1.1 This Specification is part of a series of Institution of Gas Engineers and Managers (IGEM) publications, providing a specification for selecting meter connectors. 
 
1.2  British Gas and latterly, National Grid Metering (NGM) developed a series of specifications for key metering components based on its own suite of product requirements. These documents were made available to meter installers and purchasers under the title of Pressure Regulator Specification (PRS) 'e' documents. Originally these Specifications were made available through Advantica, as they were known at the time. 
 
NGM has transferred the ownership of these documents to IGEM to make them available to the wider industry. It is some years since the original 'e' documents were updated and these have been withdrawn.  
 
1.3  This Specification has been drafted by an IGEM Working Group, appointed by IGEM’s Gas Measurement Committee, and has been approved by IGEM’s Technical Coordinating Committee on behalf of the Council of IGEM. 
 
1.4  Manufacturers supplying connectors for gas meters for gas flow rates not exceeding 6 m³ h-1 and inlet pressures not exceeding 75 mbar and not exceeding 2 bar are to conform to the requirements of this Specification and to any other relevant documents to which reference is made herein. 
 
1.5  Details on the installation of domestic-sized gas meters and associated components are given in BS 6400-1. 
 
1.6  Terms such as “maximum operating pressure” (MOP), “maximum incidental pressure” (MIP) and “operating pressure” (OP) are used to reflect gas pressure terminology used in European standards. These terms will arise in all relevant IGEM Standards and, possibly, in other standards. Other terms have been introduced to assist in recognition of design information to be transferred between interested parties. 
 
1.7 This Specification makes use of the term “must”, “shall” and “should” when prescribing particular procedures.  

• the term “must” identifies a requirement by law in Great Britain (GB) at the time of publication 
• the term “shall” prescribes a procedure which, it is intended, will be complied with in full and without deviation 
• the term “should” prescribes a procedure which, it is intended, will be complied with unless, after prior consideration, deviation is considered to be acceptable. 

 
Such a term may have different meanings when used in legislation, or Health and Safety Executive (HSE) Approved Codes of Practice (ACoPs) or guidance, and reference needs to be made to such statutory legislation or official guidance for information on legal obligations. 
 
1.8    New and improved practices may be adopted prior to this Specification being updated. Amendments to this Specification will be issued when necessary and their publication will be announced in the Journal of IGEM and elsewhere as appropriate. 
 
1.9    Requests for interpretation of this Specification in relation to matters within its scope, but not precisely covered by the current text, should be addressed to Technical Services, IGEM, IGEM House, High Street, Kegworth, Derbyshire, DE74 2DA. Such requests will be submitted to the relevant Committee. Any advice given by or on behalf of IGEM does not imply acceptance of any liability, and does not relieve any party of their obligations. 
 
1.10    This Specification was published in December 2016.