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Definition of hazardous chemical and OSHA's MSDS requirement for determining applicability of EPCRA 311/312

The requirements of 40 CFR Part 370, promulgated pursuant to EPCRA Sections 311 and 312, apply to facilities that have certain quantities of hazardous chemicals for which they are required, under the Occupational Safety and Health Act (OSHA), to prepare or have available Material Safety Data Sheets (MSDSs). How should a facility determine whether it must comply with 40 CFR Part 370 if it is uncertain whether it has a hazardous chemical for which OSHA requires an MSDS?

There is no comprehensive list of hazardous chemicals. The EPCRA regulations in 40 CFR Part 370 cite OSHA's broad definition of hazardous chemical (with certain exceptions listed in EPCRA Section 311(e)), which includes any element, compound, or mixture of elements that is a physical hazard or a health hazard (29 CFR Section 1910.1200(c) and 40 CFR Section 370.2). Health hazards include, among others, chemicals that are carcinogens, toxics, reproductive toxins, irritants, corrosive, neurotoxins, hepatotoxins, and chemicals that damage the lungs, skin, eyes, or mucous membranes (29 CFR Section 1910.1200(c) and Appendix A). Physical hazards include, among others, chemicals that are combustible, explosive, flammable, oxidizers, reactive, unstable, water-reactive, as well as compressed gases (29 CFR Section 1910.1200(c)).

OSHA's Hazard Communication Standard (29 CFR Section 1910.1200) requires chemical manufacturers and importers to obtain or develop an MSDS for each hazardous chemical that they produce or import, and requires employers to have an MSDS available for each hazardous chemical that they use (29 CFR Section 1910.1200(g)). OSHA regulations list several exemptions to the Hazard Communication Standard in 29 CFR Section 1910.1200(b)(6).

OSHA provides the following guidance regarding which chemicals are covered by the Hazard Communication Standard:

The Hazard Communication Standard applies to any chemical with an OSHA permissible exposure level, anything listed with a threshold limit value by the American Conference of Governmental Industrial Hygienists, any carcinogen listed by the International Agency for Research on Cancer (Groups 1, 2A, and 2B), any carcinogen listed by the National Toxicology Program, or any chemical regulated by OSHA as a carcinogen. In addition to these chemicals, the Hazard Communication Standard applies to any substance for which there is statistically significant evidence, based on at least one positive study conducted in accordance with established scientific principles, that indicates a health hazard as defined in 29 CFR Section 1910.1200(c).

One option for facility owners or operators who are not certain whether they have a hazardous chemical that requires an MSDS under OSHA is to contact the manufacturer of the substance for assistance in making this determination. The manufacturer (or importer) of a particular chemical substance has the primary responsibility under OSHA for determining whether that chemical is subject to OSHA's MSDS requirements. OSHA regulations require manufacturers and importers to provide information on the hazard of their chemicals to persons using or distributing those chemicals.

A second option for such owners or operators is to assume that an MSDS is required, and to determine whether the requirements in 40 CFR Part 370 apply, based on whether or not the substance was present at the facility in a threshold amount or more.

Facility owners or operators who require additional assistance in determining whether or not they are subject to OSHA's Hazard Communication Standard (i.e., the MSDS requirements) may contact the appropriate local area OSHA office. Check the blue pages of a local telephone directory, under United States Government, Department of Labor, for telephone and address information.