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Emergency Planning and Community Right-to-Know Act (EPCRA)
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How are mixtures handled for Sections 311 and 312 reporting?

The owner or operator of a facility may meet the requirements of Sections 311 and 312 by choosing one of two options:

• Providing the required information on each component that is a hazardous chemical within the mixture.  In this case, the concentration of the hazardous chemical in weight percent must be multiplied by the mass (in pounds) of the mixture to determine the quantity of the hazardous chemical in the mixture.  No MSDS has to be submitted for hazardous components in a mixture with quantities in concentrations under 0.1 percent for carcinogens and 1 percent for all other hazardous components of the total weight of the mixture.

• Providing the required information on the mixture as a whole, using the total quantity of the mixture.

When the composition of a mixture is unknown, facilities should report on the mixture as a whole, using the total quantity of the mixture.  Whichever option the owner or operator decides to use, the reporting of mixtures must be consistent for Sections 311 and 312, where practicable.

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Last updated on May 30, 2023
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