Tankerman · Inert Gas — Maintaining Pressure
Inerted cargo tanks are normally kept at a slight POSITIVE pressure in order to:
- ASpeed up loading
- BPrevent air (oxygen) from being drawn into the tanks✓ Correct
- CReduce cargo temperature
- DIncrease vapor pressure
Explanation
Holding positive pressure ensures any leakage is outward (inert gas escaping) rather than air being drawn in, which would raise oxygen and risk a flammable mixture. The IG plant tops up pressure as cargo is discharged or temperature falls.
Authority: SOLAS II-2; ISGOTT
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