Specification for installation, exchange, relocation and removal of gas meters with a maximum capacity not exceeding 6 m3/h - Low pressure (2nd family gases)
This standard specifies requirements for the installation, exchange,
relocation and removal of credit or prepayment diaphragm and
ultrasonic gas meters with a maximum capacity not exceeding 6 m3/h.
NOTE 1 For the purposes of this standard, installation includes design,
inspection and commissioning. It is recognized that each of these tasks can
be performed by the same person.
This part of BS 6400 is applicable to primary and secondary meter
installations:
a) supplied with 2nd family gases from low pressure gas distribution
systems with a maximum operating pressure not exceeding
75 mbar, a design minimum pressure of 19 mbar and a design
maximum incidental pressure of 200 mbar;
b) only fitted downstream of the emergency control valve;
c) that utilizes a primary meter regulator downstream of the
emergency control valve;
d) where the operating pressure at the outlet of the meter is
nominally 21 mbar.
NOTE 2 Low pressure gas networks in Great Britain operate with a
maximum operating pressure not exceeding 75 mbar, a design minimum
pressure of 19 mbar and a design maximum incidental pressure of
200 mbar.
Installation pipework is specified in BS 6891.
Service pipes (including the emergency control valve) are specified in
the Institution of Gas Engineers and Managers’ publication on gas
services, IGE/TD/4 [13].
NOTE 3 All pressures quoted in this standard are gauge pressures and
all pressure absorption values are for natural gas unless otherwise
specified.
NOTE 4 Additional guidance on domestic gas systems can be found in
the European functional standards BS EN 1775 and BS EN 12279.