Tankerman · Cargo Grades
Under U.S. tank vessel regulations, a 'Grade A' flammable liquid is one with the:
- ALowest flash point / highest vapor pressure (most volatile)✓ Correct
- BHighest flash point
- CHighest viscosity
- DLowest API gravity
Explanation
Grades A through D are flammable liquids ranked by vapor pressure and flash point, with Grade A the most volatile (highest Reid vapor pressure). Grade E is combustible (higher flash point). Volatility drives the precautions.
Authority: 46 CFR 30.10 (grades of liquid cargo)
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