3.11
BUILDING STRUCTURE
Building structure shall not be weakened by the installation of any gas
piping. Beams or joists shall not be cut or notched. Piping supports
shall not be attached to metal decking. Supports shall not be attached to
the underside of concrete filled floors or concrete roof decks unless
approved by the Contracting Officer.
3.12
PIPING SYSTEM SUPPORTS
Gas piping systems in buildings shall be supported with pipe hooks, metal
pipe straps, bands or hangers suitable for the size of piping or tubing.
Gas piping system shall not be supported by other piping. Spacing of
supports in gas piping and tubing installations shall conform to the
requirements of NFPA 54. The selection and application of supports in gas
piping and tubing installations shall conform to the requirements of MSS
SP-69. In the support of multiple pipe runs on a common base member, a
clip or clamp shall be used where each pipe crosses the base support
member. Spacing of the base support members shall not exceed the hanger
and support spacing required for any of the individual pipes in the
multiple pipe run. The clips or clamps shall be rigidly connected to the
common base member. A clearance of 3.2 mm 1/8 inch shall be provided
between the pipe and clip or clamp for all piping which may be subjected to
thermal expansion.
3.13
ELECTRICAL BONDING AND GROUNDING
The gas piping system within the building shall be electrically continuous
and bonded to a grounding electrode as required by NFPA 70. Conventional
flange joints allow sufficient current flow to satisfy this requirement.
3.14
SHUTOFF VALVE
Main gas shutoff valve controlling the gas piping system shall be easily
accessible for operation and shall be installed as indicated, protected
from physical damage, and marked with a metal tag to clearly identify the
piping system controlled.
3.15
CATHODIC PROTECTION
**************************************************************************
NOTE: Designs are required to have cathodic
protection for underground ferrous gas piping
regardless of soil condition. Other guidance is
available in TM 5-811-7. Additions to existing
systems will be provided with cathodic protection.
Stations will be provided for testing the cathodic
protection system.
**************************************************************************
Cathodic protection shall be provided for underground ferrous gas piping as
specified in [Section 13110A CATHODIC PROTECTION SYSTEM (SACRIFICIAL
ANODE)] [Section 13112A CATHODIC PROTECTION SYSTEM (IMPRESSED CURRENT)].
3.16
TESTING
Before any section of a gas piping system is put into service, it shall be
carefully tested to assure that it is gastight. Prior to testing, the
SECTION 15190A
Page 16
Previous Page
