Module 8 of 8

What changed in December 2025

WHMIS is not frozen at 2015. Health Canada amended the Hazardous Products Regulations in December 2022 to bring Canada in line with the seventh revision of the GHS (and parts of the eighth). Suppliers had three years to switch over; the old rules stopped applying on December 15, 2025. If your last WHMIS course predates this, here is what is new.

1. A new hazard class: chemicals under pressure

Products that are liquids, pastes or powders packaged in a pressurized container with a propellant gas and dispensed as such, rather than as an aerosol spray. Think foam sealants, pressurized adhesives and some cleaning foams. They used to fall awkwardly between "aerosols" and "gases under pressure". Now they have their own class with two categories:

• Category 1 (flammable): flame and gas cylinder pictograms, signal word Danger.
• Category 2 (non-flammable): gas cylinder pictogram, signal word Warning.

Both carry the hazard statement about a pressurized container that may burst if heated.

2. Aerosols reorganized

The class formerly called "flammable aerosols" is now simply aerosols, with three categories. Categories 1 and 2 are flammable and keep the flame pictogram. The new category 3 covers non-flammable aerosols; it has no pictogram but still needs a label with the signal word Warning and the "pressurized container" statements. The practical effect: a non-flammable spray can is now formally a hazardous product that needs a supplier label and an SDS.

3. Flammable gases restructured

Flammable gases are now split into category 1A, which absorbs pyrophoric gases (ignite spontaneously in air) and chemically unstable gases as sub-categories, and category 1B for less flammable gases. The old standalone "pyrophoric gases" class is gone; its products live in 1A. Labels will show the additional hazard statements for pyrophoric or unstable gases where they apply.

4. A new class: desensitized explosives

Explosive substances that have been wetted or diluted with a phlegmatizer to suppress their explosive properties (certain nitrocellulose products, for example). They are classed in four categories with the flame pictogram and hazard statements warning that the fire or explosion risk returns if the desensitizing agent is lost. True explosives remain outside WHMIS under the Explosives Act.

5. Classification using non-animal data

Suppliers may now classify skin corrosion, skin irritation and eye damage using validated in-vitro (test-tube) methods and defined approaches rather than animal testing. You won't see this on a label, but it means some products have been reclassified as data was updated; a product you knew as an irritant may now be corrosive, or the reverse. Read the current label.

6. Updated statements and SDS detail

Precautionary statements were revised for clarity, and SDS requirements were tightened in places (for example, more detail on physical properties and particle characteristics in section 9). Suppliers were required to reissue labels and SDSs that no longer complied by the December 2025 deadline.

What it means for you on the floor

• Expect new labels and SDSs. Products bought after December 15, 2025 must comply with the amended rules. Stock already in your workplace may still carry older labels; your employer should obtain the updated SDS and tell you about any changed hazards.
• Pressurized cans are not "just cans". Non-flammable aerosols and chemicals under pressure now carry labels and SDSs. Store them away from heat; a container that may burst if heated is a hazard in a hot vehicle or near a space heater.
• The pictograms are the same. No new symbols were introduced; the changes are in classes, categories and statements behind them.
• The December 2025 deadline is a natural review point. Employers must review their WHMIS program annually anyway; the amendments are a reason to check the SDS library and the product inventory now.