Threshold Limit ValueTLV

Published annually by the American Conference of Governmental Industrial Hygienists (ACGIH). Three types: TLV-TWA (8-hr time-weighted average), TLV-STEL (15-min short-term exposure limit), and TLV-C (ceiling, never exceeded). TLVs are not regulatory limits (PELs are); however, they are often more current and health-protective than OSHA PELs.