ASP Industrial Hygiene and Health 5 — Questions and Answers
Question 1: Which skin absorption route is most significant for lipophilic (fat-soluble) chemicals in an occupational setting?
- Percutaneous absorption through intact skin (Correct answer)
- Absorption through mucous membranes
- Absorption through open wounds only
- Ingestion of skin-deposited material
Correct answer: Percutaneous absorption through intact skin
Lipophilic chemicals readily penetrate the lipid-rich stratum corneum of intact skin, making percutaneous absorption the primary dermal route.
Question 2: The noise dose for a worker is calculated as 100%. According to OSHA 29 CFR 1910.95, this worker is at the action level requiring which control?
- Mandatory hearing protection and audiometric testing (Correct answer)
- Engineering controls must be immediately implemented
- Administrative controls only
- No action required as the dose equals but does not exceed the PEL
Correct answer: Mandatory hearing protection and audiometric testing
A dose of 100% equals the OSHA PEL (TWA of 90 dBA), triggering mandatory audiometric testing, training, and hearing protector provision.
Question 3: Which air-purifying respirator cartridge color code designates organic vapor protection in the US?
- Yellow
- Black (Correct answer)
- Green
- White
Correct answer: Black
NIOSH color coding assigns black cartridges to organic vapor protection under 42 CFR Part 84.
Question 4: A wipe sample collected from a worker's hand shows lead contamination. This finding is most directly indicative of which exposure pathway?
- Inhalation
- Ingestion via hand-to-mouth contact (Correct answer)
- Dermal absorption
- Injection
Correct answer: Ingestion via hand-to-mouth contact
Lead on the hands poses a significant ingestion risk through hand-to-mouth contact, particularly during eating, drinking, or smoking.
Question 5: Which industrial hygiene control is considered most preferred in the hierarchy of controls?
- Administrative controls
- PPE
- Substitution (Correct answer)
- Engineering controls
Correct answer: Substitution
Substitution (replacing a hazardous material or process with a safer one) is ranked above engineering controls and is second only to elimination in the hierarchy.
Question 6: A chemical with a short biological half-life is best monitored using which biological monitoring timing strategy?
- Pre-shift sample on Monday
- End-of-shift sample (Correct answer)
- 48 hours post-exposure
- Weekly random sampling
Correct answer: End-of-shift sample
Chemicals with short biological half-lives are quickly metabolized or excreted, so end-of-shift sampling captures peak biomarker concentrations.
Question 7: Under OSHA's Hazard Communication Standard (HazCom 2012/GHS), which section of a Safety Data Sheet (SDS) lists occupational exposure limits?
- Section 2 – Hazard Identification
- Section 8 – Exposure Controls/Personal Protection (Correct answer)
- Section 11 – Toxicological Information
- Section 15 – Regulatory Information
Correct answer: Section 8 – Exposure Controls/Personal Protection
Section 8 of the GHS-aligned SDS contains PELs, TLVs, engineering controls, and recommended PPE for occupational use.
ASP Industrial Hygiene and Health 5
Which skin absorption route is most significant for lipophilic (fat-soluble) chemicals in an occupational setting?