CMSP CMSP Occupational Health & Industrial Hygiene 1 — Questions and Answers
Question 1: What is the MSHA permissible exposure limit (PEL) for respirable coal mine dust for miners without pneumoconiosis?
- 1.0 mg/m³
- 2.0 mg/m³ (Correct answer)
- 0.5 mg/m³
- 5.0 mg/m³
Correct answer: 2.0 mg/m³
MSHA's PEL for respirable coal mine dust is 2.0 mg/m³ for miners who do not have evidence of pneumoconiosis.
Question 2: Coal workers' pneumoconiosis (CWP), commonly called 'black lung,' is caused by prolonged inhalation of:
- Silica dust only
- Respirable coal and mixed mine dust (Correct answer)
- Nitrogen dioxide fumes
- Diesel particulate matter
Correct answer: Respirable coal and mixed mine dust
CWP results from the long-term deposition of respirable coal and mixed mine dust in the lungs, causing progressive fibrosis.
Question 3: Which industrial hygiene sampling method is required by MSHA to assess a miner's personal exposure to respirable dust?
- Area sampling with fixed monitors
- Personal breathing zone sampling using a personal dust monitor (PDM) (Correct answer)
- Bulk dust sampling at the conveyor
- Wipe sampling on surfaces
Correct answer: Personal breathing zone sampling using a personal dust monitor (PDM)
MSHA requires personal breathing zone sampling to capture the actual dust concentration inhaled by individual miners during their work shift.
Question 4: What does the term 'threshold limit value – time weighted average' (TLV-TWA) represent?
- The maximum instantaneous exposure allowed
- The average airborne concentration to which workers may be exposed 8 hours/day, 40 hours/week without adverse effects (Correct answer)
- The short-term exposure limit for a 15-minute period
- The immediately dangerous to life or health (IDLH) concentration
Correct answer: The average airborne concentration to which workers may be exposed 8 hours/day, 40 hours/week without adverse effects
The TLV-TWA is the ACGIH-established concentration for a normal 8-hour workday and 40-hour workweek that nearly all workers can be repeatedly exposed to without adverse health effects.
Question 5: Which of the following best describes the 'hierarchy of controls' approach to occupational health hazards in mining?
- PPE → engineering controls → administrative controls → elimination
- Elimination → substitution → engineering controls → administrative controls → PPE (Correct answer)
- Administrative controls → PPE → engineering controls → elimination
- Engineering controls → substitution → elimination → PPE
Correct answer: Elimination → substitution → engineering controls → administrative controls → PPE
The hierarchy of controls prioritizes elimination of the hazard first, then substitution, engineering controls, administrative controls, and PPE as the last resort.
Question 6: What health condition is associated with prolonged occupational exposure to crystalline silica dust in mining?
- Asbestosis
- Silicosis (Correct answer)
- Mesothelioma
- Byssinosis
Correct answer: Silicosis
Silicosis is an irreversible and potentially fatal lung disease caused by inhaling crystalline silica dust, common in hard rock and certain coal mining operations.
