Document n5djRyXBbyRZnzydb8vJydMz

Tbo three oamplos collected at Dice Brake Preform showed an unusual reduction in airborne fibers. Only one of the units (Uo. 3) has been redesigned to any e>rtcnt and would not account for the dramatic decline et all units to 0.43# 0.8, and 0.53 fibcro/ml from previous levels above the five fiber limit. Since the asbestos hoppers above the preform machines were not manually filled at any time during the sampling periods, the omission could account for the reduced exposure. Heavy concentrations of airborne asbestos are generated during this phase of the operation. One other location. Disc Brake Inspection, was found to be above the 2 fiber limit. Inspection, exposures are generally caused bv dust adhering to the surface of the brake pads. Steps should be taken to reduce this exposure eitner through procleaning of the pads or provision of adequate exhaust ventilation. All collected asbestos samples were also analyzed for airborne lead. As indicated in Appendix 2, only two of the samples reached or exceeded the Threshold Limit Value of 0.15 mc/tP. The locations involved included Blok Preform Ho. 15 ana Blok Preform No. 5. Since these were short-term samples, the listed values (Sample 19, .149 ana sample 25, .197 mg/L-iP) do not represent time weighted concentrations or averaging over fin 8 hour workday. The only inference that can be drawn from the values is that they may be representative of the air borne lead concentrations present during any other short term period daring the 8 hour workday. This may or may not be the case. Blok Preform Ho. 5, which was sampled twice, skewed the aforementioned short term level of .197 mg/N^ and an earlier leval of 0.137 rngAi3 for an average of 0.167 pg/[4^. Since both exposure locations were Blok Preform units, it is apparent that further collection system improvements are needed. Personal samples of printing ink3 were taken at Blck Finish Printer No. 2, Strip Finish Hand Printer No. 2, and Strip Finish Printer l-tachine No. 10. As. anticipated, airborne con centrations of the methyl ethyl ketone solvent in the different inks were minimal, ranging from 2.17 rag/l-l^ to 59.23 rvg/bl^ versus the Threshold Limit Value of 5S0 mg/M-*. From the stand point of a fire and explosion hazard, ambient concentrations ara not a problem since the Lower Explosive Limit is over 53,000 mg/l-i-* in air. However, smoking and open flames in the immediate vicinity of the printing units should be prohibited. 2- -