Guidance on Reporting Mixtures

How can I tell whether a substance is a mixture?

According to 40 CFR 370.66, mixtures are defined under the Occupational Safety and Health Administration's Hazard Communication Standard in 29 CFR 1910.1200(c):

·  Mixture is a combination or a solution composed of two or more substances in which they do not react.

To assist with determining whether a substance is a mixture, check the Safety Data Sheet (SDS) for the composition information. If more than one component is listed, the substance is a mixture.

How do I report a mixture with hazardous chemicals that meet or exceed reporting thresholds?

Mixture containing EHS equal to or greater than reporting threshold

Determine the total quantity of the EHS present throughout your facility at any one time.

·  Report the EHS component in the mixture.

·  Report the mixture as a whole. If listed as a mixture, the EHS must be listed as a mixture component and marked as an EHS.

Mixture not containing EHS equal to or greater than reporting threshold

Hazardous mixtures over 10,000 lbs are reportable. Determine either the total quantity of the hazardous chemical component OR the total quantity of the mixture as a whole present throughout your facility at any one time.

·  Report the non-EHS component in the mixture.

·  Report the mixture as a whole.

How do I determine the quantity of a hazardous chemical or EHS component present in a mixture?

Multiply the percent of the hazardous chemical or EHS in the mixture by the weight of the whole mixture (in pounds).

In the example below, the mixture X-Chem weighs 20,000 lbs. and contains 20% of the hazardous chemical “Chemical A”, which is listed as an EHS, and 80% water:

1)  Hazardous component example:

  1. Weight of Chemical A= 20,000 x 20% = 4000 lbs.
  2. Weight of Water = 20,000 x 80% = 16,000 lbs.

Report 4,000 lbs of Chemical A in the Tier II Report.

2)  Whole Mixture Example:

  1. Weight of X-Chem = 20,000 lbs.

Report 20,000 lbs of the mixture in the Tier II Report.

  1. You would also list the 4,000 lbs of Chemical A under the Mixture Components because it is an EHS.

Mixture X-chem
Ingredient names / Product Identifer (CAS No.) / Percent (%)
Chemical A (EHS) / XXXX-XX-X / 20
Water / XXXX-XX-X / 80

You do not have to count a hazardous chemical present in a mixture if the concentration is less than or equal to 1%, or less than or equal to 0.1% for a carcinogenic, or potentially cancer-causing chemical.

How do I report Mixtures in the Tier2 Submit Software?