New York Codes, Rules and Regulations › Title 16 - DEPARTMENT OF PUBLIC SERVICE › Chapter III - GAS UTILITIES › Subchapter C - Safety › Part 255 - Transmission And Distribution Of Gas › General Construction Requirements for Transmission Lines and Mains › Section 255.321 - Installation of plastic pipe

Current through Register Vol. 46, No. 28, July 10, 2024
(a)
					 Plastic pipe must be installed below ground level unless otherwise permitted by
					 subdivisions (l) and (m) of this section.
(b) Plastic pipe that is installed in a vault
					 or any other below grade enclosure must be completely encased in gas-tight
					 metal pipe and fittings that are adequately protected from corrosion.
(c) Plastic pipe must be installed so as to
					 minimize shear or tensile stresses.
(d) Thermoplastic pipe that is not encased
					 must have a minimum wall thickness of 0.090 inch (2.29 millimeters), except
					 that pipe with an outside diameter of 0.875 inch (22.3 millimeters) or less may
					 have a minimum wall thickness of 0.062 inch (1.58 millimeters).
(e) Plastic pipe that is not encased must
					 have an electrically conductive wire or other approved means of locating the
					 pipe. Tracer wire may not be wrapped around the pipe and contact with the pipe
					 must be minimized but is not prohibited. Tracer wire or other metallic elements
					 installed for pipe locating purposes must be resistant to corrosion damage,
					 either by use of coated copper wire or by other means.
(f) Plastic pipe that is being encased must
					 be inserted into the casing pipe in a manner that will protect the plastic. The
					 leading end of the plastic must be closed before insertion. The casing must be
					 prepared to the extent necessary to remove sharp edges, projections, or
					 abrasive material which could damage the plastic.
(g) 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.
(h) 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.
(i) Squeeze-offs
					 of plastic may be made to control flows in accordance with manufacturer's
					 recommendations and a proven procedure without replacement of the pipe section.
					 However, each squeeze-off must be adequately marked on the pipe to preclude
					 further squeeze-off at that location.
(j) The piping shall be installed with
					 sufficient slack to provide for possible contraction. Cooling may be necessary
					 before the last connection is made under extremely high temperature
					 conditions.
(k) That portion of the
					 plastic piping exposed due to the removal of a section of the casing or which
					 spans disturbed earth shall be of sufficient strength to withstand the external
					 loading and shearing forces or it shall be protected with a suitable bridging
					 piece.
(l) Uncased plastic pipe may
					 be temporarily installed above ground level under the following conditions:
(1) The operator must be able to demonstrate
					 that the cumulative above ground exposure of the pipe does not exceed the
					 manufacturer's recommended maximum period of exposure or two years, whichever
					 is less.
(2) The pipe is located
					 where damage by external forces is unlikely or is otherwise protected against
					 such damage.
(3) The pipe
					 adequately resists exposure to ultraviolet light and high and low
					 temperatures.