Tankerman · Cargo Properties — Flammable Range
A hydrocarbon vapor/air mixture will NOT burn when it is:
- AExactly at the lower explosive limit
- BAbove the upper explosive limit (too rich)✓ Correct
- CIn the middle of the flammable range
- DAt the stoichiometric point
Explanation
Combustion requires a mixture between the lower and upper explosive limits (LEL/UEL). Above the UEL the mixture is too rich (too little oxygen) to ignite; below the LEL it is too lean. An inerted tank stays below the LEL by lack of oxygen.
Authority: ISGOTT; Bowditch
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