ASP Industrial Hygiene and Health 4 — Questions and Answers
Question 1: Which sampling method is most appropriate when a worker's exposure to an air contaminant varies significantly throughout the shift?
- Grab sampling
- Full-period consecutive samples (Correct answer)
- Instantaneous sampling
- Grab sample averaged over 15 minutes
Correct answer: Full-period consecutive samples
Full-period consecutive samples capture the entire shift exposure, providing the most accurate TWA when concentration varies.
Question 2: The ACGIH Biological Exposure Index (BEI) is intended to be used in conjunction with which other guideline?
- OSHA PELs
- NIOSH RELs
- ACGIH TLVs (Correct answer)
- EPA RfC values
Correct answer: ACGIH TLVs
BEIs are companion values to ACGIH TLVs, both serving as health-based occupational exposure guidelines.
Question 3: A worker is exposed to two chemicals, Chemical A at 50% of its TLV and Chemical B at 60% of its TLV. Assuming additive effects, what is the combined exposure ratio?
- 0.55
- 0.60
- 1.00
- 1.10 (Correct answer)
Correct answer: 1.10
For additive effects, sum the individual exposure ratios: 0.50 + 0.60 = 1.10, which exceeds 1.0 and indicates overexposure.
Question 4: Which ionizing radiation type has the greatest penetrating power?
- Alpha particles
- Beta particles
- Gamma rays (Correct answer)
- Neutrons
Correct answer: Gamma rays
Gamma rays are high-energy photons that can penetrate several centimeters of lead, far exceeding alpha or beta particles.
Question 5: In industrial hygiene, the term 'IDLH' stands for which concept?
- Immediately Dangerous to Life or Health (Correct answer)
- Integrated Daily Limit for Hazards
- Industrial Default Limit for Hydrocarbons
- Interim Daily Level for Health
Correct answer: Immediately Dangerous to Life or Health
IDLH represents the concentration at which a worker cannot escape without a respirator or would suffer irreversible health effects within 30 minutes.
Question 6: Which type of ventilation control is best suited for controlling emissions from a low-toxicity, large-area diffuse source?
- Local exhaust ventilation (LEV)
- General dilution ventilation (Correct answer)
- Recirculation ventilation
- Push-pull ventilation
Correct answer: General dilution ventilation
General dilution ventilation dilutes contaminants with clean air across a large area and is cost-effective for low-toxicity diffuse sources.
Question 7: Which OSHA respiratory protection standard requires a written program when respirators are required?
- 29 CFR 1910.134 (Correct answer)
- 29 CFR 1910.132
- 29 CFR 1910.146
- 29 CFR 1910.119
Correct answer: 29 CFR 1910.134
29 CFR 1910.134 mandates a written respiratory protection program including medical evaluation, fit testing, and training.
ASP Industrial Hygiene and Health 4
Which sampling method is most appropriate when a worker's exposure to an air contaminant varies significantly throughout the shift?