46 CFR § 153.525 - Special requirements for unusually toxic cargoes.
When Table 1 refers to this section a containment system must meet the following:
(a) Cargo piping and venting systems must be designed so that they can be separated from any containment system endorsed for a cargo not covered by this section.
(c) All cargo pumps and valves located below the weatherdeck must be operable from the weatherdeck.
(d) A heat transfer system for the cargo must:
(1) Be independent of other ship service systems, except for other cargo heat transfer systems, and not enter the engine room;
(2) Be totally external to the cargo containment system; or
(e) The cargo must be separated from any bunkers by at least two bulkheads.
(f) A cargo containment system must have a vapor return connection.