WHMIS Hazard Classes and Symbols 3 — Questions and Answers
Question 1: The 'health hazard' pictogram (silhouette with a starburst on the chest) is used for which conditions?
- Skin and eye irritation only
- Carcinogens, mutagens, reproductive toxins, sensitizers, and STOT-repeated exposure (Correct answer)
- Acute fatal toxicity
- Corrosive substances
Correct answer: Carcinogens, mutagens, reproductive toxins, sensitizers, and STOT-repeated exposure
The health hazard pictogram covers serious long-term effects: carcinogenicity, mutagenicity, reproductive toxicity, respiratory sensitization, and STOT-repeated exposure.
Question 2: Under WHMIS 2015, 'corrosive to metals' is classified as which type of hazard?
- Health hazard
- Physical hazard (Correct answer)
- Environmental hazard
- Biohazard
Correct answer: Physical hazard
Corrosive to metals is categorized as a physical hazard because the primary concern is damage to materials and equipment, not human tissue.
Question 3: Which of the following is NOT a category under 'flammable liquids' in WHMIS 2015?
- Flash point below 23°C and initial boiling point ≤35°C
- Flash point below 23°C and initial boiling point >35°C
- Flash point ≥23°C and ≤60°C
- Flash point above 93°C (Correct answer)
Correct answer: Flash point above 93°C
Flammable liquids in WHMIS 2015 have flash points at or below 60°C; liquids with flash points above 93°C fall outside this hazard class.
Question 4: What shape are all WHMIS 2015 GHS-aligned pictogram borders?
- Circle
- Square
- Diamond (square on point) (Correct answer)
- Hexagon
Correct answer: Diamond (square on point)
WHMIS 2015 pictograms use a red-bordered diamond shape (square rotated 45°) with a white background and black symbol, aligning with GHS international standards.
Question 5: A product labelled with both the 'exploding bomb' and 'flame' pictograms most likely belongs to which class?
- Compressed gas and flammable liquid
- Organic peroxides (which can be both explosive and flammable) (Correct answer)
- Oxidizer and pyrophoric solid
- Corrosive and flammable solid
Correct answer: Organic peroxides (which can be both explosive and flammable)
Organic peroxides can exhibit both explosive decomposition and flammability, so they may carry both the exploding bomb and flame pictograms.
Question 6: Which WHMIS 2015 hazard class specifically covers substances that react violently with water to release flammable gas?
- Oxidizing liquids
- Substances that in contact with water emit flammable gases (Correct answer)
- Self-reactive substances
- Pyrophoric liquids
Correct answer: Substances that in contact with water emit flammable gases
The class 'substances that in contact with water emit flammable gases' (water-reactive substances) covers materials like sodium metal that produce hydrogen gas on contact with water.
Question 7: Under WHMIS 2015, 'simple asphyxiants' such as nitrogen or argon are classified as which hazard type?
- Acute toxicity
- Physical hazard — simple asphyxiant (WHMIS-specific class) (Correct answer)
- Health hazard — STOT single exposure
- Gases under pressure only
Correct answer: Physical hazard — simple asphyxiant (WHMIS-specific class)
Simple asphyxiants are a WHMIS-Canada-specific physical hazard class for gases that can displace oxygen in the air and cause suffocation without being chemically toxic.
WHMIS Hazard Classes and Symbols 3
The 'health hazard' pictogram (silhouette with a starburst on the chest) is used for which conditions?