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ppm mg/m3 ppm mg/m33 (Threshold Limit ValueTLV)

(Threshold Limit ValueTLV)

TLV-TWA: time weighted average concentration 85(hypersusceptibility)(2) TLV-STEL: short term exposure limit, 1.15 2. 3.1 (3) TLV-C: ceiling exposure limit

(time-weighted average)(Permissible Exposure LimitPEL) 100 ppm. 2 hours exposure at 150 ppm2 hours exposure at 75 ppm4 hours exposure at 50 ppm.TWA = (150)(2) + (75)(2) + (50)(4) = 81.25 ppm 881.25 ppm 200 g/beeLC50