(a) The manufacturer must notify the Officer in Charge, Marine Inspection, of the intended fabrication of pressure vessels that will require Coast Guard inspection.

(b) For exemption of certain pressure vessels from shop inspection see § 54.01-15 of this subchapter.

(c) For a classification delineation of boilers and pressure vessels refer to tables 1 and 2 to § 54.01-5 of this subchapter.

(a) Classes I, I-L and II-L pressure vessels must be subject to shop inspection at the plant where they are being fabricated, or when determined necessary by the Officer in Charge, Marine Inspection.

(b) The manufacturer must submit Class I, I-L and II-L pressure vessels, as defined in parts 54 and 56 of this subchapter for shop inspection at such stages of fabrication as may be requested by the Officer in Charge, Marine Inspection.

(a) Class II pressure vessels must be subject to shop inspections at the plant where they are being fabricated, as or when determined necessary by the Officer in Charge, Marine Inspection. The inspections described in this section are required, unless specifically exempted by other regulations in this subchapter.

(b) The first inspection of Class II welded pressure vessels must be performed during the welding of the longitudinal joint. At this time the marine inspector must check the material and fit-up of the work, and ascertain that only welders who have passed the required tests are employed.

(c) A second inspection of Class II welded pressure vessels must be made during the welding of the circumferential joints. At this time the marine inspector must check any new material being used which may not have been examined at the time of the first inspection, also the fit-up of the vessel at this stage of fabrication, and in addition, observe the welding and ascertain that only welders who have passed the required tests are employed.

(a) Class III pressure vessels must be subject to shop inspection at the plant where they are being fabricated, as or when determined necessary by the Officer in Charge, Marine Inspection. The inspection described in this section is required, unless specifically exempted by other regulations in this subchapter.

(b) For Class III welded pressure vessels, one inspection must be made during the welding of the longitudinal joint. If there is no longitudinal joint, the inspection must be made during the welding of a circumferential joint. At this time the marine inspector must check the material and fit-up of the work and see that only welders who have passed the required tests are employed.