A confined space has been tested and shows 18% oxygen, no toxic gases, and no flammable vapors. Can entry proceed?
Correct Answer
B) No, oxygen level is too low
The oxygen level of 18% is below the required minimum of 19.5% for safe entry. The space must be ventilated or supplied air equipment must be used before entry.
Why This Is the Correct Answer
OSHA regulations require a minimum oxygen concentration of 19.5% for safe entry into confined spaces. At 18% oxygen, workers face the risk of oxygen deficiency, which can cause impaired judgment, increased heart rate, and potentially unconsciousness. Even though no toxic gases or flammable vapors are present, the low oxygen level alone makes entry unsafe. The space must be properly ventilated to increase oxygen levels or workers must use supplied air respiratory equipment before entry can proceed.
Why the Other Options Are Wrong
Option A: Yes, the space is safe for entry
Although continuous monitoring is a good safety practice, the immediate issue is that the oxygen level is too low for safe entry, not the lack of monitoring equipment.
Option C: Yes, but only with supplied air respirators
While supplied air respirators would protect workers from the low oxygen environment, the question asks if entry can proceed based on the current test results, and the answer is no - additional safety measures are required first.
Memory Technique
Remember '19.5 to stay alive' - oxygen levels below 19.5% are dangerous for confined space entry
Reference Hint
OSHA 29 CFR 1926.95 - Personal Protective Equipment, and confined space entry standards in safety management chapters
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