You are on a tankship designed to carry molten sulphur. Which statement is TRUE?

A
There must be two portable toxic vapor detectors on board.
B
The cargo tank ventilation system must maintain the H2S vapor concentration at 1.85% or more by volume.
C
Cargo temperature may be taken by portable thermometers.
D
The pressure in the heating coils in the tanks must be less than that of the cargo exerted on them.
E