46 C.F.R. § 151.03-43 Pressure.
Title 46 - Shipping
Terminology used in this part are: pounds per square inch gauge (p.s.i.g.) or pounds per square inch absolute (p.s.i.a.). 14.7 p.s.i.a. is equal to 0 p.s.i.g. P.s.i.g. is normally used in reference to design or operating requirements.
Title 46: Shipping
PART 151—BARGES CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES
Subpart 151.03—Definitions
§ 151.03-43 Pressure.