The OSHA Permissible Exposure Limit (PEL), Threshold Limit Value (TLV), and any other exposure limit recommended by the manufacturer, distributor, or employer preparing the SDS must be given if such values are available.

If such values are listed, they may indicate the maximum exposure a worker should have to the substance during an 8-hour working day, as expressed in parts per million (ppm) in air. The PEL is set by OSHA and is a mandated exposure level. However, some PELs have not been updated recently and a number of employers follow exposure limits based on TLVs.

The TLV is the recommended level set by the American Conference of Governmental Industrial Hygienists (ACGIH). TLVs are advisory guidelines that are revised each year as more information becomes available for different chemicals. TLVs are airborne concentrations of hazardous substances and their values vary from one substance to another.

This information can be found in Section II of the sample SDS form at the end of this unit.