(a) A containment system carrying liquid sulfur must have:
(1) A cargo tank ventilation system that:
- (i) Maintains the H2S vapor concentration below 1.85 percent by volume; and
- (ii) Prevents sulfur buildup within itself; and
- (2) An alarm system designed to operate when the ventilation system blower fails.
- (b) The void spaces around a cargo tank that carries liquid sulfur must be oil tight.
- (c) A cargo tank that carries liquid sulfur and the void spaces surrounding the tank must have connections for sampling vapor.