Section 6-77-38 - Design limitations for plastic pipe(a) The design pressure may not exceed a gauge pressure of 689 kPa (100 p.s.i.g.) for plastic pipe used in: (1) Distribution systems; or(2) Class 3 and 4 locations.(b) Plastic pipe may not be used where operating temperatures of the pipe will be: (1) Below minus 29E C (-20E F); or(2) In the case of thermoplastic pipe, above the temperature at which the long-term hydrostatic strength used in the design formula under §6 77-34 is determined, except that pipe manufactured before May 18, 1978, may be used at temperatures up to 38E C (100E F); or in the case of reinforced thermosetting plastic pipe, above 66E C (150E F).(c) The wall thickness for thermoplastic pipe may not be less than 1.57 millimeters (0.062 in.).(d) The wall thickness for reinforced thermosetting plastic pipe may not be less than that listed in the following table: | Nominal size in inches | Minimum wall thickness in millimeters (inches) |
| 2....................................... | | 1.52(0.060) |
| 3.......................................| | 1.52(0.060) |
| 4....................................... | | 1.78(0.070) |
| 6....................................... | | 2.54(0.100) I |
[Eff ] (Auth: HRS § 269-6) (Imp: 49 C.F.R. §192.123, OCT 1, 1990)