Document V3ww0gbazdgXEORgvQqMgGzzj

Biochemical Research Laboratory The Dow Chemical Company /70 A SURVEY AND EVALUATION OF PIPE COVERERS' EXPOSURES TO DUSTS FROM ASBESTOS CONTAINING INSULATION MATERIALS ENCOUNTERED DURING ROUTINE PIPE COVERING OPERATIONS WITHIN THE MIDLAND LOCATION OF THE DOW CHEMICAL COMPANY File: Date: By: T2.1-1-64 ^H) March 21, 1969 R. A. DeGesero Signed Checked Date PROBLEM 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. ST00006 I 7 RESTRICTED: for use within The Dow Chemical Company only. 2 3- Men are encountering time-weighted exposures to dusts-from -insulation materials containing asbestos exceeding the proposed ~TLV o'f 2 mppcf. 4. 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. RECOMMENDATION'S 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. ST00006I 8 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 during sampling, estimates provided by an industrial engineering time study, and a questionnaire filled out by the pipe coverers. A sample questionnair 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 (5 day) per operation and material, and are listed in Table 1. Thirty-two 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: ST0P00620 Table 1. TIME-WEIGHTED EXPOSURES OF PIPE COVERERS TO DUSTS FROM ASBESTOS CONTAINING MATERIALS Operations Materials # Day Concentrations (mppcf) Mean Range Time-weight Factor: Asbestos Remove Mix Cut Apply Air cell Kaylo Mag oxide Fiberglas No. 1 Plus Armentite Superpower Air cell Kaylo Fiberglas Others Air cell Kaylo Fiberglas Others No. 1 Plus Armentite/ Superpower 1.2 1.6 0.2 2.0 1.6 0.1 0.3 5-9 8.3 2.2 0.6 15.3 19.9 4.5 2.5 4.3 2.4 11.4 11.2 2.8 13.7 13.4 5-5 34.9 3-0 11.7 1-7 -- 5-7 5-7 2.4 -- 9*5 2.1 0.3-24.9 3-7-20.5 1.8-4.6 1.2-33-7 2.2-30-5 2.7-13.5 19-6-6.14 0.6-6.2 4.9-23.1 0.8-2.5 -- 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 - -1 -- 0.901 1.123 -- ___ 0.451 0.050 ST0000623 Clean up removed covers Stocking ; get new covers Move to Job, set up Breaks, lavatory 3-2 2.0 5-0 15.0 " 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 8 n n n 0 0 I ^i Table 1. CONTINUED Operations Materials Remove Mix Cut Apply Air cell Kaylo Fiberglas Others No. 1 Plus Armentite Superpower Air cell Kaylo Fiberglas Others Air cell Kaylo Fiberglas Others No. 1 Plus Armentite/ Superpower Clean up removed covers Stocking ; get new covers Mo ve to job, set up Breaks, lavatory # Day Concentrations (mppcf) Mean Range Time-weight Factor: Asbestos 1.2 1.5 2.0 0.2 1.5 0.1 0.3 5-9 8.3 2.2 0.5 15.3 19 - 4.5 2.6 4.3 2.4 5-2 9-0 10.0 -- 9-6 17.0 21.3 2-5 9-4 2-5 1.5 9.2 - aw -- 1.4 6-2 5-1-5-2 3.6-14.0 5-5-20.2 --- 5-9-12.5 14.1-21.6 13.1-25.4 O.9-3.4 6.3-7.4 I.4-3.8 -- 0.3-3-5 1.9-17.9 1.6-6.7 -- 0.3-2.3 3.5-7-9 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 3.5 2.4-24.6 1.0 0.1-2.3 2 . C 1.4-2.9 1.4 0.1-3.9 0.255 0.020 0.100 0.210 Time-weighted exposure to asbestos containing dusts (outdoor) in ir.ppcf = 4.2 T a b le 2 . MATERIALS MOST COMMONLY USED FOR FIR ST TEN MONTHS OF 1968 P rH H eC*9 aa O 0 0 0 rH 0 CJ 0in CM m 039 CU (-1 E X >Q E- 09 -P E 0) CC OM -P rH 05 O Q. o 09 CJ O 4-> cu 09 <c rH O oo O3 3 rH <0 E E CU 09 c c -rH SR $in 0 o> rH 'Sc--R $ i$ O0 cu CM 0 C** 00 W 2 0 'SnR CVJ CO aOo SinR O0 Oin CM 09 3 O a E 09 0 <u -P <0 CO 0 SR'-c O rH O hH rH 09 09 09 09 3 -P 0 <0 CU O O tH CO r-l 0 0p9 -p cO H 3 93 -rt 0 "SR-* in co cn 0 >oR i1n Q> (U cu >> > rH rH rH <u 09 09 05 09 <U CU <D 0 .C T9 T9 <c <C < 09 09 EE 09 09 >> c CJ rO> 09 E 09 > O CJ ,,__ -- >> ec cu E CaO 0) 3 ,,--V E r--H p >1 O rH 0 c CJ *H co Oh cao 2 > c ---- >1 >5 co 09 aE -- bo c rH c E 3 E Ed CO CO O C CO O O . S l 2 03 r0 CU C T9 C w P3 09 3 0c '-C-O--- O ^0 09 E 4-9 0 CJ CJ O 1 09 >> '---- 09 SR C 09 E CO CJ in 00 -- ,-- 3 O ---- cu 3 CU (U CO 09 >> 09 rH 3 -P E rH T9 C CO CO c CU CM, rH aO E H O -p a cE rH 09 C9 rH CO xa O rH b0 E, T9 CO E E" O 2 cu a cu 0 EO 3 Eh CO < E H < O 2c6oC0 CU rH fc 09 E 09 > C c ----to c rH c E O O 1 09 G 09 3 --O- O rH >> co id OO O O o o CP ro cr * OFFICE COPY Biochemical Research Laboratory The Dow Chemical Company /oyo 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: T2.1-1-54 (H) March 21, 1969 R. A. DeGesero Signed Checked PROBLEM 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. ST00006 I 7 RESTRICTED: for use within The Dow Chemical Company only. 3 PRESENTATION OF DATA Indoor pipe covering operations were surveyed from 12/24/68 to 1/22/59. Outdoor pipe covering operations were surveyed from 2/20/69 to 3/5/69. Air samples to account for "miscellaneous" portions of the pipe covering functions were obtained from 3/1/59 to 3/5/59- 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 oust 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.^- mppcf (mean particles/quarter field) x 4 x 1000 x sample volume liters (pump flow) x minutes x 3-51 x 10~2 ---- min. liter ST0000619 1 Patty, P. A., INDUSTRIAL HYGIENE AND TOXICOLOGY, Vol. I. Second Revised Edition, p. 198. o 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 k.9 mppcf (indoor operations) and k.2 mppcf (outdoor operations). ST0000622 8 n n n n nO I^ Table 1. CONTINUED Operations Materials Remove Mix Cut Apply Air cell Kaylo Fiberglas Others No. 1 Plus Arme.ntite Superpower Air cell Kaylo Fiberglas Others Air cell Kaylo Fiberglas Others No. 1 Plus Armentite/ Superpower Clean up removed covers Stocking; get new covers Move to job, set up Breaks, lavatory % Day Concentrations (mppcf) Mean Range Time-weight Factor: Asbestos 1.2 1.5 2.0 0.2 1.5 0.1 0.8 5-9 8.3 2.2 0.5 15-3 19 -9 4.5 2.6 4.5 2.A 5-2 9.0 10.0 5.1-5-2 3-6-14.0 5-5-20.2 9.6 17.0 21.3 2.5 9.4 2.5 5.9-12.5 14.1-21.6 13.1-25.4 0.9-3.4 6.3-7.4 1.4-3.8 1.5 0.3-3.5 9~ .2 1.9-17.9 1.6-6.7 1.4 0.3-2.3 5-2 30-7-9 0.062 0.144 0.154 0.017 0.148 0.827 0.237 I.83I 0.067 0.125 ST X- * 3-0 2.0 5-0 15-0 3.5 2.4-24.6 1.0 0.1-2.3 2 . C 1.4-2.9 1.4 0.1-3.9 0.255 0.020 0.100 0.210 Time-weighted exposure to asbestos containing dusts (outdoor) in mppcf = 4.2 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 proceeds acceptance of proposed TLV's. In 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. STQ000625