BS 6400-2:2018

The British Standards InstitutionThis British Standard specifies requirements for the installation, exchange, relocation, maintenance and removal of credit or prepayment or smart meters of the following types: diaphragm, ultrasonic and thermal mass gas meters with a maximum capacity not exceeding 6 m3/h.

This British Standard specifies requirements for the installation, exchange, relocation, maintenance and removal of credit or prepayment or smart meters of the following types: diaphragm, ultrasonic and thermal mass gas meters with a maximum capacity not exceeding 6 m3/h. NOTE1 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. NOTE2 For smart meters this standard only covers the associated gas work. This part of BS6400 is applicable to primary meter installations: supplied with 2nd family gases from medium pressure gas distribution systems with a maximum operating pressure exceeding 75 mbar but not exceeding 2 bar and with a design maximum incidental pressure of 2.7 bar; NOTE3 Some legacy MP networks can operate at a design minimum pressure (DMP) of 35 mbar, 65 mbar, 105 mbar, 180 mbar and 270mbar. only fitted downstream of the emergency control valve; that utilize a pressure control and protection system contained within a regulator assembly that is downstream of the emergency control valve; where all gas fittings subjected to medium pressure have been pre-assembled and where strength and gas tightness testing has been undertaken on the regulator assembly at the factory; NOTE4 It is recognized that the final connection(s) to the gas service would not be subject to a strength test. where the operating pressure at the outlet of the meter is nominally 21 mbar; and installed external to the building. NOTE5 Installation, exchange, relocation, maintenance and removal of a secondary meter with a maximum capacity of 6 m3/h is specified in BS6400‑1. NOTE6 Installation pipework is specified in BS6891. NOTE7 Service pipes (including the emergency control valve) are specified in the Institution of Gas Engineers and Managers’ publication on gas services, IGE/TD/4 [18]. NOTE8 All pressures quoted in this standard are gauge pressures and all pressure absorption values are for natural gas unless otherwise specified. NOTE9 Additional guidance on domestic gas systems can be found in the European functional standards BSEN1775 and BSEN12279. NOTE10 Additional guidance on measuring systems can be found in the European functional standard BSEN1776.