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Safety data sheets and chemical product labels are important tools for ensuring the safe transport, storage, handling, and use of hazardous substances. In the U.S., chemical product manufacturers, distributors, and importers have been required to provide SDSs since 2012, when OSHA updated its hazard communication standard (29 Code of Federal Regulations 1910.1200) to align with Revision 3 of the Globally Harmonized System of Classification and Labelling of Chemicals (GHS). Even occupational and environmental health and safety professionals who aren’t SDS or product label authors may find these documents useful when selecting personal protective equipment, first aid protocols, and hazard controls.  

Attaining a solid understanding of SDSs and product labelling requirements is complicated by the near-constant stream of regulatory changes. Since the first revision was published in 2005, the GHS has been updated every two years. Revision 11 was published in 2025, and Revision 12 is expected in 2027. Countries that have adopted the GHS must periodically refresh their national hazard communication standards to implement the changes. In recent years, OSHA has revised its HCS, Canada has made changes to its Workplace Hazardous Materials Information System (WHMIS), and the EU has updated two of its main chemical regulations.  

Fortunately, SDS authors don’t need to reclassify all the chemicals in their organization’s inventory with every new GHS revision. Most changes are clarifications and improvements to classification language that don’t affect core criteria. Occasionally, however, GHS revisions produce significant changes in national regulations. Hazard communication professionals must anticipate developments that may affect their organizations’ products.

Updates to OSHA HCS

In 2024, OSHA finalized changes to the HCS that aligned the standard with GHS Revision 7, as well as aspects of Revision 8. All versions of GHS may be downloaded for free from the website of the United Nations Economic Commission for Europe.

One of the more important changes introduced in GHS Revision 7 addressed the classification of flammable gases. Although previous versions had only distinguished between Category 1 and 2 flammable gases, this revision divided Category 1 into 1A and 1B and further subdivided Category 1A into pyrophoric and chemically unstable gases. The main aspects of GHS Revision 8 integrated into the 2024 HCS include the chemicals under pressure classification, as well as provisions for in vitro, ex vivo, and non-animal testing methods. Aerosols are no longer classified as chemicals under pressure but may fit criteria for other hazard classes. These changes may require major revisions to SDSs and product labels.

Other changes introduced by the 2024 HCS include clarification of OSHA’s definition of bulk shipment: “any hazardous chemical transported where the mode of transportation comprises the immediate container.” This contrasts with the definition set by the U.S. Department of Transportation, which focuses on the capacity of the container used to transport a given material. New labelling requirements for small containers have been adapted from WHMIS. OSHA’s provisions for trade secrets now include lists of prescribed concentration ranges, also inspired by Canadian standards. These changes may require SDS authors to make significant changes to Section 9, which covers chemical and physical properties.

The new HCS became effective for suppliers on July 19, 2024. For chemical manufacturers, importers, distributors, and employers evaluating substances, compliance with the updated standard was required by Jan. 19, 2026. For those evaluating mixtures, the compliance date is July 19, 2027. Employers must update workplace labeling and hazard communication programs, as well as provide training to workers by July 20, 2026, for substances and by Jan. 19, 2028, for mixtures.

Developments in Global Hazard Communication

U.S. and Canadian hazard communication standards are intertwined, as shown by the adoption of certain Canadian practices by the 2024 HCS. And since Canada is one of the United States’ most important trading partners, hazard communication professionals based in the U.S. may benefit from understanding Canadian requirements.

The Canadian hazard communication standard, WHMIS, is also aligned with GHS Revision 7. In December 2022, Canada finalized revisions to the standard that may require SDS authors to make significant changes to Sections 3, 9, and 14.

U.S.-based SDS authors should also be aware of regulatory developments in Europe, as the EU is a major influence on GHS revisions. For example, the European Chemicals Agency (ECHA) introduced several new hazard classes in 2023: endocrine disruptors for human health and the environment; persistent bioaccumulative and toxic chemicals; and persistent, mobile, and toxic chemicals. The EU is now advocating for these categories to be added to the GHS.  

In EU member states, chemical product labels are governed by the Classification, Labelling, and Packaging (CLP) Regulation, a new version of which came into force in 2024. But SDSs are covered by REACH, which stands for Registration, Evaluation, Authorization, and Restriction of Chemicals. The United Kingdom inherited the CLP and REACH frameworks, but its national regulations have begun to diverge since it left the EU in 2020.

In 2024, the EU finalized changes to CLP that improved the clarity and accessibility of information on product labels. For example, restrictions on fold-out labels were loosened to accommodate information in multiple languages and digital labels providing supplementary information were permitted. The European Commission has provided a summary of the changes.  

Besides the new hazard categories added in 2023, the EU significantly revised the requirements for SDSs in 2020. These changes address information about poison centers and unique formula identifiers, concentration limits and multiplying factors, listing of unclassified substances, end uses and exposure scenarios, and justifications for not including certain hazard classifications, as well as endocrine disrupting properties.

In September 2025, ECHA CHEM became available. This database provides information drawn from documentation submitted by suppliers and exporters for all chemicals registered in the EU. Hazard communication professionals in all countries may find ECHA CHEM a reliable, publicly available source of chemical classification information.

Learn More

AIHA has also updated its SDS and Label Authoring Course to cover the changes to GHS, HCS, WHMIS, and the EU’s hazard communication standards. Although primarily intended to help individuals preparing for the SDS and Label Authoring Registry exam, any hazard communication professionals seeking a more thorough understanding of SDSs will benefit from this online course. The new material comprises two and a half hours of additional instruction that covers GHS Revisions 4 through 11, OSHA HCS 2024, and changes to Canadian and European chemical regulations.

The instructors of the SDS and Label Authoring Course are Denese Deeds, CIH, FAIHA, SDSRP; Chandra Gioiello, CIH, SDSRP; Catherine Jacobson, PhD, DABT; Bob Skoglund, PhD, DABT, CIH; and Robert Roy, PhD, DABT. Participants earn 18.5 contact hours toward CIH recertification. To register for the course, visit AIHA’s website.