Threshold Limit Values (TLVs) are guidelines established to protect workers from the adverse effects of exposure to hazardous substances in the workplace. These values represent the level to which it is believed that a worker can be exposed day after day for a working lifetime without adverse health effects. TLVs are developed by the American Conference of Governmental Industrial Hygienists (ACGIH), and they play a critical role in occupational health and safety standards.
