1. HAZARD CLASSIFICATION

2. Hazard Classification-3 Levels- Grouping products with
Hazard Group (Physical or Health)
Hazard Class (eg. flammable, biohazard)
Hazard Categories (1 to 4)
Hazard classes are a way of grouping together products that have similar properties. Most of the hazard classes are common to GHS and will be used worldwide by all countries that have adopted GHS. Some hazard classes are specific to WHMIS 2015.
The requirements for pictograms are based on severity of the hazard. In some cases no pictogram is required.
Refer to Fact Sheet on Hazard Classes
Classification is based on test data on individual chemicals or mixture of chemicals
Once classification is established the wording of the hazard and precautionary statements is fixed for the classification

3. Changes to Classification
Classification criteria has changed in WHMIS. Some new classes will be added.
See the WHMIS Hazard Classes Infosheet for more information.
The GHS applies not only to workplaces but also workplace chemicals during
transport and consumer chemicals. The system has two major elements:
Classification of chemical hazards. The GHS sets rules or criteria for classifying
both pure chemicals and mixtures. Within this classification system, there
are three major hazard groups:
• Physical hazards;
• Health hazards; and
• Environmental hazards.
Within each of these hazard groups, there are “classes” and “categories.” For
example, criteria have been developed for classifying chemicals for the following:
• Physical hazard classes: flammable liquids, solids and gases; oxidizing
liquids, solids and gasses; and explosive substances;
• Health hazard classes: acute toxicity, cancer, skin irritation/corrosion, reproductive toxicity and aspiration hazard; and
• Environmental hazard class: hazardous to the aquatic environment (criteria
for the hazardous to the terrestrial environment class are under
development).

4. Physical Hazard Classes
Products put in this group based on their physical or chemical properties
Flammability
Reactivity
Combustible Dusts
Corrosive to Metals
Physical hazards group: based on the physical or chemical properties of the product - such as flammability, reactivity, or corrosivity to metals.
Flammables (classes -gases, aerosols, liquids and solids)- Burn if ignited by a source of ignition- e.g gasoline, some cleaners,
Oxidizers (3 classes –gases, solids, solids) – cause materials to burn more readily-e.g. nitric acid spilled on clothing
Gases under Pressure (liquefied, chilled or dissolved) –may act as torpedo if dropped
Corrosive to Metals- can damage metals e.g. sodium hydroxide, hydrochloric acid
Self Reactive substances/mixtures- unstable materials that cause or increase fire intensity
Organic Peroxides- Unstable and highly reactive or explosive
Combustible Dusts- may explode on ignition
Simple Asphyxiants-displace oxygen
Physical Hazards not otherwise classified

5. Health Hazards Classes
Products put in this group based on their ability cause a health effect.
Skin/eye or lung irritation
Serious eye damage
Cancer
Birth defects
Organ damage
Gnerally Things that cause disease or illness to body

6. Compressed Gas Cylinder
Compressed, liquefied, dissolved gases
Gases under pressure can explode if heated or dropped
E.g. propane; fire extinguisher
Keep away from heat
Do not drop

7. Flame
Flammable gases, aerosols, liquids solids, self heating, organic peroxides
Capable of catching fire with heat source
E.g. Gasoline

8. Oxidizer-Flame Over Circle
Materials that provide oxygen.
Increase risk of fire if they come in contact with flammable or combustible materials.
E.g. Hydrogen Peroxide

9. Skull & Crossbones-Acute Toxicity
Toxic-potentially fatal health effects
May cause permanent damage if inhaled, swallowed, or on skin/eye contact – E.g. graffiti removers, chlorine; rat poison
Materials we would normally think of as poisons, materials that can cause rapid injury or death

10. Skin/Eye/lung Irritation Allergic Reactions Drowsiness
Exclamation Mark
Irritants
Skin/Eye/lung Irritation
Allergic Reactions
Drowsiness
Uses the Exclamation Mark Pictogram
Products that can cause allergic reactions
Signal word is Warning and hazard statement is
“May cause an allergic skin reaction”
E.g. Methyl Methacrylate used for acrylic nails

11. Health Hazard
May cause serious health problems as a result of single or repeated exposure over time
Cancer, birth defects, or sterility, liver or nerve damage
E.g. Lead, asbestos, solvents
May cause serious and health problems as a result of repeated exposure over time (e.g. nerve or liver damage)
Irritant to skin, eyes, or respiratory system;
May cause cancer, birth defects, or sterility
(Solvents, asbestos; dioxins, lead)
Carcinogen
Mutagenic
Reproductive toxin
Respiratory Sensitizer
Specific organ toxicity-single or repeated exposure
Aspiration hazard

12. Corrosive Materials that damage or eat through metals or skin/lungs.
Products can cause severe irritation, skin burns and eye damage
E.g. bowl cleaners, floor strippers, laundry detergents

13. Exploding Bomb- Explosive
Self reactive substances and mixtures
May explode or produce toxic gas when dropped, exposed to water or other substances or improperly stored- e.g. Organic Peroxides
Materials which may self react dangerously (e.g. explode or produce toxic gas) upon standing or when exposed to water, physical shock or increased or pressure
E.g. acetylene; cyanides

14. Biohazardous/Infectious Materials
Only pictogram that is carried over from the old WHMIS
Potential to cause disease in people
Eg. Blood, viruses