WHMIS study guide: key rules on all 14 topics

Free WHMIS study guide: 293 key points from the CCOHS OSH Answers: WHMIS fact sheets in plain words, organised by topic, each topic linked to its practice questions.

By the Canada Exam Prep Editorial Team · Updated October 15, 2026

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This study guide collects our notes on every topic of the WHMIS Training Quiz (WHMIS 2015 / GHS) on one page: 293 short points in our own words, grouped by topic and by handbook section. Read it from top to bottom before your first practice test, or jump to a topic from the list below.

Each topic ends with a link to its practice questions, so you can check what you just read straight away, and a link to the official chapter for the full wording. The notes summarise the CCOHS OSH Answers: WHMIS fact sheets from the Health Canada (supplier rules) and provincial, territorial and federal OHS regulators (workplace rules); they do not replace it, and where our notes and the official source differ, the official source wins.

Study these notes as flashcards →

What WHMIS is

What the Workplace Hazardous Materials Information System is, its four main parts, how it lines up with the GHS, what counts as a hazardous product and which products are excluded.

Practise What WHMIS is questions Flashcards Official chapter

What is WHMIS?

WHMIS = Workplace Hazardous Materials Information System.
It is a Canada-wide system that gives health and safety information about hazardous products meant to be used, handled or stored in Canadian workplaces.
WHMIS is aligned with the GHS (Globally Harmonized System of Classification and Labelling of Chemicals), the worldwide hazard communication system.
Benefits of GHS alignment listed by CCOHS: more complete classification criteria (better at showing severity), new hazard classes, physical hazard criteria consistent with Transport of Dangerous Goods (TDG), standardized hazard and precautionary statements, standardized SDS format.

Main parts of WHMIS

Four main components: hazard identification and product classification; labelling; safety data sheets (SDSs); worker education and training.
Ontario's page puts it as three delivery methods: labels on containers, SDSs, worker education programs.

Products covered

A product covered by the Hazardous Products Act that meets the criteria of any hazard class or category is a "hazardous product".
All hazardous products used in the workplace are covered, and a WHMIS program with education and training must be in place.
Suppliers compare their products to criteria in the Hazardous Products Regulations; hazardous products must be labelled and come with an SDS at time of sale.
Hazard class and category appear in SDS Section 2 (Hazard identification) and on the supplier label.

Products not covered (exclusions)

Explosives (Explosives Act); cosmetics, devices, drugs, food (Food and Drugs Act); pest control products (Pest Control Products Act); consumer products (Canada Consumer Product Safety Act); wood and wood products; radioactive nuclear substances (Nuclear Safety and Control Act); hazardous waste (sold for recycling/recovery or intended for disposal); tobacco and tobacco products; manufactured articles.
Many of these are covered by other laws.
Even when a product is exempt from WHMIS label/SDS rules, employers must still educate and train workers on health effects, safe use and storage.

Consumer products at work

Consumer products: bought in a store, generally for home use (cleaners, adhesives, lubricants); labelled under other legislation.
Workers should still receive education and training on safe use of these products.

Generic chemical identity on an SDS

A generic chemical identity means the supplier applied to protect the exact ingredient as confidential business information (CBI); only Health Canada can approve a CBI claim.

WHMIS law and enforcement

WHMIS 1988, WHMIS 2015 and the December 2022 amendments, the Hazardous Products Act and Regulations, who enforces WHMIS in each jurisdiction and what an inspector checks.

Practise WHMIS law and enforcement questions Flashcards Official chapter

Is WHMIS law?

Yes. WHMIS first became law in 1988 through complementary federal, provincial and territorial laws ("WHMIS 1988").
Hazardous Products Regulations aligned with GHS were published in Canada Gazette Part II on February 11, 2015 ("WHMIS 2015").
Amendments to the Hazardous Products Act and Regulations came into force December 15, 2022; suppliers had a 3-year transition (CCOHS: to December 15, 2025; whmis.org: ended December 14, 2025). CCOHS now calls this "amended WHMIS" and WHMIS 2015 "former WHMIS".
Ontario page: WHMIS 2015 phased in between February 2015 and December 2018; from December 1, 2018 everyone had transitioned to WHMIS 2015.

Federal laws

Federal: Hazardous Products Act (HPA) and Hazardous Products Regulations (HPR) set supplier duties (classification, labels, SDSs). Health Canada is responsible for supplier-related laws.
Ontario guide: Hazardous Materials Information Review Act (HMIRA) and Regulations protect confidential business information; Health Canada decides whether a CBI claim is valid.
Under WHMIS 2015 "controlled products" became "hazardous products"; SDSs got a standardized 16-section format; no more 3-year SDS update rule (update as new information appears).

Workplace (employer) laws

Each province/territory and the federal government (for federally regulated workplaces) has its own occupational health and safety WHMIS rules for employers, based on a common model; small differences possible.

Who enforces WHMIS?

Enforced by provincial/territorial OHS departments or agencies, or by the federal Labour Program (ESDC) for federally regulated workplaces.
Some inspectors are designated by Health Canada to enforce supplier requirements under the HPA/HPR.
Examples from the CCOHS table: Ontario – Occupational Health and Safety Act + Regulation 860; BC – WorkSafeBC; Quebec – CNESST; federal workplaces – Canada Labour Code Part II, enforced by ESDC Labour Program.

Inspector visits

Employers should be ready to: show a WHMIS program is in place; show where SDSs are; show products have proper labels; show education and training records.
Inspectors may talk to workers to confirm training: what are the hazards, how do I protect myself, what to do in an emergency, where to get more information.
HPA inspectors may enter a place if they have reasonable grounds to believe a WHMIS-related activity is happening or a hazardous product is there.
Suppliers may be asked to show true copies of labels and SDSs in both official languages and sales/purchase records.

What all jurisdictions require of employers

Run a worker education and training program; ensure proper labels (incl. workplace labels); give access to up-to-date SDSs (prepare them if needed); have appropriate control measures.

Supplier, employer and worker duties

Who counts as a supplier, manufacturer, importer or distributor, what employers must provide, what workers must do, and the role of the health and safety committee.

Practise Supplier, employer and worker duties questions Flashcards Official chapter

Supplier, manufacturer, importer, distributor

Supplier: a person who, in the course of business, sells or imports a hazardous product.
Manufacturer: a supplier who, in business in Canada, makes, produces, processes, packages or labels a hazardous product and sells it.
Importer: a supplier who brings a hazardous product into Canada but does not sell it.
Distributor: a Canadian supplier who buys a hazardous product and resells it unchanged; if it repackages or relabels before selling, it counts as a manufacturer.
An employer that imports a hazardous product only for its own workplace is the importer and must meet supplier requirements (may keep the foreign supplier's name, address and phone on label/SDS).

Supplier duties

Classify hazardous products; provide labels; provide SDSs (at time of sale).

Employer duties

Educate and train workers on hazards and safe use.
Give workers access to up-to-date SDSs.
Make sure hazardous products are labelled; prepare workplace labels as needed.
Prepare SDSs when needed (e.g., product made and used on site).
Put appropriate control measures in place.
Program duties also include: know what hazardous products are present and how used; keep records of identity and amount; identify hazards; determine who may be exposed; develop procedures (safe use, piping/vessels, protection, emergencies); update SDSs and labels when significant new data arrives; monitor the program.
WHMIS 1988 products still on site: get a current SDS from the supplier, or author a new SDS and label, or safely dispose of the product.
Employers who produce a hazardous product on site for their own use must classify it, apply a workplace label and prepare an SDS.

Worker duties

Participate in WHMIS education and training.
Take necessary steps to protect themselves and co-workers; take part in identifying and controlling hazards.
Follow instructions and safe work procedures; know the products you handle or may be exposed to (e.g., during a spill or fire); do not use a product until trained.
Keep labels in good condition; do not use unlabelled products; ask for a new label if unreadable.
Know how to get SDSs and understand them; ask for help; report concerns.

Health and safety committee

Employer is ultimately responsible for the WHMIS program.
The program should be developed by the employer in consultation with the health and safety committee or representative.
Committees may help develop the program and training, or monitor/audit; may raise concerns found during inspections.

Elements of a WHMIS program

Six elements: purchasing and inventory; hazard identification; inspections; worker education and training; review and evaluation; document and record-keeping.
Employer must know at all times what hazardous products are present and in what amounts.
Program reviewed at least annually, or more often if conditions change. A specific WHMIS inspection at least once a year may be advisable.
Suppliers must keep documents (label and SDS copies, sales/purchase info) for six years.

WHMIS education and training

The difference between education and site-specific training, who must be trained, what it must cover, the four questions every worker should be able to answer, reviews and refreshers.

Practise WHMIS education and training questions Flashcards Official chapter

Education vs training

Education = general, portable information (how WHMIS works, hazard classes, what labels and SDSs contain). Applies in any workplace.
Training = site- and job-specific: the workplace's procedures for storage, handling, use, disposal, emergencies, spills and unusual situations.

Who must be trained

Any workplace with hazardous products must have a WHMIS program; workers must be educated and trained.
Includes workers who: may be exposed through their work (normal use, maintenance, emergencies); use, store, handle or dispose of a hazardous product; supervise or manage such workers; are involved in emergency response.
Hazard information covered = supplier information plus anything else the employer knows about use, storage and handling.

Topics

Supplier and workplace label information and meaning; SDS information and meaning; safe use, handling and disposal procedures; procedures for products in pipes, vessels, tank cars; procedures if the product may be in the air; emergency procedures.
whmis.org adds: meaning of signal words and hazard statements (e.g., "Danger. May cause cancer"), how to access SDSs, sources of more information.

Employer duties

All Canadian jurisdictions require employers to develop, implement and maintain a worker WHMIS education and training program; product-specific training for exposed workers.
Consult the health and safety committee or representative when developing/reviewing.
Review the overall program at least annually, or more often if conditions, processes or hazard information change (confirm with jurisdiction).
Most jurisdictions do not set a fixed retraining frequency.

Refresher training

Generally required: as needed to protect health and safety; when workplace conditions change; when new products are introduced; when products change and have different hazards; when new hazard information becomes available; when there is new information on safe use, handling, storage or disposal.
Some jurisdictions may require periodic evaluation of knowledge (written tests, practical demonstrations, other means). CCOHS program page: employers must periodically evaluate workers' knowledge using written tests, practical demonstrations and other means.

Worker duties

Participate in education and training; follow safe work procedures.

Changing employers

Up to the new employer whether to repeat generic education; generic part applies everywhere, but site-specific training must always be given for the new workplace and job.

Successful training

Four questions per product: What are the hazards? How do I protect myself? What do I do in an emergency? Where can I get more information?

Who delivers training

Legal obligation sits with the employer; training can be delivered by the employer or by a qualified/competent person or agency the employer chooses; employer stays legally responsible.
Employers have a choice of provider; some jurisdictions warned about high-pressure sales calls claiming the employer is non-compliant.

Hazard groups, classes and categories

The physical and health hazard groups, how classes group similar products, how categories and types show severity, and what changed in the 2022 amendments.

Practise Hazard groups, classes and categories questions Flashcards Official chapter

How classification works

Suppliers determine whether a product meets the physical and health criteria in the Hazardous Products Regulations; meeting any class criteria = hazardous product.
Employers who produce hazardous products for their own workplace must assess, classify and provide labels and SDSs.
Tools: Technical Decision Trees on whmis.org and Health Canada guidance.

Hazard groups

WHMIS has two hazard groups: physical and health.
Physical group: based on physical/chemical properties such as flammability, reactivity, corrosivity to metals.
Health group: based on ability to cause a health effect (eye irritation, respiratory sensitization, carcinogenicity).
GHS also has an environmental hazards group; WHMIS did not adopt it, but suppliers may still show environmental classes on labels and SDSs.
GHS Explosives class not in WHMIS; explosives covered by other Canadian legislation.

Hazard classes

Class = grouping of products with similar properties. Most are common to GHS; some WHMIS-specific.
19 physical hazard classes listed (incl. chemicals under pressure, combustible dusts, simple asphyxiants, physical hazards not otherwise classified).
12 health hazard classes listed (incl. biohazardous infectious materials, health hazards not otherwise classified).

Hazard categories

Every class has at least one category; categories are numbers (1, 2...); some are called types and use letters (A, B...); some subcategories (1A, 1B).
Category shows severity. Category 1 = most hazardous in that class; 1A more hazardous than 1B; Category 2 more hazardous than 3.
Examples: corrosive to metals has one category; carcinogenicity two; oxidizing liquids three; organic peroxides five or more (types).
Exceptions: Gases under pressure categories (compressed, liquefied, refrigerated liquefied, dissolved gas) describe the physical state, not severity. Reproductive toxicity has a separate "Effects on or via lactation" category without a number.

2022 amendments

New physical class: Chemicals under pressure.
"Flammable aerosols" renamed "Aerosols"; new Aerosols Category 3 for non-flammable aerosols.
Flammable gases Category 1 split into 1A and 1B; pyrophoric gases and chemically unstable gases now under Flammable gases Category 1A.

Where to find classification

Class and category in SDS Section 2 (Hazard identification) and reflected on the label.

Physical hazard classes

Flammables, oxidizers, gases under pressure, pyrophoric and self-heating products, water-reactives, organic peroxides, corrosive to metals, combustible dusts, simple asphyxiants and chemicals under pressure.

Practise Physical hazard classes questions Flashcards Official chapter

Main concerns for each physical hazard class

Flammable gases, aerosols, flammable liquids, flammable solids: ignite easily; main hazards fire or explosion. Aerosols class also has a non-flammable category (may burst when heated).
Oxidizing gases, liquids, solids: may cause or intensify a fire or cause fire/explosion.
Gases under pressure: compressed, liquefied, dissolved gases hazardous because of high pressure; container may explode if heated. Refrigerated liquefied gases are very cold and can cause cryogenic (cold) burns.
Self-reactive substances and mixtures: may react on their own to cause fire/explosion, or when heated.
Pyrophoric liquids/solids: catch fire very quickly (spontaneously) if exposed to air.
Self-heating substances: may catch fire if exposed to air, but only after a longer time or in large amounts (differs from pyrophorics).
Substances which, in contact with water, emit flammable gases: react with water to release flammable gas, sometimes igniting spontaneously.
Organic peroxides: may cause fire or explosion if heated.
Corrosive to metals: may chemically damage or destroy metals.
Combustible dusts: finely divided solid particles that may catch fire or explode if dispersed in air and ignited.
Simple asphyxiants: gases that may displace oxygen and cause rapid suffocation.
Physical hazards not otherwise classified: hazards from a chemical reaction that cause serious injury or death at the time of the reaction; hazard statement describes the hazard.
Chemicals under pressure: liquids or solids in a receptacle (not an aerosol dispenser) pressurized with a gas at 200 kPa gauge or more at 20 °C, excluding gases under pressure.

supporting facts

Fire needs fuel, oxygen and heat (ignition source) together.
Vapour of most flammable liquids is heavier than air; can travel along floor to a distant ignition source and flash back.
Static charge builds when flammable liquids are poured, pumped, filtered, stirred or flow in pipes; can ignite.
Air is about 21% oxygen. Oxidizers do not burn themselves but make fires hotter and faster and can make materials burn that normally would not.
Simple asphyxiants are colourless, odourless; low oxygen (19.5% or less) causes symptoms; concern in confined spaces. No pictogram (not in GHS); signal word Warning.
Damaged gas cylinders can rocket or spin if a valve breaks.

Health hazard classes

Acute toxicity, skin and eye damage, sensitizers, mutagens, carcinogens, reproductive toxicity, target organ toxicity, aspiration hazard and biohazardous infectious materials.

Practise Health hazard classes questions Flashcards Official chapter

Main concerns for each health hazard class

Acute toxicity: fatal, toxic or harmful if inhaled, on skin contact or if swallowed. "Acute" = effects after skin contact or ingestion of a single dose or multiple doses within 24 hours, or inhalation exposure of 4 hours. Can also come from a product that releases a toxic gas on contact with water.
Skin corrosion/irritation: severe skin burns (corrosion: ulcers, bleeding, bloody scabs) or skin irritation (reversible damage).
Serious eye damage/eye irritation: tissue damage or serious vision decay, or reversible eye irritation.
Respiratory sensitizer: may cause allergy or asthma symptoms or breathing difficulties if inhaled. Skin sensitizer: allergic response after skin contact.
Germ cell mutagenicity: may cause or suspected of causing heritable gene mutations (passed to future generations).
Carcinogenicity: may cause cancer or increase its incidence.
Reproductive toxicity: damage to sexual function and fertility, harm to the unborn child, or effects on or via lactation (harm to breast-fed children).
STOT single exposure: organ damage (e.g., liver, kidneys, blood) after one exposure; includes a category for respiratory irritation or drowsiness/dizziness.
STOT repeated exposure: organ damage after prolonged or repeated exposure.
Aspiration hazard: liquid or solid enters the trachea/lower airways via mouth or nose or by vomiting; can cause chemical pneumonia, lung injury, death.
Biohazardous infectious materials: microorganisms, nucleic acids or proteins that cause or probably cause infection in humans or animals.
Health hazards not otherwise classified: other adverse health effects after acute or repeated exposure; hazard statement describes it.

Hazard statements (wording shows degree)

"May cause cancer" (Category 1, Danger) is more hazardous than "Suspected of causing cancer" (Category 2, Warning).
Acute toxicity: Categories 1-2 "Fatal if...", Category 3 "Toxic if...", Category 4 "Harmful if..." (Warning, exclamation mark).

Exclamation mark / Biohazardous infectious materials

Skin sensitization: often no reaction the first time; skin reacts on later exposures. Latex and nickel are common skin sensitizers.
Eye irritation Category 2/2A: reversible effects within 21 days.
Biohazardous infectious materials for WHMIS = Risk Groups 2, 3 or 4 under the Human Pathogens and Toxins Act. Risk Group 4 example: Ebola virus. Found in hospitals, labs, vet practices, research.

WHMIS pictograms

The red-bordered diamond pictograms described in words: flame, flame over circle, gas cylinder, corrosion, exploding bomb, skull and crossbones, health hazard, exclamation mark and the biohazard symbol, plus classes with no pictogram.

Practise WHMIS pictograms questions Flashcards Official chapter

What is a pictogram?

A graphic image showing at a glance the type of hazard. Most have a red border shaped as a square set on one of its points (a diamond) with a black symbol inside. Symbol + border = pictogram. Pictograms are assigned to specific classes/categories.
Found on supplier labels and on SDSs (as the symbol or the name of the symbol, SDS Section 2).

Pictogram names and what they signal (CCOHS chart)

Exploding bomb: explosion or reactivity hazards (self-reactives and organic peroxides Types A and B).
Flame: fire hazards (flammable gases, aerosols Cat 1-2, flammable liquids Cat 1-3, flammable solids, pyrophorics, self-heating, water-reactives, self-reactives/organic peroxides Types B-F, chemicals under pressure Cat 1-2).
Flame over circle: oxidizing hazards (oxidizing gases, liquids, solids). The circle is an "o" for oxygen.
Gas cylinder: gases under pressure (all four categories), chemicals under pressure.
Corrosion: corrosive damage to metals, skin and eyes (symbol: liquid dripping from containers onto metal and onto a hand). Corrosive to metals Cat 1; skin corrosion Cat 1; serious eye damage Cat 1.
Skull and crossbones: death or toxicity with short exposure to small amounts; acute toxicity Cat 1-3 (oral, dermal, inhalation).
Health hazard: may cause or is suspected of causing serious health effects (symbol: silhouette of head and chest with a star-shaped burst on the chest). Respiratory sensitizer, germ cell mutagenicity, carcinogenicity, reproductive toxicity, STOT single (Cat 1-2) and repeated, aspiration hazard.
Exclamation mark: less serious health effects (acute toxicity Cat 4, skin irritation Cat 2, eye irritation Cat 2/2A, skin sensitizer, STOT single Cat 3) or damage to the ozone layer (GHS environmental, optional).
Environment (dead tree and fish): GHS environmental pictogram, not required in WHMIS but may appear.
Biohazardous infectious materials: organisms or toxins that can cause disease in people or animals. Symbol is three joined "c" shapes with a small circle in the middle; border is a black circle (not a red diamond).

Two pictograms on one class

Self-reactives and organic peroxides Type B: both flame and exploding bomb.
Chemicals under pressure Cat 1 and 2: both flame and gas cylinder.
Physical/health hazards not otherwise classified must use a GHS pictogram appropriate to the hazard.

Classes and categories with no pictogram

Aerosols Cat 3; flammable gases Cat 2; flammable liquids Cat 4; self-reactives and organic peroxides Type G; combustible dusts; simple asphyxiants; eye irritation Cat 2B; reproductive toxicity effects on or via lactation.
Label and SDS Section 2 still need signal word, hazard statements, other elements.

Supplier labels

The required parts of a supplier label, the two signal words, hazard and precautionary statements, bilingual rules, small-container exemptions and the 180-day update rule.

Practise Supplier labels questions Flashcards Official chapter

Purpose and responsibility

Labels are the first alert to the user about major hazards and basic precautions.
Suppliers label the hazardous products they provide; labels must be affixed to, printed on or attached to the product/container and stay legible. A label sent only with shipping papers does not comply.
Employers make sure incoming hazardous products are labelled.
If a product is always used from the container with the supplier label, no other label is needed.

Required supplier label elements

Product identifier (brand, chemical, common, generic or trade name).
Initial supplier identifier: name, address and phone of the Canadian manufacturer or Canadian importer (exceptions: distributor may substitute its own details; employer importing for own use may keep foreign supplier details).
Pictogram(s); signal word; hazard statement(s); precautionary statement(s); supplemental label information (e.g., % of ingredients with unknown toxicity when ≥ 1%).
Must be in English and French: one bilingual label or two labels. English-only or French-only does not comply.
No set format, but pictogram, signal word and hazard statements must be grouped together; clearly and prominently displayed; easy to read without aids except corrective glasses; contrast with other information.
Hatched border from WHMIS 1988 no longer required (allowed). Hazardous ingredients no longer required on the label (they are on the SDS).

Signal words

Only two: "Danger" (high-risk / more severe) and "Warning" (less severe). Some classes/categories have no signal word.

Hazard statements

Standardized phrases describing the nature/degree of the hazard (e.g., "Extremely flammable gas", "Fatal if inhaled", "May cause cancer").

Precautionary statements

Standardized advice to minimize or prevent harm; five types: general, prevention, response (incl. first aid), storage, disposal.
Slash (/) in GHS guidance means the supplier picks the right items (e.g., "Wear protective gloves/eye protection"); dots (...) mean add other relevant conditions.

Updating supplier labels

Update within 180 days of becoming aware of "significant new data" (data that changes classification/category, adds a class, or changes how to protect against the hazard). If sold during that period, supplier provides written changes and date.
Employers who receive significant new data from a supplier must update the relevant supplier labels.

Small containers and multiple containers

100 mL or less: exempt only from precautionary and hazard statements.
3 mL or less: if the label interferes with normal use, label must be durable for transport/storage but may be removable during use.
Bulk shipments: labelling exemption for products sold without packaging.
Fold-out/accordion labels allowed if space is short.
Multiple containers: each container fully labelled, unless inner label visible through outer, or outer container has TDG label (not if outer is the only container).

Worker steps

Check for a label before use; read and follow label and SDS; ask for a new label if unreadable; do not use unlabelled products.

Workplace labels and other identification

When a workplace label is needed (decanting, products made on site, lost labels), the decanting exceptions, what a workplace label must say, and other means of identification.

Practise Workplace labels and other identification questions Flashcards Official chapter

When a workplace label is required

When a hazardous product is produced (made) at the workplace and used there.
When it is decanted (transferred, poured) into another container.
When a supplier label is lost or becomes illegible.

When a workplace label is not necessary

Product poured into a container and used immediately.
Product "under the control of the person who decanted it": the person who poured it is the only user and it is used within one shift — a full workplace label may not be needed, but the container must still show the product identifier (name).
If not used right away, or more than one person controls it, a full workplace label is required.
Companies may set stricter rules than WHMIS; workplace label rules are set by the province/territory (or Canada Labour Code for federal workplaces).

Workplace label content

Product name matching the SDS; safe handling precautions (may include pictograms or other supplier label information); a reference to the SDS if available.
Ontario guide adds: no fixed format/language; precautions may be in pictures, words, pictograms, combined with worker education.

Other identification

Products can also be identified with a mark, sign, stamp, sticker, seal, ticket, tag or wrapper (attached, imprinted, stencilled, embossed). Workers must be trained on any such alternative system.

Inspections checklist (labels)

Containers and labels in good condition; no unlabelled hazardous products; decanted products not used immediately by the person who decanted them have workplace labels; vessels and pipelines labelled per WHMIS; SDS and label information match.

Pipes, vessels, placards (for context)

Products in pipes, process/reaction vessels, tank cars etc.: identified by any clear means (colour coding, labels, placards, piping diagrams, signs) plus worker education.
Placard allowed for products not in a container etc.; placard carries workplace label information.

Safety data sheets (16 sections)

What an SDS is, the 16 sections in their required order, which sections workers use most, update rules, and the employer's duty to keep SDSs available.

Practise Safety data sheets (16 sections) questions Flashcards Official chapter

What is an SDS?

Summary document on a product's hazards and safety precautions; usually written by manufacturer/supplier; must be provided by the supplier at the time of sale. Employer may have to prepare one (product made and used exclusively in that workplace).
More detailed than the label. Tells users the hazards, safe use, what happens if advice is not followed, symptoms of exposure, what to do in emergencies.
Every hazardous product for use, handling or storage in a Canadian workplace must have an SDS.
Must be in English and French (one bilingual SDS or two; if two, both given at same time).

The 16 sections (required order)

Emergency phone number need not be Canadian; restrictions (hours, language) must be stated.

Delivery and updates

Supplier gives SDS on paper or electronically (email attachment, USB). Only giving a website link is not acceptable.
Supplier must update within 90 days of becoming aware of significant new data; no more 3-year update rule (WHMIS 1988). Not required to send updates to past buyers.
Employer side varies: Ontario, Alberta, Manitoba, NB, PEI, Quebec — update within 90 days when significant new info; federal, BC, SK, NL, NWT, NS, NU, YT — employer must seek updated SDS every three years.
Check Section 16 revision date to see if an SDS has been updated.

Employer duties

Every hazardous product has an up-to-date SDS when it enters the workplace; readily available to exposed workers and the health and safety committee/representative.
Electronic SDS allowed if all workers have access and are trained, devices kept working, and paper copy provided on request.

Using an SDS

Four purposes: identification, hazards, prevention, response.
Workers should always: read name (Section 1), know hazards (Section 2), understand handling and storage (Section 7), know emergency steps (Sections 4, 5, 6).
Match product name on container to SDS Section 1; check intended use matches Section 1, else ask supervisor.
"Not available" = information could not be found or does not exist; "Not applicable" = not relevant (e.g., odour of an odourless product). Avoid undefined "n.a."
SDS may not be specific to your workplace (e.g., says a respirator is needed but not which type) — ask supervisor.

Safe handling and storage

Everyday precautions by pictogram: ventilation, ignition sources, incompatibles, gas cylinders, corrosives, toxic products, storage height, cabinets and controls such as substitution and PPE.

Practise Safe handling and storage questions Flashcards Official chapter

all pictograms (common steps)

Check the SDS for ALL hazards and precautions; ask if unsure.
If the product cannot be eliminated, consider substituting a less hazardous one.
Use the smallest amount needed; use in well-ventilated areas; keep containers closed when not in use.
If PPE is required, the employer must ensure workers are trained in its selection, fit, use and maintenance; SDS guides selection.
Report leaks, spills and failures of safety equipment (e.g., ventilation) immediately.
Do not eat, drink or smoke in work areas (toxic/health/oxidizer pages); wash hands after handling.
Inform maintenance staff of hazards before they start work.
Empty containers may hold hazardous residue; store separately, keep closed; do not reuse (corrosion/health hazard pages).

Workplace controls (checklist)

Substitution of a less hazardous product; engineering controls (local exhaust ventilation, process change); administrative controls (procedures, scheduling); PPE and clothing.

handling and storage

Keep away from heat, hot surfaces, sparks, open flames; no smoking; watch hidden ignition sources (pilot lights).
Aerosols: do not spray on flame; do not pierce or burn even after use; do not expose to temperatures over 50 °C (122 °F); protect from sunlight.
Volatile flammable liquids: non-sparking tools, explosion-proof equipment, prevent static (ground and bond containers).
Remove combustibles (oily rags, cardboard); no hot work on empty containers until all traces removed.
Store in flammable storage cabinets/fridges/safety cans; avoid large quantities; ground floor preferred over basements.

handling and storage

Keep away from combustibles (wood, paper, rags), greases, lubricants, solvents, paints.
Gas valves and fittings free of oil and grease.
Never return unused product to original container.
Do not use wooden or combustible pallets; storage area built of non-combustible materials; store separately, cool, dry, away from sunlight and exit paths.

handling and storage

Always wear eye protection (chemical safety goggles); sometimes a face shield.
Inspect cylinders and valves; never open a damaged valve; use the right regulator; no homemade adaptors.
Secure cylinders upright to a wall or rack; keep cap on until secured and ready to use; close valves when not in use.
No lubricant, joint compound or tape on valves/fittings/regulator threads; keep oil and grease away.
Move with a hand truck or cart; do not drop or bang.
Refrigerated liquefied gases: cold-insulating gloves, face shield or eye protection; no watches, rings or bracelets.
Store upright, secured, cap on, away from exits, out of sunlight, well ventilated; first-in, first-out.

handling and storage

Keep in original packaging; use corrosion-resistant equipment.
Never add water to the corrosive; when diluting, add corrosive slowly to cold water in small amounts, stirring.
Move drums with drum cradles; carboy caddies and bottle carriers for smaller containers.
Store below eye level if possible; trays of compatible material; corrosive storage cabinets for large amounts — flammable storage cabinets are NOT corrosion-resistant.
First in, first out; mark date received and date opened.

handling and storage

Avoid dry sweeping toxic solids; pre-wet or use HEPA-filtered vacuum.
Sometimes do not work alone with acute toxicity products.
Remove contaminated clothing and PPE before entering eating areas.
Carcinogens, mutagens, reproductive toxins: get special instructions before use; do not handle until all precautions read and understood.
Store health hazard products low (avoid above eye level), restrict access, consider locked storage.
Skin sensitizers: contaminated work clothing should not leave the workplace.

Exploding bomb / Simple asphyxiants

Exploding bomb products: keep cool, keep only in original packaging, ground and bond; do not use if appearance doesn't match SDS or age is unknown.
Simple asphyxiants: do not carry in an enclosed space (elevator, inside a vehicle); do not work alone; check oxygen levels before entering confined areas; avoid bulk storage indoors.

Emergencies, spills and first aid

Where emergency information is on the SDS, reporting leaks and spills, fire and evacuation basics, eyewash and showers, and standard first-aid steps by route of exposure.

Practise Emergencies, spills and first aid questions Flashcards Official chapter

Emergency information (CCOHS SDS fact sheet)

Section 4 first aid; Section 5 fire-fighting; Section 6 accidental release; Section 1 emergency phone number (may be non-Canadian; restrictions such as hours or language stated). Section 2 summarizes what to do in an emergency.
Precautionary "response" statements on the label include first aid; e.g., "If exposed or concerned: Get medical advice/attention."

emergency steps common to all pictograms

Understand and practise emergency procedures before you need them.
Eyewash and emergency shower readily available in the immediate work area; tested regularly.
Spill control procedures and equipment ready (absorbents, PPE, non-sparking tools where needed).
Immediately report leaks to your supervisor, warn people in the area, move to a safe location if necessary.
Know at least two exit paths in case of fire; appropriate fire extinguishers available.
Do not use combustible materials (paper towels, sawdust) to absorb flammable or oxidizer spills.
Remove contaminated clothing; flammable-soaked clothing and leather shoes/boots are a fire hazard; wash before re-wearing.

First aid by route (precautionary wording, corrosion/skull/health hazard pages)

If inhaled: move person to fresh air, keep comfortable for breathing; call Poison Centre or doctor as directed.
If on skin (or hair): take off contaminated clothing immediately; rinse skin with water or shower; wash clothing before reuse.
If in eyes: rinse cautiously with water for several minutes; remove contact lenses if present and easy; continue rinsing.
If swallowed (corrosive, aspiration hazard): rinse mouth; do NOT induce vomiting; call Poison Centre or doctor.
Refrigerated liquefied gas contact: thaw frosted parts with lukewarm water; do not rub; get medical attention.
Oxidizer on clothing: rinse contaminated clothing and skin with plenty of water before removing clothes.
Toxic products: have medical response ready (antidotes, copy of SDS for the doctor/first responders).

Fire and explosion

Oxidizers/Type B self-reactives: in major fire, evacuate, fight fire remotely due to explosion risk.
Type A (exploding bomb): evacuate; do not fight fire when it reaches the product.
Gas fire: stop the leak if safe to do so.

Toxic or asphyxiant releases

Spill of acute toxicity product or asphyxiant leak: put on an escape-type respirator if required and exit the area.
Oxygen deficiency rescue: protect yourself first (proper equipment) before attempting rescue; move victim to fresh air; call Poison Centre/doctor.

emergencies

Assume tissue, blood or body fluids are infectious; cover cuts and wear gloves; be careful with sharps; wash hands; sanitize; report exposures to the designated person.

emergency procedures

Review first-aid, spill and firefighting procedures; notify the local fire department of the location, types and quantities of hazardous products.

Ontario WHMIS rules (Regulation 860)

How Ontario applies WHMIS through the Occupational Health and Safety Act and Regulation 860: who is covered, decanted containers, SDS access, annual review of training, exemptions and hazardous waste.

Practise Ontario WHMIS rules (Regulation 860) questions Flashcards Official chapter

Ontario's WHMIS legislation

Ontario WHMIS rules are in the Occupational Health and Safety Act (OHSA) and the WHMIS Regulation (R.R.O. 1990, Regulation 860).
Applies to all workplaces covered by the OHSA except farms.
Ontario's labour ministry enforces both federal (HPA, HPR) and provincial WHMIS law in Ontario workplaces, so employers are not inspected twice.
Federally regulated workplaces in Ontario (banks, post offices, airports) are covered by the Canada Labour Code instead.
WHMIS applies inside workplaces; products being transported and handled under TDG law are exempt. A trans-shipment warehouse storing unchanged goods for transport falls under TDG; repackaging/using in a warehouse can bring WHMIS in.

WHMIS and the worker

Right to know is one of three basic worker rights under the OHSA.
Workers have access to labels, SDSs and training; through the JHSC/HSR they have the right to be consulted on WHMIS training.
Ministry supports workers training other workers where appropriate.
Worker should: read and follow labels and SDSs; follow procedures incl. PPE; take part in training; ask a supervisor if unsure; report contraventions or hazards (e.g., missing SDS for a new product, unreadable label).

General duties and exception

Ensure products are identified; obtain or prepare current SDSs and make them available; ensure exposed workers get instruction and training; assess agents produced for own use.
May store (not use) a product without label/SDS/training while actively seeking supplier label and SDS; must notify the ministry in writing if unable to obtain them after reasonable efforts.
No one may remove or deface identification on a hazardous product.

Labels

Every product from a supplier must have a supplier label; if lost/illegible, replace with new supplier label or workplace label.
Employer may not alter a supplier label while product remains in the supplier container.
Supplier label may be removed from a container of 3 mL or less if it interferes with normal use.
Bulk shipment: e.g., vessel with water capacity of 450 litres or more, freight container, tank, ship hold, pipeline.
Workplace label: product identifier identical to SDS; safe handling information (pictures, words, pictograms); statement that an SDS is available (if one exists).
Decanted: workplace label needed unless (a) all of it is for immediate use, or (b) used only by the worker who filled it, only during that shift, and contents clearly identified.
Piping systems, vessels, tank cars: any clear means of identification understood by workers (colour coding, labels, placards, diagrams) plus education.

SDSs

Employer-produced product SDS: update as soon as practicable but no later than 90 days after significant new data.
SDSs must be readily available to exposed workers, close to them and accessible every shift — not in a remote office or one locked at night. Electronic copies are acceptable (no paper required).
Must also be available to the JHSC/HSR; employer consults them on how to make SDSs available.
Public can access SDSs through the local medical officer of health.

Worker education

Program must cover: label information; other modes of identification; SDS information; procedures for safe use, storage, handling, disposal; procedures for pipes/vessels; procedures for fugitive emissions; emergency procedures.
Developed in consultation with JHSC/HSR. No specific requirement to keep training records (but useful).
Employer must review workers' training at least once a year, in consultation with JHSC/HSR; more often if JHSC/HSR advises or circumstances change. Review does not automatically mean retraining.
Evaluation method left to the employer (written/oral test, practical demonstration).
Ministry position: time spent in training is work time and should be paid.
Exposed worker includes one who directly supervises others using the product; "likely to be exposed" includes risk during maintenance or emergencies.

Exemptions

Complete exemption: wood/wood products; tobacco; manufactured articles; products being transported/handled under TDG law.
Partial exemption (no WHMIS label/SDS, but training still required): explosives, cosmetics/devices/drugs/food, pest control products, radioactive nuclear substances, consumer products.
Hazardous waste: safe storage and handling through identification (colour coding, sign "Caution — Hazardous Waste", picture sign) plus education; no label or SDS required.
Fugitive emissions and intermediates in a reaction vessel: no label, identification or SDS required.

Written in our own words from: CCOHS OSH Answers: WHMIS fact sheets

FAQ

WHMIS study guide: common questions

What is the best way to use this WHMIS study guide?

Read one topic, then answer that topic's practice questions while the rules are fresh. Note the questions you miss, re-read those notes, and finish with a full practice test across all 14 topics.

Is this the official WHMIS handbook?

No. It is our own summary of the CCOHS OSH Answers: WHMIS fact sheets. Use it to review, and use the official handbook when you need the exact wording of a rule.

Can I print the study guide?

Yes, with your browser's print command. For practice questions on paper with an answer key, use our printable questions and answers page instead.