OSHA Confined Space Entry 1 — Questions and Answers
Question 1: Under OSHA 29 CFR 1910.146, what is the definition of a permit-required confined space?
- A space large enough to enter, with limited entry/exit, and not designed for continuous occupancy, plus one or more serious hazard (Correct answer)
- Any space that requires a ladder to enter
- Any underground vault or tank
- A space that requires two or more employees to access
Correct answer: A space large enough to enter, with limited entry/exit, and not designed for continuous occupancy, plus one or more serious hazard
OSHA defines a permit-required confined space as a space meeting all three size/entry criteria AND containing at least one serious hazard such as a hazardous atmosphere, engulfment risk, or converging walls.
Question 2: Who is responsible for signing and authorizing an entry permit for a permit-required confined space?
- The entry supervisor (Correct answer)
- The attendant
- The authorized entrant
- The safety officer
Correct answer: The entry supervisor
The entry supervisor is responsible for signing the entry permit, verifying all conditions are acceptable, and authorizing entry into a permit-required confined space.
Question 3: What is the primary duty of an attendant during confined space entry operations?
- Remain outside the space and monitor entrants and conditions continuously (Correct answer)
- Enter the space to assist the entrant if needed
- Test the atmosphere inside the space every 30 minutes
- Maintain the ventilation equipment inside the space
Correct answer: Remain outside the space and monitor entrants and conditions continuously
The attendant must remain outside the permit space, keep count of entrants, monitor conditions, and initiate rescue if necessary — they must never enter the space themselves.
Question 4: What atmospheric oxygen level is considered immediately dangerous to life or health (IDLH) in a confined space?
- Below 16% or above 25%
- Below 19.5% or above 23.5% (Correct answer)
- Below 18% or above 22%
- Below 15% or above 20%
Correct answer: Below 19.5% or above 23.5%
OSHA specifies that an atmosphere with less than 19.5% or more than 23.5% oxygen is considered hazardous and requires respiratory protection or ventilation.
Question 5: Before an employee enters a permit-required confined space, what must be tested first?
- Temperature
- Atmospheric conditions (oxygen, flammable gases, toxic substances) (Correct answer)
- Lighting levels
- Noise levels
Correct answer: Atmospheric conditions (oxygen, flammable gases, toxic substances)
OSHA requires that atmospheric conditions be tested for oxygen content, flammable gases/vapors, and potential toxic air contaminants before any entry occurs.
Question 6: Which of the following is a non-entry rescue method acceptable under OSHA's confined space standard?
- Sending in a second employee with a respirator
- Using a retrieval system with a lifeline attached to the entrant's body harness (Correct answer)
- Calling 911 and waiting for fire department rescue
- Lowering a stretcher into the space
Correct answer: Using a retrieval system with a lifeline attached to the entrant's body harness
OSHA requires employers to provide retrieval systems (lifelines and harnesses) so that entrants can be rescued without another person entering the space, which is the preferred non-entry rescue method.
OSHA Confined Space Entry 1
Under OSHA 29 CFR 1910.146, what is the definition of a permit-required confined space?