Guides

WHMIS pictograms explained for Canadian workplaces

A WHMIS pictogram is a hazard warning on a product label, not a complete instruction for handling the product. Most are black symbols on white inside a red diamond. The biohazardous infectious materials symbol is the Canadian exception: it has a round black border. Read the pictogram together with the product identifier, signal word, hazard statements and precautions on the label, then check the matching safety data sheet (SDS) for the actual substance and task. Health Canada's current supplier guidance explains how symbols are assigned under the Hazardous Products Regulations (HPR).

WHMIS stands for the Workplace Hazardous Materials Information System. Canadian supplier classification and labels are regulated federally, while workplace education, training and use of hazard information are addressed by the relevant provincial, territorial or federal occupational health and safety law. This page is a symbol lookup. Complys' broader Canadian WHMIS guide covers the overall employer program, labels, SDSs and training. Keep those intents separate.

At-a-glance pictogram guide

Pictogram name and visual cue	Common hazards it can indicate	What a worker should check next
Flame — black flame in a red diamond	Flammability and certain reactive, self-heating or water-reactive hazards; some chemicals under pressure	Ignition sources, storage compatibility, temperature and emergency precautions on the SDS
Flame over circle — flame above a ring	Oxidizing hazard: can cause or intensify a fire	Separation from fuels/combustibles and approved storage or handling controls
Exploding bomb — bursting object	Severe self-reactivity or organic-peroxide hazards under WHMIS; do not assume every explosive product is classified under HPR	Heat, shock and incompatible-material controls; exact classification on label/SDS
Gas cylinder — horizontal cylinder	Gases under pressure and some chemicals under pressure	Pressure, temperature, cylinder securing, ventilation and release response
Skull and crossbones — skull above crossed bones	More severe acute toxicity: fatal or toxic in small exposure amounts	Exposure routes, containment, emergency first aid and PPE selected from SDS/risk review
Corrosion — liquid damaging a hand and surface	Skin corrosion, serious eye damage or corrosivity to metals	Splash prevention, compatible equipment, eyewash and first-aid instructions
Exclamation mark — `!`	Certain irritants, skin sensitizers, less severe acute toxicity and some specific target-organ effects	Which endpoint applies; avoid treating all `!` products as equivalent
Health hazard — person silhouette with chest starburst	Serious or longer-term health effects such as carcinogenicity, respiratory sensitization, reproductive toxicity or target-organ effects	Exposure assessment, substitution/engineering controls and any health-monitoring duties
Biohazardous infectious materials — biohazard sign in a black circle	Biohazardous infectious material under WHMIS	Containment, exposure prevention, disinfection and incident response
Environment — dead tree and fish	Aquatic environmental hazard under GHS	Not a required WHMIS pictogram; may appear as supplementary information. Check environmental and spill controls separately.

This table is a plain-language interpretation, not a classification tool. One product may display more than one pictogram; another hazardous product may have no prescribed pictogram for its category. Never choose a pictogram for a label solely from a product's trade name, smell or use. The supplier's classification, compliant label and SDS are the starting evidence. CCOHS's current WHMIS pictogram kit provides official-looking downloadable images and notes the environment symbol's optional status; Health Canada states the HPR's exact reproduction requirements for required supplier-label pictograms.

What each symbol means in practice

Flame: identify the specific fire or reaction hazard

The flame can appear for flammable gases, aerosols, liquids or solids and certain self-reactive, pyrophoric, self-heating or water-reactive products. It does not tell you that all of those products behave alike. A water-reactive substance calls for very different incident response from an ordinary flammable solvent. Read the actual hazard statements and SDS sections 2, 5, 7 and 10 for classification, firefighting, handling and stability information. Decide on ignition control, ventilation, segregation and emergency action for the specific product. Do not select a generic “flammable” storage cabinet without checking compatibility.

Flame over circle: oxidizer, not simply “flammable”

An oxidizer can cause or intensify combustion, including when stored near materials that ordinarily burn. The symbol is different from the flame because the hazard mechanism differs. A worker handling an oxidizing cleaner or chemical should check the SDS for incompatible materials, container specifications, spill response and the concentration actually used. Keeping a fuel away from ignition is not enough if an oxidizer is stored against combustible material.

Exploding bomb: severe reactivity, classification-specific

Under WHMIS this pictogram can indicate certain severe self-reactive substances and organic peroxides. Do not teach it as proof that the workplace product is an “explosive” in a separate legal classification; Canadian explosives have distinct regulatory treatment. Prevent heat, friction, shock or incompatible contact as specified by the product information, and use trained specialist procedures where indicated. The label and SDS identify the particular class and response; the symbol alone does not.

Gas cylinder: pressure hazards can be physical and chemical

The cylinder symbol warns that a container under pressure can rupture or release contents. A gas can also have flammable, toxic or oxidizing properties, so additional pictograms may appear. Secure cylinders and pressure vessels as required, protect valves, prevent heating, provide suitable ventilation and know what to do for a leak. Do not infer that a cylinder is harmless because the only obvious label symbol is a pressure pictogram.

Skull and crossbones: acute toxicity

This warns of potentially fatal or toxic effects after a relatively small or short exposure. The exposure route may be inhalation, skin contact or swallowing. Check the precise hazard statement and SDS first-aid/response instructions. Prevent exposure at source where feasible, plan containment and make emergency information accessible. A pair of gloves chosen by appearance is not an adequate control without checking chemical compatibility and the task.

Corrosion: skin, eyes or metal

The corrosion pictogram can describe skin corrosion, serious eye damage or corrosivity to metals. That does not mean each labelled product causes all three. Read the actual hazard statements. For a transfer operation, consider splash containment, compatible containers, eye/face protection, gloves selected for the product, accessible first aid and how contaminated clothing will be handled. Metal corrosion may also threaten piping or storage equipment even when direct skin exposure is controlled.

Exclamation mark: identify the endpoint

The exclamation mark can indicate skin or eye irritation, skin sensitization, less severe acute toxicity, respiratory irritation or drowsiness/dizziness from certain exposures. It is a mistake to translate it as merely “low risk.” A skin sensitizer can have lasting occupational consequences; a product causing dizziness can create an immediate task hazard. The hazard statement tells you which effect is present. Health Canada also has rules preventing redundant display of certain less severe symbols when a more severe hazard pictogram conveys the relevant effect; don't add icons by intuition.

Health hazard: serious or long-term effects

The silhouette with a starburst marks hazard classes such as carcinogenicity, respiratory sensitization, reproductive toxicity, germ-cell mutagenicity, target-organ toxicity or aspiration hazard. It can be more important to control routine repeated exposure than to wait for an immediate symptom. Check the route and category, then assess the actual task: opening containers, spraying, heating or grinding can change exposure. Use substitution, enclosure and ventilation where appropriate before relying only on PPE. An SDS is an input to the workplace assessment, not the assessment itself.

Biohazardous infectious materials: Canada's distinctive symbol

The black-circle biohazard pictogram is associated with biohazardous infectious materials under WHMIS. Its border differs from the red-diamond format of the other required pictograms. The specific organism/toxin, exposure route, containment, disinfection and medical response must come from the product information and the applicable biosafety and workplace rules. Avoid treating every biological waste container as if it were a supplier-labelled WHMIS product; identify the regulatory context.

Environment: familiar GHS image, different WHMIS status

Workers may see a dead tree and fish on an imported or supplementary label. Environmental hazard classification and labelling are not required under WHMIS, although the symbol may be used. Do not call the environment symbol the tenth mandatory Canadian WHMIS pictogram. Its presence may still matter for spill, waste and environmental controls under other laws. CCOHS makes the optional status explicit.

A pictogram is not the complete hazard decision

Suppose a technician receives a drum with a flame and health hazard pictogram. “It burns, so keep it away from sparks” addresses only one part of the problem. The SDS may show a solvent that can also cause organ effects after inhalation. The workplace must evaluate how the technician opens the drum, transfers liquid, cleans spills, disposes of waste and works near other people. Controls may include closed transfer, ventilation, ignition prevention and suitable emergency arrangements. Exact controls depend on the product and task; a red diamond does not calculate exposure.

In another example, a compressed gas container shows gas cylinder plus skull and crossbones. Securing it against falling addresses pressure but not a toxic release. The worker needs the label, SDS, leak procedure, ventilation and equipment suited to that gas. This is why a symbol-recognition quiz alone is not full workplace-specific WHMIS education.

How to read a supplier label and SDS together

Match the product identifier. Make sure the SDS corresponds to the container. Similar trade names or concentrations can have different hazards.
Read every pictogram and hazard statement. More than one hazard may apply. The signal word helps communicate severity but does not replace the detailed statement.
Read the precautions and relevant SDS sections. Section 2 identifies hazards; sections 4–8 cover first aid, firefighting, release, handling/storage and exposure controls; section 10 addresses stability and reactivity. Check the whole SDS for the product and task.
Assess how the product is actually used. Quantity, dilution, heat, aerosol generation, confinement and nearby workers change exposure. The label identifies inherent hazards; task conditions determine the workplace controls.
Keep information accessible and train workers. Follow the applicable employer WHMIS law in the province/territory or federal workplace. Use the broader WHMIS guide for program duties and the current regulator for local details.

Health Canada notes that some WHMIS classes or categories have no prescribed pictogram, including examples such as combustible dusts and simple asphyxiants. Lack of a red diamond is therefore not proof that a product is safe. Read the whole label and SDS and ask the supplier or competent safety adviser if the information is missing or inconsistent.

Frequent pictogram mistakes

Calling the environment pictogram mandatory WHMIS. It may be present, but environmental hazard classification was not adopted as a required WHMIS class.
Treating ! as harmless. The symbol may reflect sensitization, harmful acute toxicity or other effects; read the hazard statement.
Confusing flame with oxidizer. A flame over a circle warns that a product can intensify a fire; storage decisions differ.
Assuming one icon means one hazard. Products may have multiple pictograms and additional hazards in the statements/SDS.
Ignoring labels with no icon. Some hazard classes/categories have no prescribed pictogram.
Copying a symbol onto a workplace label without checking the product. Follow the applicable local workplace-label rule and the actual supplier label/SDS; do not invent a classification.
Using symbol recognition as the only training. Workers also need product-specific safe handling, storage, exposure controls and emergency actions.

How Complys relates to this task

The Canadian WHMIS and SDS software page is the relevant product destination for managing chemical information and training records only to the extent its current implementation is verified. The live marketing page claims an SDS library, labels/controls, expiry reminders and instant document retrieval, and displays a 30-day trial; other Canadian pages display a 90-day trial. This guide makes no claim that Complys classifies products, assigns legally correct pictograms, generates supplier labels, guarantees SDS currency or certifies WHMIS compliance. A supplier's current label/SDS and the applicable law remain the source of hazard information. Resolve the conflicting commercial terms and feature claims before a product CTA is promoted.

Questions about WHMIS pictograms

How many pictograms are there?

The answer depends on whether someone counts the optional environment symbol alongside the WHMIS-required pictograms and the Canadian biohazard symbol. A practical workplace chart often shows ten images, including environment. Do not turn that chart count into a claim that all ten must appear under WHMIS. The actual label displays the pictograms assigned to the product's classifications, subject to HPR rules.

Does every hazardous product have a pictogram?

No. Some classes/categories have no prescribed symbol. The label and SDS can still carry important hazard statements. Check the actual classification and product information.

Are WHMIS pictograms the same as old Canadian hazard symbols?

No. Modern WHMIS incorporates GHS-style red diamonds for most pictograms and the Canadian black-circle biohazard image. Old-style symbols on legacy material should not be used as the only source for a current hazard decision; check current labels and SDSs.

Can an employer create its own hazard pictogram?

Not as a substitute for a pictogram prescribed for a supplier label under the HPR. Health Canada specifies the required format and assignment. Workplace labels are governed by applicable employer law and may have different required elements; do not copy a supplier-label rule onto every secondary container without checking the local rule.

---

Writer-side source/claim register — researched 5 October 2026

Material claim	Primary/current source	QA decision
HPR pictogram assignment, format, biohazard exception and no-pictogram categories	Health Canada supplier guidance	Supplier-rule claims limited to federal HPR; employer workplace labels local-law gate.
Pictogram list and typical hazard classes	CCOHS WHMIS pictogram kit and CCOHS detailed fact sheet	Interpretations expressed as common meanings, not classification for a particular product.
Environment image not required under WHMIS	CCOHS pictogram kit	Explicitly separated from required pictograms.
SDS as source of product-specific hazard, precautions and response	CCOHS SDS fact sheet	Product and task assessment remains necessary.

Internal-link, owner and product QA

Proposed /ca/guides/whmis-pictograms-explained returned 404 on 5 October 2026. Final repository and unpublished-owner check required.
Existing Canadian WHMIS overview mentions pictograms in one short general section but does not provide a symbol-by-symbol lookup. This page owns the detailed interpretation and workplace decision task; the overview retains program/label/SDS/training ownership. No UK COSHH or US HazCom wording reused.
Pillar and money destination: Complys CA WHMIS & SDS software, observed live. Its trial and capabilities are whole-page verification gates; no unsupported feature or trial claim in article body.
Jurisdiction is Canadian WHMIS. Federal supplier rules and local employer rules are distinguished. Product pictograms are not used to infer task exposure. Copy, keyword and duplication checked writer-side. Add any official pictogram artwork only with correct shapes, source attribution/licensing and accessible text. READY remains writer-side; independent legal, implementation, route and whole-page QA required.