No products in the cart.
WHMIS vs GHS: What's the Difference and How Do They Connect?
One is Canada's law, the other is the world's rulebook. Here is exactly how they fit together, what Canada kept for itself, and the 2025 deadline most workplaces have not heard of.
Quick answer
WHMIS and GHS are not the same thing, and neither replaced the other. GHS is the Globally Harmonized System, the United Nations rulebook for classifying and labelling chemicals worldwide. WHMIS is Canada's own workplace hazard law, which incorporated the GHS on February 11, 2015, through the Hazardous Products Regulations. Canada adopted the GHS physical and health hazard classes, skipped the environmental classes, and kept one hazard class the rest of the world does not have.
What GHS actually is
Every training session I have run hits this question within the first ten minutes: "Wait, is it WHMIS or GHS? Did GHS replace WHMIS? Which certificate do I need?" The confusion is understandable, because both names appear on the same labels. So let's start with what the official guidance says GHS is.
Health Canada's supplier guidance describes it this way: "The GHS covers all hazardous substances and mixtures and applies to all potential exposures to all hazardous chemicals in all types of situations, including production, storage, transport, workplace use, consumer use and in the environment. The GHS (commonly referred to as 'The Purple Book') standardizes the criteria for classifying chemicals according to their health, environmental and physical hazards, and standardizes the hazard communication requirements for labelling and SDSs."
In plain terms: GHS is the United Nations rulebook. It is not a law anywhere on its own. Each country decides how to write it into their own legislation, and that is where WHMIS comes in. So how exactly did Canada bolt a global rulebook onto a safety system it had been running since 1988? There is a precise date, and it is the answer to half the quiz questions at the end of this article.
How Canada built GHS into WHMIS
Canada did not throw WHMIS out. It renovated it. The mechanism was federal legislation, and the guidance spells out the exact sequence:
"On February 11, 2015, the Government of Canada published the HPR, which, in addition to the amendments made to the HPA, modified WHMIS to incorporate the GHS. The Controlled Products Regulations, the predecessor to the HPR, and the Ingredient Disclosure List were repealed."
Guidance on the WHMIS supplier requirementsHealth Canada (canada.ca)
The legal groundwork came a few months earlier: the Hazardous Products Act was amended by the Economic Action Plan 2014 Act, No. 1 to incorporate the GHS, receiving Royal Assent on June 19, 2014 and coming into force on February 11, 2015. That renovated system is what everyone calls WHMIS 2015.
The payoff, per the guidance, is that WHMIS classification and communication requirements became aligned with the United States and Canada's other trading partners. One label language for a continent of chemistry. But "aligned" is not "identical," and the differences Canada deliberately kept are the part almost nobody teaches. One of them is printed inside a round black border, and it exists in no other country's system.
What Canada skipped, and what Canada kept
GHS offers three groups of hazards. Canada took an editor's pen to all three:
- Physical hazards: adopted, minus explosives. All GHS physical hazard classes from the seventh revised edition were adopted, except Explosives and Desensitized Explosives, because explosives are excluded from the Hazardous Products Act entirely and regulated under the Explosives Act instead.
- Health hazards: adopted, plus two Canadian additions. All GHS health hazard classes came in. Canada also retained Biohazardous Infectious Materials, which is not a GHS class, and introduced Health Hazards Not Otherwise Classified, both to keep worker protection at least as strong as before.
- Environmental hazards: not adopted. The guidance is blunt about why: WHMIS covers workplace hazards, and "environmental hazards are not considered to be workplace hazards."
Then there is the pictogram every Canadian worker should recognize at a glance: "The Biohazardous Infectious Materials pictogram consists of a black biohazard symbol against a white background within a round black border." Round and black, while every GHS pictogram sits in a red diamond. If you ever see that circle, you are looking at the one hazard class that is uniquely ours.
Canada also kept requirements the GHS does not impose: bilingual labels and SDSs, a Canadian supplier identifier on both, and the duty to update labels and SDSs when significant new data appears. This is why, as CCOHS warns, a GHS-compliant SDS from another country may still not comply with Canadian law. Keep that in mind next time a US supplier tells you their paperwork "is already GHS." So what did all of this actually change on the shop floor when the switch flipped? Six things, and one of them quietly deleted a rule your senior coworkers still believe exists.
WHMIS 1988 vs WHMIS 2015: what changed
The federal WHMIS legislation summary lists the key changes, and they touch every label and binder in the building:
| Element | WHMIS 1988 | WHMIS 2015 (GHS-aligned) |
|---|---|---|
| Product term | Controlled Products | Hazardous Products |
| Hazard classes | Fewer classes and categories | Different and more numerous classes and categories, with criteria that better indicate hazard severity |
| Labels | Old symbols | New pictograms plus prescribed hazard statements and signal words |
| Data sheets | MSDS | SDS with a standardized 16-section format and prescribed information elements |
| Updates | MSDS updated every 3 years | SDS updated on an ongoing basis as new information appears; the 3-year rule is gone |
| Training language | Blended | "Education" (general: labels, SDS format, significance) vs "Training" (workplace- and job-specific), and both are required |
That last row matters more than it looks: per Nova Scotia's safety notice, education is the portable knowledge about how labels and SDSs work anywhere, and training is what your specific workplace does with its specific products. An online WHMIS course delivers the education layer; your employer owes you the site-specific layer on top. Now for the part of this story most articles stop before reaching: WHMIS did not stop changing in 2015, and there is a compliance deadline sitting in December 2025 that many suppliers scrambled to meet. Here is the whole timeline.
The full timeline, 2014 to 2025
| Date | What happened |
|---|---|
| June 19, 2014 | HPA amendments incorporating the GHS receive Royal Assent (Economic Action Plan 2014 Act, No. 1) |
| February 11, 2015 | Hazardous Products Regulations published; WHMIS incorporates the GHS; Controlled Products Regulations repealed. WHMIS 2015 begins |
| June 1, 2018 | Deadline for suppliers to convert WHMIS 1988 labels and MSDSs to WHMIS 2015 labels and SDSs |
| December 1, 2018 | Employers must be fully compliant with WHMIS 2015 labelling and SDS requirements (employer transition period ended November 30, 2018) |
| December 15, 2022 | Updates to the HPA and regulations come into force. The updated system is "amended WHMIS"; WHMIS 2015 becomes "former WHMIS" |
| January 4, 2023 | HPR amendments published moving Canada from the 5th to the 7th revised edition of the GHS, plus the new Chemicals Under Pressure class from the 8th edition |
| December 15, 2025 | End of the 3-year supplier transition period to bring classifications, SDSs, and labels into compliance with amended WHMIS |
The 2023 technical changes are deep in the weeds. Still, a few affect real products on real shelves: Flammable Aerosols became simply Aerosols with a new non-flammable category; aerosols no longer need a second classification as Gases Under Pressure; Pyrophoric Gases was repealed and folded into Flammable Gases Category 1A; and a brand-new Chemicals Under Pressure class arrived from the 8th edition of the GHS. If your safety binder still says "Flammable Aerosols," it is describing former WHMIS.
Which raises the question that actually brought most readers to this page: with all these versions flying around, what training do you personally need, and does the certificate work outside Canada? Straight answers below.
One course. Current system. About an hour.
Canadian Standards-Compliant WHMIS training built on the current GHS-aligned system, for $12.95. Register in 30 seconds and print your certificate the same day.
Register Now4.8 / 5 from 1,711 verified reviews · Over 200,000 Canadians trained
Training a whole team on the current system? Group and bulk registration handles everyone at once. And for the deeper 1988-to-2015 story, see our full breakdown of WHMIS 2015 vs WHMIS 1988.
Frequently asked questions
Is WHMIS the same as GHS?
No, but they are closely linked. GHS is the international system for classifying and labelling chemicals; WHMIS is Canada's national workplace law, which was aligned with the GHS in 2015. Even a GHS-compliant SDS from abroad may not comply with Canada's federal WHMIS legislation.
Did GHS replace WHMIS?
No. On February 11, 2015, the Hazardous Products Regulations modified WHMIS to incorporate the GHS. WHMIS remains the Canadian system, updated again in December 2022 as "amended WHMIS," now built on the 7th revised edition of the GHS with one class from the 8th.
Is WHMIS certification valid internationally?
WHMIS is Canadian legislation, and each country writes the GHS into its own laws with its own requirements. The knowledge transfers well since pictograms and SDS formats are harmonized. Still, other countries have their own training rules, so confirm the local requirement before relying on a Canadian certificate abroad.
Do US OSHA HazCom documents count in Canada?
Not automatically. Health Canada's guidance states that an SDS and label compliant with the US HCS may not be sufficient for compliance in Canada, because of Canadian requirements like bilingual labels and SDSs, a Canadian supplier identifier, and the Biohazardous Infectious Materials class.
What pictogram is unique to Canada?
Biohazardous Infectious Materials: a black biohazard symbol on a white background inside a round black border. It is not a GHS class; Canada retained it to maintain worker protection, which is why it breaks the red diamond pattern of every other pictogram.
Test your knowledge: the 10-question WHMIS vs GHS quiz
Dates, diamonds, and one round black border. Tap each question to reveal the answer.
1. GHS is commonly referred to by which nickname?
The Purple Book, per Health Canada's supplier guidance.
2. Which GHS hazard group was NOT adopted into Canada's WHMIS system?
Environmental hazards. WHMIS covers workplace hazards, and environmental hazards are not considered workplace hazards.
3. What shape frames a standard GHS hazard pictogram in Canada?
A red diamond, a square set on one point. The lone exception is the round black border of Biohazardous Infectious Materials.
4. Under WHMIS 2015, what were "Controlled Products" renamed to?
Hazardous Products, one of the key changes in the federal legislation.
5. How often must suppliers update an SDS when no new hazard data exists?
There is no fixed schedule anymore. The old 3-year update rule is gone; SDSs are updated on an ongoing basis as new information about a product becomes available.
6. When does the "amended WHMIS" supplier transition period end?
December 15, 2025, three years after the December 15, 2022 amendments came into force.
7. Which physical hazard class was repealed and merged into Flammable Gases?
Pyrophoric Gases, now included in Category 1A of the revised Flammable Gases class.
8. WHMIS "education" refers to what kind of information?
General, portable information: how labels and safety data sheets work and what their contents mean. "Training" is the workplace- and job-specific layer, and both are required.
9. True or false: Canada adopted the GHS Explosives hazard classes into the HPR.
False. Explosives are excluded from the Hazardous Products Act and regulated under the Explosives Act instead.
10. What was the Manitoba deadline for employers to fully comply with WHMIS 2015?
December 1, 2018, following the employer transition period that ended November 30, 2018.
Sources: Health Canada, WHMIS supplier requirements guidance (canada.ca) and provincial WHMIS regulations. New to the system? Start with our Complete Guide to WHMIS in Canada or learn every symbol in WHMIS pictograms explained.