46 CFR §148.135

1. (a)Class 4.3 materials listed in Table 148.10 of this part which, in contact with water, emit flammable gases, must—
   1. (1)Be kept as cool and dry as practical before loading;
   2. (2)Not be loaded or transferred between vessels during periods of rain or snow;
   3. (3)Be stowed separate from foodstuffs and all Class 8 liquids; and
   4. (4)Be stowed in a mechanically ventilated hold. Exhaust gases must not penetrate into accommodation, work or control spaces. Unmanned barges that have adequate natural ventilation need not have mechanical ventilation.
2. (b)The bulkhead between a hold containing a Class 4.3 material and incompatible materials must have cable and conduit penetrations sealed against the passage of gas and vapor.