46 C.F.R. § 154.705 Cargo boil-off as fuel: General.
Title 46 - Shipping
(a) Each cargo boil-off fuel system under §154.703(c) must meet §§154.706 through 154.709. (b) The piping in the cargo boil-off fuel system must have a connection for introducing inert gas and for gas freeing the piping in the machinery space. (c) A gas fired main propulsion boiler or combustion engine must have a fuel oil fired pilot that maintains fuel flow as required under §154.1854 if the gas fuel supply is cut-off.
Title 46: Shipping
PART 154—SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES
Subpart C—Design, Construction and Equipment
Cargo Pressure and Temperature Control
§ 154.705 Cargo boil-off as fuel: General.

