ACGIH Board Ratifies 2025 TLVs, BEIs

ACGIH’s board of directors has ratified the 2025 Threshold Limit Values (TLVs) for chemical substances and physical agents and Biological Exposure Indices, or BEIs. According to ACGIH’s substances and agents listing, the board adopted TLVs for chemical substances including copper naphthenate and nicotine.

The board has also approved recommendations for additions to the Notice of Intended Changes list. The NIC list includes substances and agents for which a limit or BEI is proposed for the first time, for which changes are proposed, for which retention as an NIC is proposed, or for which withdrawal of the adopted TLV or BEI is proposed. Substances and physical agents that appear on the NIC list are considered “trial values.” Chemical substances on the 2025 NIC list include carbon monoxide, 1,4-dioxane, ethyl acetate, and nitric acid. The physical agents on this year’s NIC list are static magnetic fields and whole-body vibration.

Chemical substances under study by ACGIH in 2025 include carbon nanotubes, diesel exhaust, fluorides, and lead. Physical agents on this year’s under study list are hand arm vibration, hand activity level, and lasers as they relate to optical radiation.

The full list of 2025 TLVs and BEIs is available on ACGIH’s website.