CSS Industrial Hygiene and Health Hazards 1 — Questions and Answers
Question 1: What is the OSHA Permissible Exposure Limit (PEL) for an 8-hour time-weighted average (TWA) for noise in general industry?
- 85 dBA
- 90 dBA (Correct answer)
- 95 dBA
- 100 dBA
Correct answer: 90 dBA
OSHA's PEL for occupational noise exposure is 90 dBA as an 8-hour TWA for general industry under 29 CFR 1910.95.
Question 2: Which sampling method measures a worker's actual breathing zone exposure to airborne contaminants throughout a work shift?
- Area sampling
- Grab sampling
- Personal sampling (Correct answer)
- Bulk sampling
Correct answer: Personal sampling
Personal sampling involves placing a collection device in the worker's breathing zone to accurately measure individual exposure over a shift.
Question 3: What term describes the concentration of a chemical at which 50% of a test animal population dies within a specified period?
- TLV
- LD50
- LC50 (Correct answer)
- IDLH
Correct answer: LC50
LC50 (Lethal Concentration 50) is the airborne concentration that kills 50% of test animals, while LD50 refers to a lethal dose via ingestion or skin contact.
Question 4: OSHA's Hazard Communication Standard (HazCom) requires Safety Data Sheets to follow which format?
- 7-section ANSI format
- 16-section GHS format (Correct answer)
- 12-section ISO format
- 10-section NFPA format
Correct answer: 16-section GHS format
OSHA's HazCom 2012 (29 CFR 1910.1200) aligns with GHS and requires SDSs to have a standardized 16-section format.
Question 5: Which type of health hazard results from a single short-term exposure to a high concentration of a substance?
- Chronic health effect
- Cumulative effect
- Acute health effect (Correct answer)
- Synergistic effect
Correct answer: Acute health effect
Acute health effects occur rapidly after a single or short-term exposure to a hazardous substance at high concentrations.
Question 6: Which industrial hygiene control is considered the most effective method for reducing worker exposure to chemical hazards?
- Administrative controls
- Personal protective equipment
- Engineering controls — elimination or substitution (Correct answer)
- Warning signs and labels
Correct answer: Engineering controls — elimination or substitution
The hierarchy of controls places elimination and substitution at the top as the most effective methods for permanently removing or reducing hazards.
CSS Industrial Hygiene and Health Hazards 1
What is the OSHA Permissible Exposure Limit (PEL) for an 8-hour time-weighted average (TWA) for noise in general industry?