Questar Gas - Good Practices for Gas Piping and Appliance ...

In no case is it acceptable to repair defects in pipe or fittings.
The defective pipe, fitting or threaded joint having been located
shall be removed and replaced with sound material.
9. LP GAS: When changing from LP gas to natural gas, the supply
line from the LP gas tank must be disconnected and plugged
before natural gas will be turned into the building.
10. INSTALLATION OF GAS PIPING: All joints in an iron piping
system, unless welded, shall be threaded joints, having approved
standard threads. Threaded joints shall be made up with
approved pipe thread compound or teflon tape on male threads
only.
Gas piping downstream of the point of delivery is no longer
allowed to enter or exit a building at a point below grade. This
requirement is intended to lessen the possibility of gas leakage
entering a builidng through a foundation wall penetration.
Fuel lines extending through a foundation wall, above ground,
shall have protective coating, wrap or sleeve.
Location Limitations: Gas piping inside any building shall not
be run in or through an air duct, clothes chute, chimney or vent,
ventilating duct, dumbwaiter or elevator shaft.
Piping installed downstream of the point of delivery shall not
extend through any townhouse unit other than the unit served
by such piping. Refer to IFGC 404.1.
Gas piping may be installed in accessible above-ceiling spaces.
Changes in direction of gas pipe shall be made by the use of
fittings, factory bends or field bends. Refer to IFGC 405.2 for
field bend requirements.
All rigid gas piping shall be adequately supported by metal
straps or hooks at intervals not to exceed those listed:
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