WHMIS Hazard Classes and Symbols 4

Question 1

Which WHMIS 2015 class covers thermally unstable substances that can undergo exothermic decomposition without an oxidizer?

Accepted Answer

Self-reactive substances

Answer

Self-reactive substances are thermally unstable and can decompose exothermically even without oxygen, unlike explosives which require initiation.

Question 2

In WHMIS 2015, what distinguishes a Category 1 hazard from a Category 2 hazard within the same class?

Accepted Answer

Category 1 is more hazardous (most severe); Category 2 is less hazardous

Answer

In WHMIS 2015 (GHS), lower category numbers indicate greater hazard severity; Category 1 is always the most severe within a class.

Question 3

Which combination of pictograms would appear on a strong acid like concentrated sulfuric acid?

Accepted Answer

Corrosion + exclamation mark (or skull and crossbones depending on concentration)

Answer

Concentrated sulfuric acid carries the corrosion pictogram for skin/metal corrosion and may carry skull and crossbones or exclamation mark based on acute toxicity category.

Question 4

Which WHMIS 2015 health hazard class specifically applies to substances that damage lung tissue if accidentally swallowed and aspirated?

Accepted Answer

Aspiration hazard

Answer

Aspiration hazard covers liquids (like hydrocarbons) that can enter the lungs during ingestion or vomiting, causing severe pulmonary damage or death.

Question 5

The 'environment' pictogram (dead fish and tree) in WHMIS 2015 is used for substances with what property?

Accepted Answer

Acute or chronic aquatic toxicity

Answer

The environment pictogram indicates aquatic toxicity — substances acutely or chronically hazardous to aquatic organisms such as fish, algae, and invertebrates.

(WHMIS) Workplace Hazardous Materials Information System Practice Test

(WHMIS) Workplace Hazardous Materials Information System Practice Test

WHMIS Hazard Classes and Symbols 4