Document jm45azD6Zagwenr8DpDGdjbkO

OFFICE COPY Biochemical Research laboratory The Dow Chemical Company to 70 A SURVEY AND EVALUATION OP PIPE COVERERS' EXPOSURES TO DUSTS PROM ASBESTOS CONTAINING INSULATION MATERIALS ENCOUNTERED DURING ROUTINE PIPE COVERING OPERATIONS WITHIN THE MIDLAND LOCATION OP THE DOW CHEMICAL COMPANY Pile: Date: By: T2.1-1-64 March 21, 19^9 Signed Checked PROBIZM Supervision requested that the Environmental Research Laboratory survey and evaluate current levels of pipe coverer's exposures to dusts from asbestos-containing Insulation materials commonly used within the Midland location. CONCLUSIONS 1. The present Threshold Limit Value (TLV) for asbestos of 5 mppcf will remain in force until 1971* Barring information to the contrary, the TLV will then be lowered to 2 mppcf (million particles per cubic foot). 2. Men are encountering time-weighted exposures to dusts from insulation materials containing asbestos approaching but not exceeding the present TLV of 5 mppcf. CONFIDENTIAL RESTRICTED: for use within Thd Dow Chemical Company only. * 2 3. Men are encountering time-weighted exposures to dusts from insulation materials containing asbestos exceeding the proposed TLV of 2 mppcf. ii. If exposures are to be reduced to within tentatively accepted levels (2 mppcf) either the use of asbestos-containing insulation materials must cease, or pipe coverers must be protected through effective use of approved respiratory devices and/or local ventilation. RECOMMENDATIONS 1. Pipe coverers should be educated to the true hazards associated with the several types of insulating materials they presently use. 2. Pipe coverers should be made aware of the several ways of protecting themselves during unavoidable, potential exposures to dusts containing substances known to be highly toxic, such as asbestos. 3. In the future, pipe coverers should be educated to the true hazards associated with any new types of insulation materials to be used, prior to use. 3 PRESENTATION OP DATA Indoor pipe covering operations were surveyed from 12/24/53 to 1/22/69* Outdoor pipe covering operations were surveyed from 2/20/59 to 3/5/69* Air samples to account for "miscellaneous" i portions of the pipe covering functions were obtained from 3/l/o9 to 3/5/69* Sampling and Analysis A total of 141 breathing zone samples were collected in midget impingers and analyzed employing standard light field microscopy techniques for determining dust concentrations from insulating materials containing asbestos- Concentrations found in samples were expressed in terms of millions of particles per cubic foot of air (mppcf), according to the following formula.1 t mppcf (mean particles/quarter field) x 4 x 1000 x sample volume -1^er-a (pump flow) x minutes x 3-51 x 10"2 ---- min. liter UOU U u 1Patty, F. A., INDUSTRIAL HYGIENE AND TOXICOLOGY, Vol. I. Second Revised Edition, ?. 193* t n f m n n i <; 4 The means and ranges of concentrations found during sampling are listed in Table 1. Job Analysis and Description An environmental Job analysis provides an estimate of the frequency and duration of men's exposures to dust concentrations, surveyed. The Job analysis expresses as per cent of the day day) the probable time distribution of pipe covering operations, averaged over several months. On any given day the pipe coverer's routines can be expected to vary from the estimate. The Job analysis reconciled input from discussions with pipe coverers and supervision, observations duri.ig sampling, estimates provided by an industrial engineering time study, and a luestionnalre filled out by the pipe coverers. A sample questionnaire is found on page i of the Appendix. The questionnaire requested that men estimate the per cent of time per day they spent working with the most common insulating materials. Men's averages were converted into ratios of time spent ( day) per operation and material, and are listed in Table 1. Thirtytwo per cent (26 men) of the Midland coverers responded. Responses concerning rarely used materials (e.g., cork, styrofoam, some putty adhesives, etc.) were set aside. Other information furnished by the coverers included: i \t 5 Average age: Years covering within Dow: Years covering outside Dow: Wear respirator? Which material(s) are the dustiest? 40 years 18 0 Yes: IT men ; No: ' men Kaylo: Piberglas: High temp.: Superpower: Mag oxide: Aircell: 16 men 14 men 11 men 6 men 2 men 2 men n ifio n n ic Time-Weighting Exposures Men's exposures to dusts from asbestos-containing insulation materials were estimated by "time-weighting." The exposure frequency and duration (* day) to each material is multiplied by the mean concentration in air of each material, giving a set of "time-weighted factors." The "factors" (product of * day x mean concentration) are then added up for the eight hour day: 100* Time-Weighted Exposure * i 0 * day x concentration 100* or, * (time-weight factors) 1 0 6 Table 1 lists the % day, mean concentrations found, time-weighted factors and ranges for each material encountered in the listed operations. The time-weighted exposures to dusts from asbestos containing materials were 4.9 mppcf (indoor operations) and 4.2 mppcf (outdoor operations). t 7 Table 1. TIME-WEIGHTED EXPOSURES OP PIPE COVERERS TO DUSTS FROM ASBESTOS CONTAINING MATERIALS Ooerations Materials % Day Concentratlens (mppcf) Mean Range Time-weight Factor: Asbestos Remove Mix Cut Apply Air cell Kaylo Mag oxide Plberglas No. 1 Plus Annentlte Superpower Air cell Kaylo Plberglas Others Air cell Kaylo Plberglas Others No. 1 Plus Armentlte/ Superpower 1.2 1.6 0.2 2.0 1.6 0.1 0.8 CO 8.8 2.2 0.6 15-8 19-9 *5 2.6 4.8 2.4 11.4 11.2 2.8 13.7 13.4 9.6 34.9 3.0 11.7 1.7 -- 5.7 5.7 2.4 ._ 9.6 2.1 0.3-24.9 3.7-20.5 1. o-4 6 1.2-33-7 2.2-30.5 2.7-13.5 19.6-6.14 0.6-6.2 4.9-23.1 0.8-2.6 --- 0.2-16.4 0.4-22.3 1.2-3.8 ... 1.1-39.5 0.9-3.9 0.137 0.179 0.006 -- 0.219 0.010 -- 0.177 1.030 --- -- 0.901 1.123 ... ... 0.461 0.050 Clean up removed covers Stocking; get new covers Move to job* set up Breaks* lavatory 3.0 2.0 5.0 15.0 8.5 2.4-24.5 1.0 0.1-2.3 2.0 1.4-2.9 1.4 0.1-3.9 0.255 0.020 0.100 0.201 Time-weighted exposure to asbestos containing dusts (Indoor) in mppcf 6 Table 1. CONTINUED Operations Materials Remove Mix Cut Apply Air cell Kaylo Flberglas Others No. 1 Plus Armentlte Superpower Air cell Kaylo Flberglas Others Air cell Kaylo Flberglas Others No. 1 Plus Armentlte/ Superpower Clean up removed covers Stocking ; get new covers Move to job, set up Breaks, lavatory % Day 1.2 1.6 2.0 0.2 1.6 0.1 0.8 CO 8.8 2.2 0.6 15.8 19.9 * 2.6 4.8 2.4 Concentrations (mppcf) Mean Range 5.2 9.0 10.0 ' 9.6 17.0 21.3 2.5 9-4 2.5 -- 1.5 9.2 3.6 1.4 5.2 5-1-5.2 3.6-14.0 5-5-20.2 --- 5-9-12.5 14.1-21.6 13.1-25*4 0.9-3-4 6.3-7 1.4-3.8 0.3-3-5 1.9-17.9 1.6-6.7 -- 0.3-2-3 3.5-7-9 Time-weight Factor: Asbestos 0.062 0.144 0.154 0.017 0.148 0.827 --- --- 0.237 1.831 --- 0.067 0.125 3-0 2.0 5.0 15.0 8.5 1.0 2.0 1.4 2.4-24.6 0.1-2.3 1.4-2.9 0.1-3.9 0.255 0.020 0.100 0.210 Time-weighted exposure to asbestos containing dusts (outdoor) m mppcf w u, 2 IuuouI J 9 Threshold Limit Values (TLV) A TLV describes that time-weighted concentration of a material to which men can be repeatedly exposed for eight hours with no adverse effects on health. A TLV indicates a mean concentration which can be exceeded, provided there are corresponding exposures lower than the TLV* At present the TLV for dust containing asbestos is 5 mppcf using standard light microscopy techniques. Based on best current information, the proposed TLV of 2 mppcf would provide better protection. A two year trial period preceeds acceptance of proposed TLV's. Tn 1971, 2 mppcf will be the TLV for asbestos, unless better information during the interim casts doubt upon the proposed figure. This report evaluated current exposures using the proposed standard of 2 mppcf if the material in question had even trace (<5) asbestos content. Manufacturers were consulted regarding the composition of the insulating product(s) found in common usage. The following table lists these materials and the per cent asbestos plus the appropriate TLV for that material. t f i l T a b le 2 . MATERIALS MOST COMMONLY USED FOR FIR S T TEN MONTHS OF 1968 .0 B<- S 0 *j a a *pDH^EP O CM O O 0 CM 20 in 09 SS OO % CM CM Oo d CM in oo X <0 u eO Mc0 0 oO Bo 1*0 0 i 0 K ev os $ s in1 v $ s I $ CM * ns 2ta- 0 g 00 O 9 4C0JD 00O -00H O0 * 0E *HD 3 0 9\ 0 * * I 000 >>> V* 000 00 0 JZ JS O 0 *o s < < 00 u t00 >> O0 O0 0 U 0 > O O & 3. 6 >* O eO X > e >c% >* 0a t tcHo c U I a s O1 E o0 o 0 V s 0n 9 0c X-- o0 co >> 0 c1ino* 0 c 0 X 1 4* o 0x s 0 0 EO l* 0a 9 2 8. C t. 0o "o 0 0 wsH* 2 01 MO H tuo 0 i 2 CO < 0 f* 0 > 0 0 tco H cu 0 o1 0 c 0 poH 9* C c V c <: c 11 DISCUSSION Men were found to be working almost exclusively with asbestos-containing materials. Their time-weighted exposures to jdusts from the asbestos-containing materials were in excess of the proposed TLV of 2.0 mppcf and barely under the present TLV of 5 mppcf. Steps should be taken to lower the time-weighted exposures to within proposed acceptable limits. Several means of reducing the time-weighted exposures are apparent! 1. Cease using asbestos-containing materials. If use of asbestoscontaining materials was stopped, exposures would be reduced to acceptable levels, even though some low-level exposure would be experienced until presently installed coverings have been replaced due to natural attrition. 2. Effective use of approved respiratory devices. Respiratory protection Is practical for jobs which are of short duration and Infrequent occurrence. It can be seen from Table 1 that jobs requiring respiratory protection are neither infrequent nor of short duration. Men encounter greatest exposures during the cutting and applying of Air cell and Kaylo. These two operations are done for 500 of the day -- sometimes 1000 of the day. Many other operations listed In Table 1 could require t 1 12 use of respiratory devices. Attempts to lower exposures to 2 mppcf by using respirators seem futile. 3 tJse local ventilation. This method would be effective if the ventilation could be kept close to the dust source. iPipe coverera* work routines make this difficult; e.g., working aloft, or In cramped areas. Zn the event new types of covering materials are used, men should be Instructed regarding the toxic properties of the materials and the hazards associated with using the material. Protective measures to prevent or lower undesirable but unavoidable exposures to the material should be well understood. Any education effort must precede or be concurrent with first usage of new materials. During this survey, most men voiced strong objection to flberglas, asserting that flberglas insulation materials were far more hazardous than asbestos insulation materials. This contention is not supported by 25 years available field experience and independent laboratory testing on flberglas. The Environmental Research Laboratory win survey and evaluate upon request any proposed types of insulating materials and relate their usage to the health hazards associated with these materials. c c c c < t APPENDIX ENVIRONMENTAL RESEARCH QUESTIONNAIRE Please answer the following questions as completely as possible, using average estimates. Name _ Man # ____ ____________ Age Number of years with Dow . Number of years covering pipe _ . Do you war a respirator? Yes __ No __ What make ________ If yes, list those operations during which you wear a respirator ___ What per cent of the day is this? _ Have you covered pipe or handled covering materials outside of Dow? Yes __ No ____ If yes, how long did you cover pipe? Answer the following if they apply to vou. How much time per day do you* (a) Remove old fiberglaa covers? (b) Remove other types of covers? List other types you remove* ^__________ (c) Mix "plus one" webbers? Other adhesives? (d) Use power saws? List %faat you cut with a power saws (e) Use hand saws? List what you cut with a power aawt How much time per day do you* (a) Work with "air cell" _ (b) Work with "Kavlo" ,, _ (c) Work with "Hi-temp" <d) Work with fiberglaa Which job(s) do you consider most dusty? How often do you do this job(s)? b lU U b b Ib i PLEASE RETURN FILLED OUT FORM TO* LURRY WARREN, 189 BUILDING -1- 13 unit index Pipe covering operations were surveyed and evaluated. Men deceived time-weighted exposures to asbestos near the present Threshold Limit Value of 5 mppcf and in excess of the tentatively proposed Threshold Limit Value of 2 mppcf. Steps should be taken to reduce exposures to the proposed new standard* DISTRIBUTION L. Warren, Field Service Unit #6, 189 Building R. Wood, Field Service Unit #11, 49 Building H. Ahlich, Field Service Unit #2, 759 Building B. VanderKlipp, Distribution, 572 Building T. J. Madden, Field Service Unit #10, 222 Building (6) J. Bradley, Plastic Prod. Maintenance, 433A Building B. B. Holder, M.D., Medical Department, 607 Building H. L. Gordon, M.D., Corporate Medical Department, 2030 ARC D. B. Morse, Safety Department, 401 Building S. M. MacCutcheon, Safety and Loss Prevention, 2030 ARC R. J. House, Division Accounting Staff, 256 Building L. Anderson, Plant Engineering, 800 Building ^ *t(uor^ f -- l**>*4~ 70 G K'ramer, Corp. - o-cbo t'X`76 RADrsjl M -f Spruce O /J. hi&ui**) (?67 6 I89001S o