49 CFR §192.503

1. (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. (1)It has been tested in accordance with this subpart and § 192.619 to substantiate the maximum allowable operating pressure; and
   2. (2)Each potentially hazardous leak has been located and eliminated.
2. (b)The test medium must be liquid, air, natural gas, or inert gas that is—
   1. (1)Compatible with the material of which the pipeline is constructed;
   2. (2)Relatively free of sedimentary materials; and
   3. (3)Except for natural gas, nonflammable.
3. (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:
4. (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.
5. (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. (1)The component was tested to at least the pressure required for the pipeline to which it is being added;
   2. (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. (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.