OSHA Hazard Communication Standard (HazCom, 29 CFR 1910.1200)

Who it applies to

HazCom applies to employers whose workers may be exposed to hazardous chemicals under normal conditions of use or in a foreseeable emergency, and to the manufacturers, importers and distributors who supply those chemicals. General industry, construction and shipyards are covered; the federal text for some sectors is in separate sections that incorporate the same standard. Many US states operate their own OSHA-approved state plans, which must be at least as effective as the federal rule.

There are exclusions where other laws apply: for example hazardous waste, tobacco products, wood products whose only hazard is flammability (treated wood, and wood that may be sawed or cut and generate dust, are not exempt), articles, food, drugs and cosmetics for personal consumption, and consumer products used for their intended purpose with no more exposure than a consumer would have. See SDS for consumer products.

What it requires

• Hazard classification by manufacturers and importers using GHS-based criteria for physical and health hazards. (Environmental hazards are not part of HazCom.)
• Labels on shipped containers with six elements: product identifier, signal word, hazard statements, pictograms, precautionary statements and supplier identification. See labeling requirements.
• Safety data sheets in the 16-section format, supplied by manufacturers and importers, passed on by distributors and maintained by employers. See the 16 sections.
• A written hazard communication program, including a chemical list, labeling, SDS access and training.
• Employee information and training, at initial assignment and when new hazards arise. See training requirements.

Appendix A and B set the health and physical hazard criteria; Appendix C covers label elements; Appendix D defines the SDS contents. Notes to paragraph (g)(2) say OSHA does not enforce the content of Sections 12 to 15, although their headings must appear.

The 2024 update

OSHA published a revised HazCom in May 2024, aligned primarily with Revision 7 of the UN GHS (the 2012 version followed Revision 3). The main changes:

• Updated classification criteria: a new hazard class for desensitized explosives, flammable gases split into Categories 1A and 1B (pyrophoric and chemically unstable gases now fall under 1A), and the aerosols class extended to non-flammable aerosols and chemicals under pressure.
• Label changes, including abbreviated labels for small containers (100 ml or less, with further relief at 3 ml or less) and rules for containers already released for shipment. See labeling requirements.
• Trade secret claims: a withheld concentration must be given as one of the prescribed ranges in paragraph (i). See trade secrets on SDSs.
• Updates to SDS content, such as the revised list of physical and chemical properties in Section 9.
• Technical clarifications and some changes in definitions.

The revised rule took effect on July 19, 2024. Under paragraph (j), as currently published by OSHA, manufacturers, importers and distributors had to comply for substances by May 19, 2026 and must comply for mixtures by November 19, 2027; employers must update workplace labeling, their hazard communication program and training by November 20, 2026 for substances and May 19, 2028 for mixtures. Until then either the 2024 or the previous version may be followed. Check OSHA's current text in case dates change. Also see SDS update requirements.

Key differences versus other systems

See also WHMIS, EU CLP and the UN GHS pages.

Practical compliance steps for employers

1. Build a chemical inventory.
2. Collect a current sheet for each item and make them accessible.
3. Check that containers are labeled, including secondary containers.
4. Write and implement the hazard communication program.
5. Train employees and keep records.
6. Review the program when you bring in new chemicals and when the rule changes.

Sheets and records have retention considerations under a separate standard; see how long to keep SDS records. Laboratories have a modified regime; see the OSHA laboratory standard.

Frequently asked questions