REPFF Exit Exam • Set 2 Question 20 of 30

A concentration of only ____ % will induce rapid unconsciousness

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Direct Answer

Option B: 10%

Carbon dioxide concentrations reaching approximately 10 percent by volume create a lethal, oxygen-deficient atmosphere that rapidly induces immediate unconsciousness, respiratory arrest, and fatality without self-contained breathing apparatus.

All Options

10% (Correct Answer)

70%

0.33%

Detailed Explanation & Context

Relevant Framework: STCW 2010 Manila Amendments • DG Shipping E-Learning & Exit Exam Standards • Refresher Fire Prevention & Fire Fighting (REPFF).

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