46 CFR 35.30-40 - Flammable liquid and gas fuels as ship's stores - TB/ALL.
Flammable liquids and gases other than diesel fuel, to be used as fuel for approved equipment must satisfy the following:
(b) The contents must be marked on the containers, and the containers must be labeled in accordance with DOT requirements for flammable liquids and gases.
(c) Containers must be stowed on or above the weather deck in locations designated by the master. Containers specified in paragraph (a)(1) of this section which do not exceed a capacity of five gallons may be stowed below the weather deck in a paint or lamp locker.