Overview of the 2024 HazCom Rule Changes
On May 20, 2024, OSHA published a final rule updating the Hazard Communication Standard (29 CFR 1910.1200) to align with the seventh revision of the Globally Harmonized System of Classification and Labelling of Chemicals (GHS Rev 7). This is the most significant update to HazCom since 2012, when OSHA first adopted GHS.
The rule impacts every employer in the United States who uses, stores, or handles hazardous chemicals—from construction sites to manufacturing plants, laboratories to warehouses. Understanding these changes is critical for maintaining compliance and avoiding costly citations.
Why OSHA Updated the Standard
OSHA's primary motivations for this update include:
GHS Revision 7: What Changed
New Hazard Categories for Flammable Gases
GHS Rev 7 introduces two new subcategories for flammable gases:
| Category | Criteria | Examples |
|----------|----------|---------|
| 1A — Pyrophoric Gas | Ignites spontaneously in air at or below 130°F | Silane, phosphine |
| 1B — Chemically Unstable Gas | May react violently without air exposure | Certain industrial process gases |
What this means for you: If you use welding gases, cutting gases, or specialty gases on construction sites, check with your supplier for updated SDSs reflecting these new subcategories. Labels must now distinguish between 1A and 1B flammable gases.
Aerosols Reclassified
The old "flammable aerosol" category has been replaced with a broader "Aerosols" classification that includes three cate