Frequent Questions

Sections 311 and 312 group chemicals according to hazard categories.  What are these categories?

In the law, the reporting requirements for Section 311 and Section 312 are based on the 23 physical and health hazards identified under OSHA regulations.  Under Sections 311 and 312, EPA was permitted to modify these categories of health and physical hazards.  EPA recognized that a smaller number or reporting categories might make managing the information easier as well as increase its usefulness, particularly since information on chemicals that present more than one hazard must be provided in all applicable categories.  Based on public comment, EPA modified OSHA's 23 hazard categories to the following five hazard categories:

• Immediate (acute) health hazard, includes "highly toxic," "toxic," "irritant," "sensitizer," "corrosive," and other hazardous chemicals that cause an adverse effect to a target organ which usually occurs rapidly as a result of a short term exposure.

• Delayed (chronic) health hazard, includes "carcinogens" and other hazardous chemicals that cause an adverse effect to a target organ and the effect of which occurs as a result of long term exposure and is of long duration.

• Fire hazard, includes "flammable," "combustible liquid," "pyrophoric," and "oxidizer."

• Sudden release of pressure hazard, includes "explosive," and "compressed gas."

• Reactive hazard, includes "unstable reactive," "organic peroxide," and "water reactive."

Have more questions? Submit a request