Tankerman · Inert Gas — Oxygen Limit
Under SOLAS, inert gas supplied to cargo tanks must have an oxygen content not exceeding:
- A2% by volume
- B5% by volume
- C8% by volume✓ Correct
- D21% by volume
Explanation
The inert gas delivered must contain not more than 8% oxygen by volume, and tank atmospheres are kept below about 8% (often maintained near 5%) at positive pressure to stay below the flammable range.
Authority: SOLAS Chapter II-2 (inert gas systems)
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