Document reZVrkyebyEwnVRRJ80ge16GE

BASF Wyandotte Corporation BASF to j. J. Ronayne, M.D -----INTER-OFFICE MEMORANDUM date February 11, 1972 from Warren McNab subject copies PEArmstrong, CWAxce, ECBurckbardt, reference RSRoth Asbestos Dust in Workroom Air, ' W-2 and Geismar Data are at hand on asbestos samples taken in December, 1971. Samples were collected in personnel samplers which employees wore in the breathing zone. The samples were counted by The Environmental Health Labs, of Farmington, Michigan. The emergency standard for asbestos in air, issued December 7, 1971, lists the permissible exposure (TWAE) as 5 fibers per ml,more than 5 microns in length, and designates the equipment to be used for counting. The TLV is not given in millions of particles per cubic foot (mppcf). However, the formula mppcf X 35.3 = particles per ml is suggested. On this basis, the TLV is equal to 0.142 mppcf. We would appear to be greatly in excess of this as the data are reported. Sample A B C D E F Plant W2 W2 W2 G3 G1 G1 Activity 3 cathodes built No " 3" 1" 1" 2" MPPCF 7.8 2.3 6.1 2.9 9.7 7.4 There is good reason to believe, however, that these counts do not offer a true gauge of worker exposure to asbestos, considering the comments of the EHL analyst, quoted below verbatim: `.'There were no discernible fibers in the counting areas although some fibers were observed outside of the areas. This is not surprising if the asbestos is Chrysotile because the fiber size (diameter) is often below the resolution of light microscopy." This tends to emphasize the difficulty of asbestos counts, but does not provide reasn for not sampling. It might be well to split samples between other laboratories in the future. RWM/c F 48 B~-'* BASF Wyandotte Corporation ----------------------------------------------------------------------------------------INTER-OFFICE MEMORANDUM j.io J. Ronayne, M.D. date February 11, 1972 from Warren McNab subject copies PfArmstrong, CWAxce, ECBurckhardt, RSRoth reference Asbestos Dust in Workroom Air, W-2 and Geismar Data are at band on asbestos samples taken in December, 1971. Samples were collected in personnel samplers which employees wore in the breathing zone. The samples were counted by The Environmental Health Labs, of Farmington, Michigan. The emergency standard for asbestos in air, issued December 7, 1971, lists the permissible exposure (TWAE) as 5 fibers per ml, mare than 5 microns in length, and designates the equipment to be used for counting. The TLV is not given in millions of particles per cubic foot (mppcf). However, the formula mppcf x 35.3 particles per ml is suggested. On this basis, the TLV is equal to 0.142 mppcf. We would appear to be greatly in excess of this as the data are reported. Sample A B C D E F Plant W2 W2 W2 G3 G1 G1 Activity 3 cathodes built Mo " `" 3" " 1" " 1" " 2" MPPCF ' 7.8 2.3 6.1 2.9 9.7 7.4 There is good reason to believe, however, that these counts do not offer a true gauge of worker exposure to asbestos, considering the comments of the EHL analyst, quoted below verbatim: ``There were no discernible fibers in the counting areas although some fibers were observed outside of the areas. This is not surprising if the asbestos is Chrysotile because the fiber size (diameter) is often below the resolution of light microscopy." This tends to emphasize the difficulty of asbestos counts, but does not provide reason for not sampling. It might be well to split samples between other laboratories in the future. RWM/c e 46 e