BS 6400-2:2018 Specification for installation, exchange, relocation, maintenance and removal of gas meters with a maximum capacity not exceeding 6 m$u3/h Medium pressure (2nd family gases)

Gas-supply meters
Size
Volume flowmeters
Buildings
Position
Control devices
2nd family gases
Pressure
Installation
Safety measures
Domestic
Exchange
Flow rates
Flowmeters

Link: BS 6400-2:2018 Specification for installation, exchange, relocation, maintenance and removal of gas meters with a maximum capacity not exceeding 6 m$u3/h Medium pressure (2nd family gases)
Source: BSI Standards