Document KR2qkgJXo4yQn1e3vOa9oNG4X

byi Con PFroeest, Lab MKaannaa.xtor & W. D. Resonagel, P,t., President R0S3HAGEL * ASSOCIATES Engineering * Tasting Consultants Cherry Hill. N.J.f k Atlanta, Ca*i Paintsvllle, Ohio Th Wllllams-Stelger Occupational Safety and Health Act of 1970, commonly known as O.S.H.A. regulations, contains over 7,000 codes. In thl3 paper we will review some of the substances on which II.I.O.S.H. (national Institute of Safety & Health), a branch of H.E.W., prepares . criteria documents for use by O.S.H.A. When O.S.H.A. initiated the Target Health Hazards Program in January o/ 1972, three of the primary contaminants of concern wore as'ojston, silica and cotton dust. H.I.O.S.H. maintains a current Hot of criteria documents for oxpocure to more than twenty hazardous materials, Tht O.S.H.A, codes required that sffsetlvo August 27, 1971, (on* capt for asbestos) all plants with employees exposed to du3t or fibers above the proposed limlt3 stated in tho FEDERAL REGISTER, ba provided with protective enuloment and the operation analysed to determine if 'cne contaminants can be eliminated or reduced at the source. This means that it is not enough just to give the operator a breathing mask - but rather definite steps must be takan' to reduce the con* taninant level. The similar effective data for asbestos was June 7, 1972. A detail analysis of the requirements of these three materials followwst* ^ A. Asbestos is a general term used to describe several fibrous mineral silicates that occur as white, gray/blue or green masces, jlther compact or of long silky fibers. The most important types arti Ohrysotile - a simple magnesium silicatei Amosite * 'a complex magnesium Iren silicatet Crocidolite a complex sodium iron 3ilicate, Soeo 95 percent of the world asbestos production come3 from Chrysotile. The principal danger of asbestos fibers is caused by inhaling. Prolonged .'..-.halation of'asbestos fibers and du3t of 5 or sore microns ler.a-millionth of a meter or 1/25.000 of an inch) long can produce a lun.i disease known as ssbestosls, a diffuse, interstitial, nohtuglignant. scarring of tho lunrs. The nasal pharangeal area and bronchial tubes tend to remove the nonrespirable particulates and then dispel them by ciliary action. If this exposure continues for 10 to 20 years, the tissue reaction progresses until a generalized, diffuse flbrosle occure, causing severe respiratory disability including lung cancer. The respirable fibers and dust may cause a mesothelioma (lining of the lung or gut) or even gastrointestinal concor to develop. Tha analysis of filters containing asbestos fibers is much more Ufflcult. This requires at least a S3,000 trioctal microscope with phase contrast optics and an attached focuaable Polaroid camera, 4 Revised Sept. 1976 1 MAR 000852 *>3 microscope should be located In a laminar flcv/ booth or in a .iipirate, clean room with temperature and humidity controls, Most important, it requires a sKillod technician trained in the filter handling and optical procedures and with the patience to perform the required statistical sampling techniques. Figures on ?ite 4 show labestos fibers at various magnifications with the Psrtcn recticle tj background. The statistical counting plan requires counting fibers m detailed later in the lab Analysis section. Sotuetir.es it is r.cces- *xy to count the fibers in 100 or more "fields'' in the Forton recuicle. ;:-his has been cotsparad with searching on your hands and knees to count feur leaf clovers in a one acre field! The O.S.H.A. codes currently require evory erpleyeo exposed to asbestos fibers to bo tested at leant evr> nix months and the records be maintained for review by O.S.H.A. representatives. O.S.H.A. codes state employers shall provide a medical examination v/ithin 30 days of the employees' first occupational exposure to asbestos and provide at least an annual examination thereafter. Also .an examination is required within 30 days of termination of employment. These requirements axe fully detailed in Reference (10). Many plant engineera/hygienists are r.ot aware that as of July 1* 197o, the O.S.H.A. limits on airborne asbestos era core rostrictivo as shown in Table A. Tho future proposed codos arc also shown belowi SUMMARY OF ASBESTOS RECUiaEMS^TS - in flberr/nl Primary Requirements Cod# Present Code Proposed Since 6/7/72 at of 7/1/76 Code 1. Allowable Ceiling Limit 10 fibers* 10 fibers* 5 fibers* 2. Allowable TWA (Time Weighted Average) for 8 hours exposure 5 fibers* 2 fibers* 5 fibers* * fiber defined a3 larger than 5 microns in length and having on aspect ratio of at least 31 TABLE A The following page is taken directly from an asbestos test report conducted by ROSSHAGEL k ASSOCIATES. The Table Z results. listed in the column heeded "Extrapolated TWA 5 ^ or longer fibers" shows three . .men's exposure .above the 2 fiber limit (the limit allowed after July 1, 1976). These asbestos levels wers retched in s process of handling .'.jhjatos pallata. On Pars 4 are photomicrographs showing the high denoity of aabiatoi fibers in this ta3t. The photomicrographs show fibers of 5 10 *^6 27 microns in sise* MAR 000853 .V.bla Z belowi ASBESTOS FI3SR counting RESULTS am- Per le sonal 0. Samole No. Location/ Activity FIBERS 5ju or longer with an aspect ratio of at least 3il . Concen Allowable Extra- 1 Allowable Total Avg, tration Limit oolated 1 Limit Count Count Fibers/ Fibers/ TWA,Fib/ for TV/A ml (1) ml (2) ml (3) <4) Mr. 1 P39 Caster Casting Dept. 121 6.05 2.22 Ceiling 2,22 Two concen- fibars/ Hr. tration 1.59 I ml.. P40 General Kelpsr Kiln Dept. 89 4.45 1.59 io 10 fibers/ u Mr. ?4l' Hand Holder Hold Dept. 514 25.7 9.16 ml. 9.16 j it f General P46 Serviceman Mold Dept. 20? 10.4 3.90 3.90 TABLE I r'on 1) Concentration of fibers/ml iif calculated on basis of sampla volume and area of manbrans filter .and microscope . field area. 1} Allowable Coiling Limit io 10 fibors/al basod on . O.S.K.A. limit as of 7/1/76. ....... ... 3) Extrapolated TWA is a mathematical calculation! TWA is Time Weighted Avorage. 4) Allowable Limit for TWA is 2 fibers/ml'based on O.S.HrA. limit as of 7/1/76. . .. ' - . mar 000854 (i i 1 Photomicrograph showirg numerous mk fT?* asimcaaxlil nfibeevrras aos wwvaxlal *a*s a few vo*f . f I *4.. ^/sjthe larger asbestos floors, Notice rrrr'TTrn. J. m.~\infringed or split end of largo fiber, I M;*;* ^ y fiksr i* 5 aiorons in siso, .! All photomicrographs aro taken at 520X magnification using phase con trast optics. MAR 000855 1.' S'1 ten 13 an exido of silicon and La tha charac-isriatic ir.".*"}o;' a great variety of minerals, including quarts, eriatobalita, Iridymits, amethyst and sand. Jt is widely used in coras for mstal c'atinj; operations, ceramics, decorative materials. Insulations, -ljar tilo, building materials and glao3. Inhalation of these partialsa c.in produce rapidly-developing (acute) or chronic silicosis a disabling lun disease. Typieally'the lung tissue reacts to the prissnee of silica particles by forming fibrous matter around the . particle. Evidence suggests that particles below one micron (onemillionth of a meter) in sise may be the most dangerous sines- they .nay penetrate deeper into the lungs in hieh concentrations (see rl^ure I). In rapidly developing silicosis, sv-ptoms ano-ar fl to 18 months after the first exposure"Chronic silicosis, the type usually i encountered in industry, generally, is produced only after years of ' silica inhalation, Tha symptoms for either type are the sams - slowly increasing difficulty in breathing under exertion. In some workers, > large masses of dense fibrous tissue develop in the upper portion of ` ths lungs, leading to severe respiratory-crippling. Tuberculosie la a frequent complication of silicosis* i Listed below is a summary of the mineral du3t (silica) limits* These requirements art fully detailed in Reference (ID* SUMMARY OP O.S.H.A. MINERAL DUST LIMITS MHei, Calculation of Allowable Limits Crystalline i Quarts (respirable)--------- 10 rvr/m3 -}&"reapirabla. quarts + 2" Quarts (total dust). to wr/a3 1* quartz * Si Cristobalitei Use i the value calculated from the formulas for quartz. Tridymitai U3e J ths value calculated from the formulas for quarts. '"lornhous. including natural diatoraaceous 0 rr/n3 (total dust). earth i ng/zP (respirable duot) vc*l dust (rosplrabla fraction less than 5JS quartz)----.----. "or core than quartz-------- Insrt or Nuisance Busti . Rsspirable Fraction------------ Total dust-------- 2.4 ns/n3 or )L0 m-/m3 respirable quartz * 2 5 Bg/aJ 15 ag/a3 Vrai 1) R-apIrable quartz dust.consists of particles which are loos than 10 microns In diameterT C) .pig milligram 3) m3 cubic meter TABLE B MAR 000856 DOST PENETRATION INTO LUNGS The following pa/res are taken direct from a dust and silica test report conducted by ROSSNAGEL & ASSOCIATES. Remember, in testing for silica, one actually performs a normal dust level test and then analyzes the catch for the silica content. In Table II it is seen that all three operators' exposure to free silica ranged from 4.1 to 10J? of the respirable dust catch. Each operator was within the calculated TLV. The final results show on Table III that two of the operators' ):rpo3ure to dust was over the TLV Threshold Limit of 10 m&al of air a.i listed in the la3t column. Note that three samples were taken on one man and two samples on each of the other two men. This waa *to avoid too high a filter collection by using ooro than one filter. Note also the proportion of the dust loading caught in the cyclone or that caught in the filter (the respirable portion). 6 MAR 000857 'i":3 data from tht ollica analysis of the filter etmplea f % i V.l "iroonal Samplers in shewn 'oelowi rrnsoriAi sampisr pp":; stltca ccNcr.-TPATrort ?: SUITS ri, S r.'.j >. ?arconal Sample ho. i location/ Activity Filter } Free Free Dust Silica Silica loading in limit Respirable Total TLV # mg Silica mg/m' Respirable Free Silica mg/m^ i 111 PS-1 ii J PS-4 i ) PS-6 1 Mr. Cupola Operator 4.1 10.0 Mr. Grinder/Ladle Mr. line. Miscel laneous jots 5.8 J 50 5*0 | 4.1 1 CABLE II .83 107 1.61 .41 OO .21 i tj See Section HI for description of NXOSH method used to determine ,i silica concentration. Silica (SiC>2) assumed to be 100JS quarts. T,y . 10 mr/n,] Tij % Respirable Quarts * 2 from A.C.G.X.H. Manual r r- i ( .M J` 7 l l k MAR 000858  . .rTRLD DATA L DP3T LOADINGS i' ** i The data from the Personal Sampler tests is presented in bolowi PERSONAL SA!-?LKR DUST LOADING TEST DATA ; J t1i .. Personal Sampler Installed on and Job Description Test Date Sam ple # Tine Flow Sam Sam Rate, ple pled, lit Vol Dust loading m/. Dust Con* Thresh centra- old tion mg/ Limit* Min ers/ utes min. ume, m3 Cy clone Fil ter Total m3 of air mg./a' Respi of air rable# if, P30 i i- ">i Mr. Cupola Operator 12/ 17 P34 P37 1 iA 1 Mr'. Grinder/Ladle 12/ P31 17 P36 43 1.86 .080 120 1.86 .223 104 1.86 .193 100 2.0 .200 111 2.0 .222 .3 W/A 1.0 2.8 1.0 S/A 4.8 4.1 5.8 8,26 *13.7 10 10 ; e Mrri ) Line, Miscel laneous jobs 12/ P32 17 P35 97 2.0 .194 1.0 W/A 5.0 97 2.0 .194 4,0 12.9 10 1 TABLE II] .0' ... * . from FEDERAL REGISTER, Vol. 36, Wo. 105, Say 29, 1971. This is allowable lir.it for 8 hr. e.uposyre of fugitive dust. It is also sometimes written as 30 m.p.p.c.f. (million particles per. cubic feet). 1 Jtecpirable concentration is based on filter catch only. This i*3 the amount of particulates which went through the inlet . cyclone and were deposited on the filter. This respirable - portion represents particulates which are believed to be "distributed as shewn in the following table taken from the . U.S. Department of Health, Education and Welfare, Public Health Service Publication #614. .. 'I 100!$ respirable' at 2 microns . 75JS respirable at 2.5 microns >f. 50J5 reopirable at 3.5 microns 25# respirable at 5 microns * Qfi respirable at 10 microns % 3olow .5 microns a major portion of the respirabies are believod to be entrained into the lung tissue and to then ; enter the blood system, alimentary canal and then be excreted. 1 * a iiinii* rmass** MAR 000859 4* Cat-ten dust occurs throughout the textile industry and affects :tr.a, z'ia:: and soft henp workr3. The greatest exposure to cotton :t gar.-'.raiiy occurs during the .carding of cotton - an operation that . *.':3 out cotton fibers and sets then parallel by drawing then between cylindors. However, machinery throughout tha cotton nill aust *' 2l:ar.aa frequently, and much e::?csura tc cottsn dust occurs thrt. `'Ala tha exact" effects of cotton dust are not known, prolongad exposure h.'.v/y air concsncrations can cauco a disabling lung disease known as bl-ssinosis. It has been determined that it is not tho cotton fibors themselves but the naterials adhering to cotton fibars, such as unwanted leaf, stem and boll trash, which when inhaled, elicit an allergic reaction or responsei Byssinosls generally advances through three recognizable stagos, Tha first is commonly called "Monday fever" and begins only after ex posure of more than 10 years. Workers develop an irritating cough, tightness of the chest and breathlessness. The attacks usually come on Monday, or after a period of absence from the plant and last only a day or soi hence the name "Monday fever". In the second stage, these symptoms extend over more days in the week and finally become permanent. If exposure to cotton dust is ended at this stage, recovery can occur. In the third stage, the tightness of the chest and labored breathing become so distressing the worker must leave the industry. The disease can progress then to chronic bronchitis and enphy3ema. Listed below is a summary of the cotton dust limits, These requireaents are fully detailed in Reference (12). SUMMARY OH COTTON PUST-PgayiRSS(ga Primary Requirements. Allowable Limit flo government code A.C.G.I.X. suggests TLV of 2 og/cubio motor TABLZ C . i i 7 MAR 000860 Now that you understand the problem, ho-* do you analyte the employees or work stations which are auspoetad to have too high a contamination level? First, Personal Gassier tests should be'made only jy a trained person. The person conducting tho tast() should *3j knowledgeable and experienced, whether they bs an ensrinter, ' industrial hygienist, chemist, etc. Ths Porsonal Samplers should be pxopcrly cleaned, calibrated and with charged-up batteries far the t-nt. The required filter (and cyclone if required) should have been 1 nrooeriy desiccated, taro weighed and sealed for uco in tho field. `fin* test i3 done with a Personal Sampler which consists of a battery operated pump, a flow regulator and a filter assembly. The major suppliers of Personal Samplers are Bendix and M.SA. MSA, Millipore an.l Bendix manufacture plain filters and Andersen 2000 provides a filter head whleh can separate the respirable and ncnrespirablo dust (tie FIGURE II). The plain filter head is used for sampling fibers 3r.-J gravimetric sampling. A filter head with an upstream vsrticle elutriator is used for cotton sampling. The vertical elutriators are approximately 3" dia. and 4 ft. long. The reason for not using a plain filter when sampling for silica and cotton dust is that from a standpoint of health, only that portion of She du3t which is deposited deep in.the respiratory system is hornii:l (see FIGURE I for liing penetration). Therefore, NI03H has divided the contamination levels into respirable and ncnrespirablo categories. Tin r?5olrable contaminants are < 10 r.lcrm3 for S5.0g only. Those are S.TTcontaminants which remain in the lungs. To distinguish between respirable and nonrespirable contaminants^ a cyclone must be used upstream of the filter in the Perse as shown in FIGURE IV. ROSSNAGEL- k ASSOCIATES also makes* Andersen 2000 Mini-Sampler (see FIGURE Zl) head on certain for two reasons. One reason is.the Mini-Sampler it imalltr other filter head used for dust and the second is that It dli respirable dust into 5 site categories# This is important which area of ths lungs is affected and for selecting control A nummary of ths filter types Is shown in Table D on ths follow ing page. b t I 10 MAR 000861 SUGARY 0? 7I1TSR ft S77C1AL TES? REQUIREMENTS intamlnant . Subatance 1 Filter Types* Asbestos Fiber 1. Cellulose Membrane (recommended by NIOSH)# 2. FVC (recommended by MSA) Siso aa 37 37 Micron Size a Special Teat Requirements Silica (Free) 1. Cellulose Membrane (for colorimetric nnalyols) 2. FVC (for X-ray diffraction) 37 37 5 Cyclone required Dust. Me tile or Par ticulates 1. Cellulose Membrane 2. FVC 3* Andersen Mini-Sampler 37 37 N/A .8 Separates catch into 5 cate goric:! Cotton Suat 1. Cellulose Membrane (for fiber sizing use) 2. FVC (for gravimetric U3e) 37 37 5 Vertical Elutriator required TA3LZ 0 * Tha use of the proper type of filter la very critical when optical examination Is performed since the filter itself must be cleared by a specific clearing solution. Seme filters used in sampling, rueh aa Triacetate. Vinyl and FVC, have a recommended clearing 'Tolution. However, the clarity is sharpest using the eellulose r.nirwe filter. A different clearing solution is uaod for each .'.V.ltjr typo. R03S*fAG2L a ASSOCIATES his found that Cellulose :'merino filtora are boat suitod for optical analyoia. Cellulose Membrane filter is used whenever *cltaring" (dissolving i . of the filter) is required for microscopic analysis. l1 I **^ #**.* 11 4 I' IWOUW "**.%# MAR 000862 Extreme care must bo utilised during the actual teat to insure '.^curate results.. The sampling period should be from 2-8 hrs.'* depending cn circumstances. 1* less'than o hrs. of testing is done, the TWA calculation is corrected to an 8 hr. base. There is some -confusion on .'bather the actual sampling period should include time away from the work station for lunch and breaks. We suggest the following guidelines. If an operator is exposed to severe dU3t, for example, only during un loading of bags for one hour at the start of the shift, then it would be an overly severe test to only conduct sampling on him during that time (unless a "worst ease" test is desired). The time sampled should reflect his normal operations, preferably for at least 4 hours. The photos in the attached Procedure #113 show the preferred loca tion of tne filter on the shirt lapel near the nose. The MlnlSamnlcr or filter head la ooinr-d downward ro nn to simulate the none and not collect nartlcuiaten railinr from gravity effects, 'the flow rate should be checked periodically during the test since it can change due to the filter loading or the battery discharging. The person being' tested should also be watched to Insure that he does not do anything which could affect the accuracy of the test. Persons wearing the equip ment have frequently been caught taping the filter with a dirty glov* to get a higher reading for vindictive reasons. The test pump is usually attached to the belt in back of the operator as shown in the photos. | [ ! The sampling flow rates should be set, according to OSKA sampling data sheets, for 1.0 to 2.5 liters/min. or as limited by the Personal Sam- > pier pump capability. The person conducting the test should check the flow rate at least every half hour and more frequently if necessary. However, this is only the first half of the test, ROSSNAGEL * ASSOCIATES can provide the samplers or you can buy them and do this part of the test in your own plant. The second important part of the test occurs when you end the test, shut off the pump, replace tne cover on the filter and then face the lnb analysts. The filters used in collec tion of cotton dust and silica dust are dried in a desiccator and prewoighed to .1 mg. before ths test and then dried in' a desiccator and weighed again after the test to determine the weight of dust collected and then divided by the oample volume to arrive at a ooneentration level which is compared to tho limits in Table B ft C. j *- The attached Procedure #113# "Checklist for O.S.H.A. Personal "-:nling,".details the other important considerations to be taken to arly conduct such tests. - . 1 * campling as low as 15 minutes is acceptable for asbeetoa - 12 MAR 000863 MAR 000864 The final test raport should ineluda copies of all th original *ild data and calculation shoots an yoll as backup photomicrographs. JCh.VGEL k ASSOCIATES is able to'laout all its O.S.H.A. tost retorts `hin a maximum of 10 working days* If you have an inplant dust or fiber problem it is to your advantage 9 take stops to determine its severity before O.S.H.A.* the union or a .jjal olaim requires it* It is your mlnlwu|n responsibility* . jrancfisx (1) General Industry Guide for Applying Safety k Health Standards* O.S.H.A. 2072. (2) Tarsst Health Hazards, O.S.H.A. 2051. { (3) What Every Employer Heeds to Know About O.S.H.A. Record Keeping* r. O.S.H.A. Retort 412. (:0 Record Keeping Requirements under the Williams-Steiger Occupational ' Safety k Health Act of 1970. ; (j) Federal Register* Vol* 37* No. 202* dated Oct. 18* 1972* Fart II. | ; >) FederalRegister* Vol. 37* dated June 7* 1972* i ;?) FederalRegister* Vol. 39* No. 125* dated June 27* 1974* Fart II V\) FederalRegister* Vol. 40* No. 197* dated Oct. 9* 1975* Fart II v?) N.I.O.S.H. Manual of Analytical Methods. 1974 l ;10) N.I.O.S.H. Criteria Document - "Occupational Exposure to Asbestos"* " 1972 (11) N.I.O.S.H. Criteria Document - "Occupational Exposure to Crystalline k Silica", 1974 (12) N.I.O.S.H. Criteria Document - "Occupational Exposure to Cotton Dust", 1974 , MAR 000865 tnfinttting 4 Itthug CaiuutUntl 1ff IT. TO CH1MT Mill. N. J. CIOS} (404104.4440 ______ _ J Oi.nUm 330 ARIZONA AVI.. H. (i ATLANTA, OA. JSI9T . M04I 111.4141 PROCEDURE *1173 c-rseyLTS? pqs o. s. m. a. personal saitpltxc 3/22/76 A. lata and Test Eouloment Preparation 1. Determine which type of filters will tae usedi j. a. Cyclone A Preweighed Filtersi Two types .depending on off. Sizei 37 ma Kfg.i Bendlx. MSA ta, Filter in Plastic Holder Sizei37 ma Membrane Filter Mfg.iMillipore* Celman e. Andersen Particle Size Distribution Filter Head 5 plates plus final filter FilteriType A Class Fiber 25 ma 2. Verify the Personal Samplers are properly calibrated { J: Desiccate filters for at least 24 hours before weighing. Record weights on RA Fora #26 and. keep weighed reference filter; in doslocator. * i I: Get all batteries charged from power packs. ' Check calibration of unite for filter to be used. B. On Day of Test 1. 2. 3. .., 4. Start Events Log Sheet on RA Form #28 upon arrival and then contact operating personnel at test location. Just prior to start of test, place pumps vertically and turn on and adjust flow rate for test. Use required flow' rate. Filter head must be attached for this adjustment. Carefully place equipment on person to be sampled. Be sure to have filter pointing down and close to nose of operator, see attached photo page for proper placement. Check each individual wearing a filter and flow, rate at least every 15 minutes. Record each time an Individual's, pump is turned on or off. such as for.lunch or leaving the plant. 3. 7ort Test Lab Work 1. Dry filters in oven if gravinitrie analysis la to be done. 2. Desiccate filters or sampler plates for at least 24 hours bofore weighing. l:> Weigh and record on RA Fora #26. 'Keep samples in laminar flow booth in particle size lab. 0. Microscopic Examination 1. Follow Micrcn Size Distribution Analysis Procedure #114 or . O.S.H.A. Fiber Statistical Microscopic Sampling Procedure #1-5 2 Save all filter samples in proper labeled and dated case. 3. Take at least one typical photomicrograph of a group of if customer requires Particlo Size Distribution analysis. .4 .15 ^0 * --- irftd. MAR 000866 MAR 000867