Exposure Limits: TWA: 300 (ppm) from ACGIH (TLV) [United States] TWA: 300 (ppm) from OSHA (PEL) [United States] TWA: 1050 (mg/m3) from OSHA (PEL) [United States] TWA: 100 STEL: 300 (ppm) [United Kingdom (UK)] TWA: 350 STEL: 1050 (mg/m3) [United Kingdom (UK)]Consult local authorities for acceptable exposure limits.