The Occupational Health and Safety Regulation provides that, except as otherwise determined by WorkSafeBC, an employer must ensure no worker is exposed to a substance exceeding the Threshold Limit Values (TLVs) prescribed by the American Conference of Governmental Industrial Hygienists (ACGIH). …When WorkSafeBC adopts the new or revised ACGIH TLVs as regulatory exposure limits for chemical substances, these exposure limits are referred to as B.C. Exposure Limits (ELs). An EL is the maximum allowed airborne concentration for a chemical substance for which it is believed that nearly all workers may be exposed over a working lifetime and experience no adverse health effects. …The following substances with new or revised TLVs for 2025 have been added to the Table of Exposure Limits for Excluded Substances in Prevention Manual Item OHS Policy R5.48-1: Copper naphthenate, Inhalable Fraction & Vapour; Nicotine; and Nicotine, Inhalable Fraction & Vapour.