CMSP CMSP Occupational Health & Industrial Hygiene 2 — Questions and Answers
Question 1: Noise-induced hearing loss (NIHL) in mining is classified as what type of occupational hazard?
- Chemical hazard
- Physical hazard (Correct answer)
- Biological hazard
- Ergonomic hazard
Correct answer: Physical hazard
Noise is a physical energy hazard; NIHL results from physical damage to the hair cells of the inner ear caused by excessive sound pressure levels.
Question 2: MSHA's permissible noise exposure limit (action level) for an 8-hour time-weighted average is:
- 80 dBA
- 85 dBA (Correct answer)
- 90 dBA
- 95 dBA
Correct answer: 85 dBA
MSHA requires hearing conservation program enrollment when miners are exposed to an 8-hour TWA of 85 dBA or greater (action level).
Question 3: Which of the following engineering controls is most effective at reducing miner exposure to respirable dust at a continuous miner face?
- Increasing lighting levels
- Water sprays and scrubber ventilation systems (Correct answer)
- Providing hearing protection to miners
- Posting hazard warning signs
Correct answer: Water sprays and scrubber ventilation systems
Water sprays suppress dust at the generation source, and scrubber systems capture airborne dust in the return airstream, directly reducing miners' inhalation exposure.
Question 4: What is the primary purpose of a Mine Dust Personal Monitor (MDPM) as introduced by MSHA's 2014 dust rule?
- Monitor methane levels in real time
- Provide miners with continuous real-time readout of their respirable dust exposure (Correct answer)
- Replace the traditional gravimetric sampling cassette entirely
- Track miner location underground
Correct answer: Provide miners with continuous real-time readout of their respirable dust exposure
The MDPM gives miners and supervisors continuous, real-time feedback on dust concentrations so corrective actions can be taken immediately during the shift.
Question 5: In the context of industrial hygiene, 'engineering controls' for heat stress in deep underground mines primarily include:
- Mandatory rest breaks only
- Mechanical refrigeration and increased airflow to cool work areas (Correct answer)
- Provision of water and electrolyte drinks
- Acclimatization programs for new miners
Correct answer: Mechanical refrigeration and increased airflow to cool work areas
Mechanical refrigeration systems and ventilation engineering reduce the ambient heat load at the workplace, addressing heat stress at the source.
Question 6: Which biological monitoring approach is used to evaluate a miner's internal dose of a toxic substance rather than ambient air concentration?
- Ambient air sampling
- Biological exposure index (BEI) testing of blood or urine (Correct answer)
- Surface wipe sampling
- Noise dosimetry
Correct answer: Biological exposure index (BEI) testing of blood or urine
Biological monitoring measures metabolites or the substance itself in body fluids, reflecting the actual dose absorbed regardless of exposure route.
CMSP CMSP Occupational Health & Industrial Hygiene 2
Noise-induced hearing loss (NIHL) in mining is classified as what type of occupational hazard?