Code of Federal Regulations Title 46. Shipping § 46.154.903 Inert gas systems:  General

(a) Inert gas carried or generated to meet §§ 154.901, 154.902, and 154.1848 must be non-flammable and non-reactive with the cargoes that the vessel is certificated to carry and the materials of construction of the cargo tanks, hold and interbarrier spaces, and insulation.

(b) The boiling point and dew point at atmospheric pressure of the inert gas must be below the temperature of any surface in those spaces or –45° C (–49° F), whichever is warmer.

(c) For the temperatures and pressures at which the gas is stored and used, storage vessels and inert gas piping must meet §§ 154.450 and 154.500 respectively.