153.545—Special requirements for liquid sulfur.
(a)
A containment system carrying liquid sulfur must have:
(1)
A cargo tank ventilation system that:
(i)
Maintains the H2 S 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.