CSP Certified Safety Professional (CSP) Comprehensive 3 — Questions and Answers
Question 1: What does the term 'IDLH' stand for in industrial hygiene and what is its primary purpose?
- Immediately Dangerous to Life or Health; defines concentrations requiring SCBA or equivalent (Correct answer)
- Integrated Daily Limit for Hazards; sets 8-hour TWA exposure limits
- Industrial Default Level for Hygiene; establishes engineering control thresholds
- Incremental Dose Limit for Hazardous substances; guides medical surveillance
Correct answer: Immediately Dangerous to Life or Health; defines concentrations requiring SCBA or equivalent
IDLH (Immediately Dangerous to Life or Health) represents the maximum concentration from which a worker could escape within 30 minutes without irreversible health effects, and requires supplied-air respirators.
Question 2: Under NFPA 70E, electrical work requiring an energized electrical work permit typically involves circuits operating above what voltage threshold when exposed energized conductors are within the restricted approach boundary?
- 50 volts (Correct answer)
- 120 volts
- 208 volts
- 480 volts
Correct answer: 50 volts
NFPA 70E applies shock protection requirements beginning at 50 volts and above, where the risk of electric shock and arc flash becomes significant.
Question 3: Which of the following best describes the 'Swiss Cheese Model' of accident causation?
- Accidents result from a single catastrophic human error that overwhelms all defenses
- Accidents occur when holes in multiple defensive layers align, allowing a hazard to cause harm (Correct answer)
- Accidents are caused exclusively by equipment failures rather than human factors
- Accidents follow a linear domino sequence starting with an unsafe act
Correct answer: Accidents occur when holes in multiple defensive layers align, allowing a hazard to cause harm
James Reason's Swiss Cheese Model depicts safety defenses as slices with holes; accidents occur when holes in multiple layers align to create an unobstructed path to harm.
Question 4: A worker is exposed to three chemicals simultaneously: Chemical A at 50% of its PEL, Chemical B at 30% of its PEL, and Chemical C at 40% of its PEL. Using the additive mixture formula, is the combined exposure acceptable?
- Yes, because no individual chemical exceeds its PEL
- No, because the sum of fractions (1.2) exceeds 1.0 (Correct answer)
- Yes, because the geometric mean is below 0.5
- No, because any fraction above 0.25 triggers automatic overexposure
Correct answer: No, because the sum of fractions (1.2) exceeds 1.0
For additive mixtures, the sum of fractions (0.50 + 0.30 + 0.40 = 1.20) must not exceed 1.0; this exposure exceeds the combined limit.
Question 5: Under OSHA 29 CFR 1910.147 (Lockout/Tagout), which employees must receive training when LOTO procedures are implemented?
- Only authorized employees who perform lockout
- Only affected employees who operate equipment
- Both authorized employees and affected employees (Correct answer)
- All employees on the worksite regardless of role
Correct answer: Both authorized employees and affected employees
OSHA 1910.147 requires training for both authorized employees (who apply LOTO devices) and affected employees (who operate or work in areas where LOTO is used).
Question 6: In ergonomics, which factor is NOT one of the primary risk factors for work-related musculoskeletal disorders (WMSDs) as identified by OSHA?
- Repetition
- Awkward postures
- Worker age (Correct answer)
- Contact stress
Correct answer: Worker age
OSHA identifies repetition, awkward postures, forceful exertions, vibration, and contact stress as primary WMSD risk factors; worker age is a personal characteristic, not a primary occupational risk factor.
Question 7: Which fire class designation applies to fires involving energized electrical equipment?
- Class A
- Class B
- Class C (Correct answer)
- Class D
Correct answer: Class C
Class C fires involve energized electrical equipment and require non-conductive extinguishing agents such as CO2 or dry chemical.
CSP Certified Safety Professional (CSP) Comprehensive 3
What does the term 'IDLH' stand for in industrial hygiene and what is its primary purpose?