US EPA Aligns with HazCom, Impacts Tier II Reporting, Omits Combustible Dust

The US EPA finalized a rule to conform the Federal environmental regulations with OSHA’s 2024 Hazard Communication Standard (HCS) update. In doing so, the Agency revised the EPCRA hazard categories and the definition of hazard category, removed an obsolete term, and acknowledged OSHA’s new definition for combustible dust without incorporating it into 40 CFR. The rule changes go into effect August 21, 2026.

View the Final Rule in the Federal Register.

The EPCRA Hazard Category Update

The EPA is adopting OSHA’s HCS definitions of “hazard category,” “health hazard,” and “physical hazard.” These new definitions will be used for reporting under the hazardous chemical inventory regulations.

Facilities must comply with these changes starting with the 2027 EPCRA §312 annual inventory reports (i.e., Tier II reporting), due March 1, 2028.

The pre-update definitions of these terms under EPCRA can be found at 40 CFR 370.66 before August 21, 2026.

Removing “MSDS” and Redefining “SDS”

“Material Safety Data Sheet (MSDS)” and “Safety Data Sheet (SDS)” have the same meaning in 40 CFR. Both terms have been used in tandem in the Federal environmental regulations since 2016. All uses of “Material Safety Data Sheet” and “MSDS” will be gone from 40 CFR 370 on August 21, 2026. The definition of “Safety Data Sheet” is changing to align with the definition in—you guessed it—the Hazard Communication Standard.

Find the definition of Safety Data Sheet that the Agency plans to incorporate here.

Why EPA Used Both “MSDS” and “SDS”

OSHA overhauled the HCS in 2012 to incorporate elements of the Globally Harmonized System, or GHS. One change was to replace “Material Safety Data Sheet,” or “MSDS,” with “Safety Data Sheet,” or “SDS,” throughout the Hazard Communication Standard.

The EPA followed OSHA’s lead and revised the EPCRA regulations in 2016 to align them with that 2012 OSHA Rule. The Agency knew that consistency with OSHA’s regulatory language was essential to limit confusion. At the same time, swapping out MSDS for SDS may have confused others.

So, the terms stayed in 40 CFR until the EPA determined that eliminating “Material Safety Data Sheet” would not cause confusion. In doing so, the EPA removed 200 words from the regulations while making those regulations easier to navigate and apply.

Omitting OSHA’s New “Combustible Dust” Definition

In 2024, OSHA codified this definition for combustible dust at 29 CFR 1910.1200(c): “Combustible dust means finely divided solid particulates of a substance or mixture that pose a flashfire hazard or explosion hazard when dispersed in air or other oxidizing media.’’

The EPA is not adding OSHA’s definition of combustible dust to its regulations.

The Agency acknowledged OSHA’s addition of this definition and stated that it is already applicable to 40 CFR 370 by way of the existing reference to the OSHA HCS within the definition of “hazardous chemical” at 40 CFR 370.66, which includes “any hazardous chemical as defined under 29 CFR 1910.1200(c),” with some exceptions.