T12 PORTABLE TANK INSTRUCTION T12
The general provisions of section 4.2.1 and the requirements of section 6.7.2 shall be met.
Minimum test pressure 6 bar
Minimum shell thickness (reference steel) 5 mm for tanks up to 1.80 m diameter and for larger tanks carrying solids of packing group II or III; 6 mm otherwise.
Pressure-relief provisions A frangible disc preceding a spring-loaded pressure-relief device, or an approved relief device constructed of materials compatible with the load.
Bottom opening provisions 3 shut-off devices required.
Alternatives permitted T14, T16, T18, T19, T20, T22

Special packing provisions:

TP2
The degree of filling prescribed in 4.2.1.9.3 shall not be exceeded.
TP7
Air shall be eliminated from the vapour space by nitrogen or other means.
TP13
Self-contained breathing apparatus shall be provided when this substance is transported, unless no self-contained breathing apparatus, as required by SOLAS regulation II-2/19 (II-2/54), is on board.