Tankerman · Operations — Crude Oil Washing
Crude oil washing (COW) of cargo tanks must be carried out only when the tank atmosphere is:
- AFull of fresh air
- BInerted (oxygen at or below the required limit)✓ Correct
- CAt ambient oxygen
- DFilled with steam
Explanation
COW uses the cargo itself as a washing medium and is permitted only in an inerted atmosphere (oxygen controlled), because the high-velocity oil jets and mist would otherwise create a serious explosion risk. Oxygen is monitored throughout.
Authority: MARPOL Annex I; SOLAS II-2; ISGOTT
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