CSS CSS - Certified Safety Supervisor Ergonomics and Confined Space Safety Questions and Answers 1 — Questions and Answers
Question 1: Under OSHA 29 CFR 1910.146, what defines a 'permit-required confined space'?
- Any space smaller than 4 ft × 4 ft
- A space that contains or has potential for a hazardous atmosphere, engulfment, or other recognized serious safety hazard (Correct answer)
- Any enclosed space requiring a ladder to enter
- A space with limited lighting only
Correct answer: A space that contains or has potential for a hazardous atmosphere, engulfment, or other recognized serious safety hazard
A permit-required confined space has limited entry/exit and contains or could contain a serious health or safety hazard such as a hazardous atmosphere or engulfment potential.
Question 2: What is the minimum oxygen concentration considered acceptable in a confined space atmosphere per OSHA standards?
- 16.5%
- 19.5% (Correct answer)
- 21%
- 23.5%
Correct answer: 19.5%
OSHA defines oxygen-deficient atmospheres as those with less than 19.5% oxygen; concentrations below this level require supplied-air respirators.
Question 3: Which ergonomic risk factor is most associated with cumulative trauma disorders (CTDs) of the upper extremities?
- Static posture only
- High repetition combined with forceful exertions (Correct answer)
- Cold temperatures alone
- Vibration only
Correct answer: High repetition combined with forceful exertions
Cumulative trauma disorders are most strongly associated with the combination of high repetition and forceful exertions acting on tendons, muscles, and joints.
Question 4: The Waters equation (NIOSH Lifting Equation) calculates which value to guide safe manual lifting?
- Maximum allowable weight per shift
- Recommended Weight Limit (RWL) (Correct answer)
- Cumulative trauma threshold
- Fatigue allowance index
Correct answer: Recommended Weight Limit (RWL)
The NIOSH Lifting Equation outputs a Recommended Weight Limit (RWL) that, when compared to the actual load, produces the Lifting Index.
Question 5: What is the role of an 'attendant' in a confined space entry operation under 29 CFR 1910.146?
- To enter the space and monitor air quality from inside
- To remain outside, track authorized entrants, and initiate rescue if needed (Correct answer)
- To sign the permit and authorize entry
- To operate the ventilation equipment inside the space
Correct answer: To remain outside, track authorized entrants, and initiate rescue if needed
The attendant remains outside the permit space, maintains communication with entrants, monitors for hazards, and initiates rescue procedures without entering.
Question 6: Which condition would trigger non-entry rescue rather than entry rescue for a confined space?
- Entrant slips on a wet surface inside
- Entrant becomes incapacitated in an IDLH atmosphere without a rescue team on site (Correct answer)
- Entrant requests assistance removing equipment
- Entrant loses communication for 30 seconds
Correct answer: Entrant becomes incapacitated in an IDLH atmosphere without a rescue team on site
Non-entry rescue using retrieval systems is required when the atmosphere is IDLH and a trained entry rescue team is unavailable, to prevent rescuer casualties.
CSS CSS - Certified Safety Supervisor Ergonomics and Confined Space Safety Questions and Answers 1
Under OSHA 29 CFR 1910.146, what defines a 'permit-required confined space'?