33 CFR § 401.80 - Reporting dangerous cargo.
(a) The master of any explosive vessel or hazardous cargo vessel shall report to a Seaway station, as set out in Schedule III, the nature, quantity, and IMO classification of the dangerous cargo and where it is stowed on the vessel.
(b) The master of any vessel, that takes on explosive or hazardous cargo while in the Seaway, shall report to the nearest Seaway station at least four hours prior to commencing transit from a port, dock or wharf, the nature, quantity and IMO classification of the dangerous cargo and where it is stowed on the vessel.
(c) Vessels carrying “Certain Dangerous Cargo” (CDC) as defined in the United States Coast Guard regulations 33 CFR 160.202, which is the same as the definition in the Transport Canada “Marine Transportation Security Regulations” (MTSR's), shall report the “Certain Dangerous Cargo” to the nearest Seaway station prior to a Seaway transit.