Industry Standard Update 132

IGEM/G/1 Edition 3 – Defining the boundaries between the Network, primary meter installation and installation pipework

Date issued: 19 January 2026

This Industry Standard Update provides an overview of the recently published revised Industry Standard IGEM/G/1 Edition 3 – Defining the boundaries between the Network, primary meter installation and installation pipework, and highlights areas of significant change that the revision has introduced.

Introduction

During November 2025, IGEM published a revision to IGEM/G/1 Edition 2 Defining the end of the Network, a meter installation and installation pipework(1). IGEM/G/1 Edition 3 – Defining the boundaries between the Network, primary meter installation and installation pipework(2) (Communication 1902) supersedes Edition 2 (Communication 1765), which is now obsolete.

The following is a brief overview of the amendments made in IGEM/G/1 Edition 3.

General

As well as the title, the standard has been updated to give a broader and clearer scope, with explicit focus on the three distinct boundary interfaces rather than just the end of the network. 

There is a shift from a single end point to a boundary-based framework, with the term ‘end of network’ being replaced with ‘boundaries of the network’.

Section 4: Primary definitions

Some of the definitions in Section 4 have been expanded, primarily that of an Emergency Control Valve (ECV). Where previously there was limited guidance for complex sites or multi-building premises, there is  now expanded guidance for these types of installation. 

Additionally, the terms Thermal Cut Off valves (TCO) and Excess Flow Valves (EFV) have been introduced to the standard, with the requirements of the valve when included in an installation. Where installed, both valves shall be deemed part of the ECV.

Section 6: Standard and legacy gas supply arrangements

This section has been expanded to include new installations that do not meet the requirements for standard supply arrangements. It states that while any new installation should normally have to comply with the requirements of a relevant standard, not all new installations are able to meet these where an existing onward distribution system exists downstream of the primary meter installations. Wherever deviation is required, certain conditions must be met, which are given in this section. 

Legacy sub-deduct arrangements are no longer acceptable and need to be reported to the relevant gas transporter (GT).

Summary

As previously stated, this Industry Standard Update is only a brief overview of the information contained in the amended standard. Registered businesses should be aware that they have a responsibility to ensure that they are fully apprised of all the requirements of the whole published standard and its practical application.

Bibliography

(1) IGEM/G/1 – Edition 2 – Defining the end of the Network, a meter installation and installation pipework (Communication 1765).

(2) IGEM/G/1 – Edition 3 – Defining the boundaries between the Network, primary meter installation and installation pipework (Communication 1907)