46 CFR § 197.336
Pressure piping
April 15, 2021
Piping systems that are not an integral part of the vessel or facility, carrying fluids under pressures exceeding 15 psig must—
(a) Meet the ANSI Code;
(b) Have the point of connection to the integral piping system of the vessel or facility clearly marked; and
(c) Be tested after every repair, modification, or alteration to the pressure boundaries as set forth in §197.462.