Tankerman · Gas Carrier — Rollover
The 'rollover' hazard on an LNG carrier or storage tank is:
- ACargo solidifying into ice
- BThe ship physically capsizing
- CA sudden mixing of stratified layers of different density that releases a large volume of vapor at once✓ Correct
- DA loss of all cargo lighting
Explanation
If LNG forms stratified layers of differing density/composition, the layers can abruptly overturn (roll over) and rapidly release a large quantity of vapor, over-pressurizing the tank. It is prevented by avoiding stratification (proper loading, recirculation, and monitoring density/temperature).
Authority: IGC Code; LNG operations references
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