During a confined space entry operation, the atmospheric testing reveals 19% oxygen content. What action should be taken?
Correct Answer
B) Ventilate the space and retest before entry
OSHA requires oxygen levels between 19.5% and 23.5% for safe confined space entry. At 19% oxygen, the space must be ventilated and retested to bring oxygen levels within the acceptable range before entry can proceed.
Why This Is the Correct Answer
OSHA 29 CFR 1926.95 requires oxygen levels between 19.5% and 23.5% for safe confined space entry. At 19% oxygen, the space is oxygen-deficient by 0.5%, which creates a hazardous atmosphere. Ventilation is the appropriate corrective action to increase oxygen levels back to the acceptable range. Once ventilated and retested to confirm oxygen levels are at or above 19.5%, entry can safely proceed.
Why the Other Options Are Wrong
Option A: Enter with supplied-air respiratory protection only
Canceling the operation is unnecessarily extreme when the oxygen deficiency is minor (only 0.5% below minimum) and can be easily corrected through proper ventilation procedures.
Option D: Proceed with entry using standard PPE
Standard PPE does not address the oxygen deficiency issue. Entry with inadequate oxygen levels can cause dizziness, impaired judgment, and potentially unconsciousness, making this option unsafe.
Memory Technique
Remember '19.5 to 23.5 to stay alive' - if oxygen is outside this range, fix the atmosphere before entry, don't just mask the problem with PPE.
Reference Hint
OSHA 29 CFR 1926.95 - Personal Protective Equipment, and confined space entry standards in safety reference materials
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