STSC Health Hazards and Hygiene 5 — Questions and Answers
Question 1: Under the OSHA Hazard Communication Standard, what must a Safety Data Sheet (SDS) Section 8 specifically contain?
- First aid measures and antidotes
- Exposure limits and engineering controls (Correct answer)
- Physical and chemical properties
- Ecological toxicity information
Correct answer: Exposure limits and engineering controls
SDS Section 8 (Exposure Controls/Personal Protection) lists occupational exposure limits, engineering controls, and required PPE.
Question 2: A construction site is near a former dry-cleaning facility. Workers should be most concerned about exposure to which contaminant in soil and groundwater?
- Asbestos fibers
- Tetrachloroethylene (PCE/PERC) (Correct answer)
- Lead paint chips
- Crystalline silica
Correct answer: Tetrachloroethylene (PCE/PERC)
Dry-cleaning facilities historically used tetrachloroethylene (perchloroethylene), a chlorinated solvent that persists in soil and groundwater and is a probable human carcinogen.
Question 3: What is the purpose of biological monitoring in occupational health programs on construction sites?
- To test air quality in the work environment
- To measure the actual amount of a hazardous substance absorbed into a worker's body (Correct answer)
- To evaluate the effectiveness of engineering controls only
- To determine surface contamination levels on equipment
Correct answer: To measure the actual amount of a hazardous substance absorbed into a worker's body
Biological monitoring measures chemicals or their metabolites in blood, urine, or breath to assess actual worker body burden regardless of the route of entry.
Question 4: Which heat illness requires immediate emergency medical response and is characterized by hot, dry or moist skin, confusion, and loss of consciousness?
- Heat cramps
- Heat syncope
- Heat exhaustion
- Heat stroke (Correct answer)
Correct answer: Heat stroke
Heat stroke is a life-threatening emergency where the body's thermoregulation fails, causing core temperature to rise dangerously and affecting brain function.
Question 5: When must a construction employer provide a medical examination under OSHA's lead standard (29 CFR 1926.62)?
- When a worker requests it
- When a worker is exposed above the action level of 30 µg/m³ for more than 30 days per year (Correct answer)
- Annually for all workers on lead projects regardless of exposure
- Only after a worker shows symptoms of lead poisoning
Correct answer: When a worker is exposed above the action level of 30 µg/m³ for more than 30 days per year
Medical surveillance under the OSHA lead standard is triggered when workers are exposed above the action level (30 µg/m³ as an 8-hr TWA) for more than 30 days per year.
Question 6: What is the correct order of the hierarchy of controls for managing occupational health hazards on a construction site?
- PPE → Administrative → Engineering → Substitution → Elimination
- Elimination → Substitution → Engineering → Administrative → PPE (Correct answer)
- Administrative → Engineering → Elimination → PPE → Substitution
- Engineering → PPE → Substitution → Administrative → Elimination
Correct answer: Elimination → Substitution → Engineering → Administrative → PPE
The hierarchy places elimination first as most effective, followed by substitution, engineering controls, administrative controls, and PPE as the last resort.
Question 7: A worker enters a confined space and immediately collapses. Other workers rush in to help but also collapse. What is the most likely hazard?
- Carbon monoxide from a gas engine nearby
- Oxygen-deficient atmosphere (Correct answer)
- High concentration of toxic gas displacing oxygen
- Hydrogen sulfide from decomposing organic matter
Correct answer: Oxygen-deficient atmosphere
An oxygen-deficient atmosphere (below 19.5% O₂) causes rapid incapacitation, and rescuers who enter without supplied air become victims themselves.
STSC Health Hazards and Hygiene 5
Under the OSHA Hazard Communication Standard, what must a Safety Data Sheet (SDS) Section 8 specifically contain?