Section 192.59 - Plastic pipe(a) New plastic pipe is qualified for use under this part if: (1) It is manufactured in accordance with a listed specification;(2) It is resistant to chemicals with which contact may be anticipated; and(3) It is free of visible defects.(b) Used plastic pipe is qualified for use under this part if:(1) It was manufactured in accordance with a listed specification;(2) It is resistant to chemicals with which contact may be anticipated;(3) It has been used only in gas service; (4) Its dimensions are still within the tolerances of the specification to which it was manufactured; and(5) It is free of visible defects.(c) For the purpose of paragraphs (a)(1) and (b)(1) of this section, where pipe of a diameter included in a listed specification is impractical to use, pipe of a diameter between the sizes included in a listed specification may be used if it: (1) Meets the strength and design criteria required of pipe included in that listed specification; and(2) Is manufactured from plastic compounds which meet the criteria for material required of pipe included in that listed specification.35 FR 13257, 8/19/1970, as amended by Amdt. 192-19, 40 FR 10472, 3/6/1975; Amdt. 192-58, 53 FR 1635, 1/21/1988; 83 FR 58716, 1/22/2019