Wisconsin Administrative Code
Public Service Commission
Chapter PSC 135 - Gas Safety
Subchapter II - Additions to 49 CFR Part 192
Section PSC 135.321 - Installation of plastic pipe additions [49 CFR 192.321]

(fw) The casing pipe shall be reamed and cleaned to the extent necessary to remove any sharp edges, projections, or abrasive material which could damage the plastic during and after insertion. That portion of the plastic piping which spans disturbed earth shall be adequately protected by a bridging piece or other means from crushing or shearing from external loading or settling of backfill. Care shall be taken to prevent the plastic piping from bearing on the end of the casing.

(jw) Care shall be exercised to avoid rough handling of plastic pipe and tubing. It shall not be pushed or pulled over sharp projections, dropped or have other objects dropped upon it. Caution shall be taken to prevent kinking or buckling, and any kinks or buckles which occur shall be removed by cutting out as a cylinder.

(kw) Changes in direction of plastic piping may be made with bends, tees or elbows under the following limitations:

(Lw) Plastic piping shall be laid on undisturbed or well compacted soil. If plastic piping is to be laid in soils which may damage it, the piping shall be protected by suitable rock free materials before back-filling is completed. Plastic piping shall not be supported by blocking. Well tamped earth or other continuous support shall be used.