46 CFR § 153.484 - Prewash equipment.
Unless the ship operator shows that the prewash equipment specified in this section will be available at discharge or prewash facilities or the equipment is waived under § 153.491, to have its Certificate of Inspection or Certificate of Compliance endorsed to carry a Category A NLS or a Category B or C NLS requiring viscosity or melting point information under § 153.908 (a) and (b), a ship must have the following:
(a) For the tanks that carry the NLS, a tank washing system capable of washing all interior tank surfaces except those shielded from the washing system spray by ship's structure, and consisting of a wash water supply system and -
(1) A fixed tank washing machine in each tank; or
(2) A portable tank washing machine and, if required by the Coast Guard, equipment to move it during washing and when storing.
(b) Piping, valving, and crossovers needed to arrange the cargo piping so that the wash water passes through the cargo pump and cargo piping during tank washing or discharge of tank wash water.
(c) If the approved Procedures and Arrangements Manual specifies the hot water prewash required under 153.1108, a means of supplying water to the tank washing machine under paragraph (a) of this section at -
(1) A temperature of at least 60 °C (140 °F) when it leaves the washing machine; and
(2) The flow rate needed for the washing machine jets to meet paragraph (a) of this section.