pipe. Unless otherwise authorized, cutting shall be done by an approved
type of mechanical cutter. Wheel cutters shall be used where practicable.
On steel pipe 150 mm 6 inches and larger, an approved gas cutting and
beveling machine may be used. Cutting of thermoplastic and fiberglass pipe
shall be in accordance with AGA XR0104.
3.4.1
Metallic Piping Installation
Underground piping shall be buried a minimum of 450 mm 18 inches below
grade. Changes in direction of piping shall be made with fittings only;
mitering or notching pipe to form elbows and tees or other similar type
construction will not be permitted. Branch connection may be made with
either tees or forged branch outlet fittings. Branch outlet fittings shall
be forged, flared for improvement of flow where attached to the run, and
reinforced against external strains. Aluminum alloy pipe shall not be used
in exterior locations or underground.
3.4.2
Metallic Tubing Installation
Metallic tubing shall be installed using gas tubing fittings approved by
the tubing manufacturer. Branch connections shall be made with tees. All
tubing end preparation shall be made with tools designed for the purpose.
Aluminum alloy tubing shall not be used in exterior locations or
underground.
3.4.3
Thermoplastic and Fiberglass Piping, Tubing, and Fittings
Thermoplastic and fiberglass piping, tubing, and fittings shall be
installed outside and underground only. Piping shall be buried a minimum
of 450 mm 18 inches below grade. The piping shall be installed to avoid
excessive stresses due to thermal contraction. Thermoplastic and
fiberglass piping shall only be allowed as indicated.
3.4.4
Connections Between Metallic and Plastic Piping
Connections shall be made only outside, underground, and with approved
transition fittings.
3.4.5
Piping Buried Under Buildings
Underground piping installed beneath buildings shall be run in a steel pipe
casing protected from corrosion with protective coatings as specified in
Section 02556A GAS DISTRIBUTION SYSTEM. The casing shall extend at least
100 mm 4 inches outside the building. The pipe shall have spacers and end
bushings to seal at both ends to prevent the entrance of water and escape
of gas. A vent line from the annular space shall extend above grade
outside to a point where gas will not be a hazard and shall terminate in a
rain- and insect-resistant fitting.
3.4.6
Concealed Piping in Buildings
When installing piping which is to be concealed, unions, tubing fittings,
running threads, right- and left-hand couplings, bushings, and swing joints
made by combinations of fittings shall not be used.
3.4.6.1
Piping in Partitions
Concealed piping shall be located in hollow rather than solid partitions.
Tubing passing through walls or partitions shall be protected against
SECTION 15190A
Page 12
Previous Page
