Section 192.503 - General requirements(a) No person may operate a new segment of pipeline, or return to service a segment of pipeline that has been relocated or replaced, until- (1) It has been tested in accordance with this subpart and §192.619 to substantiate the maximum allowable operating pressure; and(2) Each potentially hazardous leak has been located and eliminated.(b) The test medium must be liquid, air, natural gas, or inert gas that is-(1) Compatible with the material of which the pipeline is constructed;(2) Relatively free of sedimentary materials; and(3) Except for natural gas, nonflammable.(c) Except as provided in §192.505(a), if air, natural gas, or inert gas is used as the test medium, the following maximum hoop stress limitations apply: | Class location | Maximum hoop stress allowed as percentage of SMYS |
| Natural gas | Air or inert gas |
| 1 | 80 | 80 |
| 2 | 30 | 75 |
| 3 | 30 | 50 |
| 4 | 30 | 40 |
(d) Each joint used to tie in a test segment of pipeline is excepted from the specific test requirements of this subpart, but each non-welded joint must be leak tested at not less than its operating pressure.(e) If a component other than pipe is the only item being replaced or added to a pipeline, a strength test after installation is not required, if the manufacturer of the component certifies that:(1) The component was tested to at least the pressure required for the pipeline to which it is being added;(2) The component was manufactured under a quality control system that ensures that each item manufactured is at least equal in strength to a prototype and that the prototype was tested to at least the pressure required for the pipeline to which it is being added; or(3) The component carries a pressure rating established through applicable ASME/ANSI, Manufacturers Standardization Society of the Valve and Fittings Industry, Inc. (MSS) specifications, or by unit strength calculations as described in §192.143.35 FR 13257, 8/19/1970, as amended by Amdt. 192-58, 53 FR 1635, 1/21/1988; Amdt. 192-60, 53 FR 36029, 9/16/1988; Amdt. 192-60A, 54 FR 5485, 2/3/1989; Amdt. 192-120, 80 FR 12779, 3/11/2015