxygenates determined directly by analy sis of exhausts produced using a full-boiling range fuel in the vehicle equipped with an oxidation catalyst: (1) noncarbonyls may (but not necessarily always) constitute a signi ficant fraction of exhaust oxygenates, and (2) the compositional character and class dis tribution of oxygenates in the exhaust from catalytic systems may differ significantly from that composition and distribution for oxygenates not subjected to catalytic conversion. NEW APPROACH TO PERSONNEL MONITORING FOR CARBON MONOXIDE Because of the deficiencies encountered with the fixed point alarms, grab sampling, and infrared monitoring in determining compliance with the TLV for carbon monoxide within a consolidated warehouse where gasoline -powered forklift trucks are used to store drums within bays and for loading boxcars, a different approach to personnel monitoring was adopted. Adrian L. Lunch of E. I. du Pont de Nemours & Company (Chamber Works, Deepwater, N. J. 08023) discussed the method at the American Academy of Occupational Medicine meeting in New Orleans, Feb. 7-9. None of the available colorimetric or instrumental methods could be adapted to per sonnel monitoring, therefore, the Kitagawa CO Detector Tube was recalibrated for four hour continuous sampling. Although the best accuracy that could be attained lay tin the 25% range of the true value, the method sufficed to determine compliance with the TLV (0. 5, 1 and 2 times 50 ppm). On the other hand, certain limitations must be observed. The flow rate is critical and must be maintained at 8. 0 - 1.2 ml/min and the useful range is limited to 30 to 100 ppm. The second generation instrument will include a microrotameter which will permit precise control of flow rate and thereby compensate for the variability in pressure drop from tube to tube which should improve the accuracy. With sampling rates in the 6. 5 to 10 ml/min range, the response of the reagent stain is not proportional to CO concentrations below 30 ppm. Calibration must be carried out with CO standards made up in air, not in nitrogen. . . `2` dw n Volume 16 April, 1973 Reporting on new developments In indnstrial hygiene, air pollu tion control and environmental health. Annual subscription: $15.00. Published monthly by Flournoy & Associates, 1845 W, Morse, Chicago, 111. 6062$. Editorial Consultants: Wiliam T, McCormick Herbert T. Walworth Number 4 THINGS TO COME: EPA's NEW SOURCE PERFORMANCE STANDARDS The Environmental Protection Agency has ready for proposal a new group of New Source Performance Standards that cover facilities in seven categories, it was reported by Donald F. Walters of the Office of Air Quality Planning and Standards (Research Tri angle Park, N. C. 27711), at the annual meeting of the Technical Association of the Pulp and Paper Industry in Chicago,. March 5-7, He listed the following sources, pollutants of concern and affected facilities: Source Asphalt concrete plants Petroleum refineries Gasoline, crude oil and petro leum distillate storage tanks Iron and steel mills Sewage treatment plants Secondary brass or bronze refining facilities Secondary lead smelters and refineries Affected Facility Dryer; hot aggregate elevator screen ing equipment; hot aggregate weigh ing equipment; mineral filler loading, transfer and storage Process gas burned in process heat ers, boilers and waste gas disposal systems Catalyst regenerators Storage vessel of more than 65,000 gallon capacity Basic oxygen furnaces Sludge incinerators Reve rb era to ry furnac e s Blast and reverberatory furnaces Pollutant Particulates Sulfur dioxide Particulates Carbon monoxide Hydrocarbons Particulates Particulates Particulates Particulates Mr. Walters also mentioned that development of standards is well advanced for copper, lead and zinc smelters, with reference to particulates and sulfur dioxide. Other industrial categories that are candidates for proposed New Source Performance Standards about August, 1973, and the pollutants of concern are aluminum reduction plants (fluor ides); ferro-alloy plants (particulates); coal cleaning plants (particulates ); kraft pulp mills (total reduced sulfur); iron and steel mills (particulates and carbon monoxide); phosphate fertilizer plants (fluorides); and gas turbines (particulates, nitrogen oxides, and sulfur oxides). METHODOLOGY FOR MEASUREMENT OF OXYGENATES IN AUTO EXHAUST GAS A method for measuring oxygenates, a class of partly-burned hydrocarbons, which under certain circumstances can be produced in auto exhaust gas in sufficient quantity to account DU P040005889 Diana Lead Data Entry Coding Form: BatesBegm DUP0400058S0 Doc Type I Letter BatesEncr Year Date TotalPages 1973 Month Date DecControl#1 313.01 1 Attaint'# 0 4 L'ir T. i` - 12 Title Enclosed is a copy of our current issue whicn contains a report on a paper you recently presented -- one Reference1 we believe our readers will find most interesting Primaiy Author Last Name. Flournoy Secondary Authors. Industrial Hygiene News Report Primary Martha McLaughlin Recipient (s)1 CCs First Name. Middle Initial Dons Publication Names Stated Chicago Illinois Flournoy & Associates Haskell Laboratory DuPont Wilmington Delawaie Doc Problems Case Produced In j Steven Thomas | Produced By j DPT Dup/Cross Ref #'s Doc Control Comments Disk, Box 1, January 2002, SH001001 -SH001002 Source j Responswe to Plaintiffs 1 st Re Ob). Coder Nam | D Green Obj Data Entry Nam | D. Green ObjDataDate 9/4,2002 N 27016.01 Publish** by FLOURNOY & ASSOCIATES industrial hygiene news report 18 45 WEST MORSE AVENUE, CHICAGO, ILLINOIS 60626 Martha McLaughlin, B.A., Physiologist Haskell Laboratory for Toxicology & Industrial Medicine E. 1. du Pont de Nemours & Co, Wilmington, Del. 19898 April 12, 1973 Dear Ms. McLaughlin: Enclosed is a copy of our current issue which contains a report on a paper you recently presented -- one we believe our readers will find most interesting. We hope that our write-up meets with your approval. Thank you for the privilege of reporting on your work. Sincerely yours, DF: le enc. current issue Doris Flournoy, M.S. Managing Editor DUP040005890