Public Consultation: Gas Distribution Mains
NSAI has launched a public consultation for the draft I.S. 329:2024 A1:2025 Gas distribution mains
Public consultation period: From 31/07/2025 until 01/09/2025, inclusive.
The scope of the draft I.S. 329:2024 A1:2025 Gas distribution mains
This Standard specifies the minimum requirements for the design, construction, commissioning, operation, maintenance and alteration of mains, for the distribution of 1st, 2nd and 3rd family gases, natural gas and substitute natural gas, (e.g. Bio-methane gas) as classified in I.S. EN 437 at pressures up to and including 16 bar, and decommissioning.
The distribution mains is the network of pipes which transports gas from the natural gas transmission system (see I.S. 328), LPG storage system or a gas manufacturing plant to the gas service pipes.
In a new Annex C, this Standard specifies the minimum requirements for the design, construction, commissioning, operation, maintenance and alteration, and decommissioning of new mains for the distribution of 100 % hydrogen at pressures up to and including 5 bar. It does not apply to proving tests for 100 % hydrogen, except to require that hydrostatic tests not be carried out.
This Standard does not apply to the installation of transmission systems, (see I.S. 328), LPG storage systems (see I.S. 3216) or gas manufacturing plants.
This Standard does not apply to the installation of gas service pipes, (see S.R. 12007-5 and I.S. EN 12007-5).
All pressures quoted in this Standard are gauge pressures.
Content of the draft:
The draft contains the following sections:
- Section 1 Scope
- Section 2 Normative References
- Section 3 Terms and definitions
- Section 4 Functional requirements for gas pipelines and installations
- Section 5 Quality and safety
- Section 6 Materials and components
- Section 7 Design
- Section 8 Construction
- Section 9 Jointing
- Section 10 Proving tests
- Section 11 Alterations to live mains
- Section 12 Commissioning and decommissioning
- Section 13 Protection against environmental degradation
- Section 14 Monitoring of the gas infrastructure
- Section 15 Operation and maintenance
- Section 16 Records
- Section 17 Additional measures when dealing with Liquefied Petroleum Gas (LPG) systems
- Section 18 New pipeline used for 100 % hydrogen
- Annex A Purging criteria for natural gas and LPG
- Annex B Polyethylene fusion joint integrity
- Annex C New mains for 100 % hydrogen
View the draft and submit comments:
All interested parties are invited to comment on the draft I.S. 329:2024 A1:2025 through the NSAI ‘Your Standards, Your Say’ forum: https://www.nsainep.ie/Home/Details/34682
NSAI would like to acknowledge the following organisations for their contribution to the development of this draft standard:
- Gas Networks Ireland (GNI),
- Calorgas,
- Commission for Regulation of Utilities (CRU),
- Jacobs,
- Liquid Gas Ireland (LGI),
- Active Energy Control Ltd (AEC),
- Pipelife,
- Fingleton White
Find out how to use Your Standards, Your Say here - https://www.nsai.ie/standards/your-standards-your-say/
[Disclaimer: All reasonable effort was made to ensure that the information on this page was correct at the time of publication. Any views or opinions expressed on this page are not necessarily those of NSAI. NSAI accepts no responsibility or liability howsoever arising from the contents of this publication or any errors, inaccuracies, or omissions in the contents of the information provided therein.]
