- October 15, 2025
- Kevin Kholer
WHMIS Has Been Amended: What Changed and How to Comply (2025 Update)
Canada has amended the Hazardous Products Regulations (HPR) under WHMIS to align with the UN Globally Harmonized System (GHS) Revision 7 and selected elements of Revision 8. The amendments came into force December 15, 2022, with a three-year transition that ends December 14, 2025. After that date, suppliers and workplaces must be fully compliant with the amended HPR.
The Big Picture (What’s New)
New/changed hazard classes and categories
- Chemicals Under Pressure: brand-new physical hazard class.
- Aerosols: class renamed from “Flammable Aerosols” to “Aerosols” and adds Category 3 (non-flammable aerosols).
- Flammable Gases: Category 1 is now split into 1A and 1B, and pyrophoric gases/chemically unstable gases are addressed within 1A; the separate “Pyrophoric Gases” class is repealed.
Safety Data Sheet (SDS) content updates
- Section 9 (Physical & Chemical Properties) is revised (e.g., particle characteristics added; evaporation rate removed; terminology updates like relative vapour density and kinematic viscosity).
- Mixture ingredient disclosure tightened: all hazardous ingredients above cut-off levels must be disclosed, even if they don’t drive classification.
- Combustible dust may now use an alternate hazard statement: “May form explosible dust-air mixture.”
Administrative and clarity improvements
- Allows narrower concentration ranges (still within prescribed bands) for trade-secret concentrations on SDSs.
- Clarifies significant new data obligations: when you issue updated SDSs/labels, include the changes and the date the new data became available.
Who Must Comply?
- Suppliers/manufacturers/importers/distributors of hazardous products: classification, labels, and SDSs must follow the amended HPR by the end of transition. During the transition you may comply entirely with either the former or amended HPR—but not a mix. Be ready to show which version you’ve used.
- Employers: provincial/territorial OHS laws continue to require a compliant WHMIS program (training, labels, current SDS access, and controls). Inspectors may verify training, labels, and SDS currency.
Key Dates
- December 15, 2022 – Amendments in force.
- December 14, 2025 – Transition ends; all parties must comply with the amended HPR. (CCOHS and Health Canada both confirm this date.)
What Companies Need to Do (Practical Checklist)
For Employers (Most Workplaces)
- Inventory & Gap Check
- Compile your chemical inventory; identify products with Aerosols, Flammable Gases, or potential Chemicals Under Pressure. Flag any SDS issued before the amendments or missing revised Section 9 data.
- Compile your chemical inventory; identify products with Aerosols, Flammable Gases, or potential Chemicals Under Pressure. Flag any SDS issued before the amendments or missing revised Section 9 data.
- Update SDS Library
- Request updated SDSs from suppliers (especially where hazard classes changed or Section 9 elements are out-of-date). Ensure SDSs disclose all hazardous ingredients above cut-offs.
- Request updated SDSs from suppliers (especially where hazard classes changed or Section 9 elements are out-of-date). Ensure SDSs disclose all hazardous ingredients above cut-offs.
- Verify Labels
- Confirm supplier labels reflect the new classes/categories (e.g., Aerosols (Category 3)) and that any combustible dust statements use approved wording.
- Confirm supplier labels reflect the new classes/categories (e.g., Aerosols (Category 3)) and that any combustible dust statements use approved wording.
- Refresh WHMIS Training
- Update education/training to cover:
- New Chemicals Under Pressure class
- Revised Aerosols and Flammable Gases structure
- What changed on SDSs (new/renamed properties)
- New Chemicals Under Pressure class
- Keep records; inspectors may confirm training occurred and workers understand hazards, protection, emergencies, and where to find SDSs.
- Update education/training to cover:
- Revise Procedures
- Update internal procedures for SDS currency (e.g., swaps on receipt), label checks, and handling significant new data (triggering SDS/label updates with dates).
- Update internal procedures for SDS currency (e.g., swaps on receipt), label checks, and handling significant new data (triggering SDS/label updates with dates).
- Coordinate Across Jurisdictions
- If you operate in multiple provinces/territories or under the federal Labour Program, confirm any jurisdiction-specific implementation guidance while aligning to the federal HPR.
- If you operate in multiple provinces/territories or under the federal Labour Program, confirm any jurisdiction-specific implementation guidance while aligning to the federal HPR.
For Suppliers/Manufacturers/Importers
- Re-classify Products
- Apply amended criteria—especially for Flammable Gases (1A/1B), Aerosols (incl. Category 3), and Chemicals Under Pressure.
- Apply amended criteria—especially for Flammable Gases (1A/1B), Aerosols (incl. Category 3), and Chemicals Under Pressure.
- Re-label
- Update signal words, hazard and precautionary statements, and category designations consistent with the amended HPR.
- Update signal words, hazard and precautionary statements, and category designations consistent with the amended HPR.
- Re-author SDSs
- Implement Section 9 changes (particle characteristics, terminology updates) and ensure ingredient disclosure rules are met; use narrower concentration ranges where appropriate.
- Implement Section 9 changes (particle characteristics, terminology updates) and ensure ingredient disclosure rules are met; use narrower concentration ranges where appropriate.
- Document Significant New Data
- When new data affects classification/SDS/labels, issue updated documents including the changes and the availability date of the new data.
- When new data affects classification/SDS/labels, issue updated documents including the changes and the availability date of the new data.
During the Transition (Now → December 14, 2025)
You may choose to comply entirely with the former HPR or the amended HPR—but not a combination. Your SDS and label for any given product must be fully aligned to the version you chose, and you should be able to demonstrate which version on request. Plan to complete all updates well before the deadline to avoid supply interruptions.
How InUnison Can Help
- SDS Management: centralize current SDSs and set reminders to replace outdated versions.
- Training: deliver a short refresher module on the new hazard classes and SDS Section 9 changes.
Label & Program Audit: verify labels and written WHMIS program align with the amended HPR and jurisdictional expectations (records, worker competency evidence).
Frequently Asked Questions
No. CCOHS refers to “former WHMIS” (WHMIS 2015) and “amended WHMIS” after the 2022 amendments.
A new hazard class (Chemicals Under Pressure) was adopted with associated label elements; check supplier labels and SDSs for the correct statements and symbols.
After December 14, 2025, suppliers and workplaces are expected to be fully compliant with the amended HPR; jurisdictions enforce WHMIS under OHS laws, and inspectors can verify training, labels, and SDS currency.
Sources & Further Reading
- Health Canada – Amendments to the Hazardous Products Regulations (HPR): coming-into-force, transition rules, and detailed table of changes. (Government of Canada)
- CCOHS – WHMIS Legislation: overview of employer duties and confirmation of the December 14–15, 2025 transition end. (CCOHS)
- Canada Gazette, Part II (Jan 4, 2023) – official text of the HPR amendments (GHS Rev. 7, selected Rev. 8). (www.gazette.gc.ca)
- Chemscape summary – practical breakdown of what changes on SDSs and key hazard-class updates. (chemscape.com)