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Crosswalk Aligning EPA's Hazard Categories with OSHA's Hazard Classification

Pursuant to 40 CFR 370.42(s)(5), an owner or operator submitting EPCRA Tier II inventory information must indicate the hazard categories that apply to the chemical or mixture. The five hazard categories are defined in 40 CFR 370.66. How do the EPA hazard categories correspond to the Occupational Safety and Health Administration (OSHA) hazard classification system?

EPA developed a crosswalk with OSHA to align EPA’s hazard categories with the Globally Harmonized System (GHS) for Hazard Communication adopted by OSHA in 2012 (effective in 2015). The crosswalk is available at the following URL: