46 CFR § 153.280
Piping system design
April 15, 2021
(a) Each cargo piping system must meet the standards of Part 56 and §§38.10-1(b), 38.10-1(e), and 38.10-10(a) of this chapter.
(b) Piping carrying cargo or cargo residue may not enter any machinery space except a cargo pumproom.