What is a Threshold Limit Value (TLV)?
Threshold Limit Values (TLVs) are the most common type of OEL. The American Conference of Governmental Industrial Hygienists (ACGIH) sets the TLVs to help evaluate workplace health hazards. TLVs are designed as guidelines to be used by people trained in industrial hygiene. There are TLVs for many workplace hazards including chemicals, vibration, heat, and ultraviolet light. Over 675 TLVs are for chemicals alone. The ACGIH prints a TLV booklet each year that includes the new and changed TLVs. The booklet contains other useful information. For example, the skin notation says if the chemical causes harm by getting into the body through the skin. The booklet also says whether some chemicals cause cancer. In another book, the TLV Documentation, the ACGIH gives the reason why a specific amount was selected for the TLV. (See #1 and 2 on the Resource List.
