WHMIS Safe Handling and Exposure 2 — Questions and Answers
Question 1: Under WHMIS, which action is required before using a hazardous product for the first time?
- Read the Safety Data Sheet (SDS) (Correct answer)
- Ask a coworker how they use it
- Estimate the risk based on the product's color and smell
- Check if the container is sealed
Correct answer: Read the Safety Data Sheet (SDS)
Workers must read the SDS before using a hazardous product to understand its hazards and safe handling requirements.
Question 2: A worker is transferring a flammable solvent into a smaller container. What WHMIS-required step must be completed on the new container?
- Apply a workplace label with product name, hazard info, and safe handling instructions (Correct answer)
- Leave it unlabeled if used within the same shift
- Write only the product name in marker
- Attach the original supplier label to the new container
Correct answer: Apply a workplace label with product name, hazard info, and safe handling instructions
Decanted hazardous products must have a workplace label that includes the product identifier, hazard information, and safe handling precautions.
Question 3: Which of the following best describes an 'exposure limit' for a hazardous product?
- The maximum concentration in air a worker can be exposed to without adverse health effects (Correct answer)
- The highest temperature at which a chemical is stored
- The amount of PPE required per shift
- The number of hours allowed in a hazardous area per week
Correct answer: The maximum concentration in air a worker can be exposed to without adverse health effects
An exposure limit (such as a TLV or OEL) defines the maximum airborne concentration considered safe for workers over a given time period.
Question 4: When handling a corrosive substance listed under WHMIS, which route of exposure is MOST commonly associated with skin and eye damage?
- Direct contact (Correct answer)
- Inhalation
- Ingestion
- Injection
Correct answer: Direct contact
Corrosive substances primarily cause damage through direct skin and eye contact, making protective equipment essential.
Question 5: An SDS lists a substance as having a TWA (Time-Weighted Average) of 50 ppm. What does this mean for a worker on an 8-hour shift?
- The average exposure over 8 hours should not exceed 50 ppm (Correct answer)
- The worker can be exposed to 50 ppm for up to 15 minutes only
- 50 ppm is the immediately dangerous concentration
- The substance must be used in ventilated areas only above 50 ppm
Correct answer: The average exposure over 8 hours should not exceed 50 ppm
A TWA of 50 ppm means the average airborne concentration over an 8-hour workday should not exceed that level.
Question 6: A WHMIS-classified 'skin sensitizer' product was spilled on a worker's glove. The worker has no immediate reaction. What is the correct response?
- Remove and replace the glove immediately and wash the affected skin (Correct answer)
- Continue working since there is no immediate reaction
- Apply a barrier cream and continue working
- Only change gloves at the end of the shift
Correct answer: Remove and replace the glove immediately and wash the affected skin
Skin sensitizers can cause allergic reactions upon repeated exposure; immediate decontamination prevents sensitization even without an immediate reaction.
Question 7: Which engineering control is MOST effective at reducing inhalation exposure to hazardous vapors under WHMIS guidelines?
- Local exhaust ventilation (LEV) installed at the source (Correct answer)
- General dilution ventilation in the room
- Respiratory protective equipment worn by workers
- Administrative rotation of workers in the hazardous area
Correct answer: Local exhaust ventilation (LEV) installed at the source
Local exhaust ventilation captures vapors at the source before they disperse, making it the most effective inhalation control.
