This European Standard contains requirements for the production and testing of weld joints for the installation and modification of onshore steel pipelines and pipework used in gas infrastructure, including in-service pipelines, for all pressure ranges for the carriage of processed, non-toxic and non-corrosive natural gas according to EN ISO 13686 and for the carriage of non-conventional gases such as injected biomethane,
where
- the pipeline elements are made of unalloyed or low-alloyed carbon steel
- the pipeline is not located within commercial or industrial premises as integral part of the industrial process on those premises except for any pipelines and facilities delivering gas to such premises
- the pipework is not located within household installations according to EN 1775
- the design temperature of the system is between -40 °C up to and including 120 °C.
The onshore steel pipelines and pipework used in gas infrastructure include in-service pipelines, for all pressure ranges for the carriage of processed, non-toxic and non-corrosive natural gas according to EN ISO 13686 and for the carriage of non-conventional gases complying with EN ISO 13686, and for which a detailed technical evaluation of the functional requirements (such as injected biomethane) is performed ensuring there are no other constituents or properties of the gases that can affect the integrity of the pipeline.
This standard is not applicable to welds produced prior to the publication of this European Standard.
Table 1 assigns the application areas to quality requirement categories as a function of the working pressure and pipe materials used.
Additional requirements may be specified when, for example:
- the strain on pipelines and systems,
- the materials,
- the line routing,
- the design or the welding technique
are considered critical.
This European Standard specifies common basic principles for gas infrastructure. Users of this European Standard should be aware that there can exist more detailed national standards and/ or codes of practice in the CEN member countries.
This European Standard is intended to be applied in association with these national standards and/ or codes of practice setting out the above-mentioned basic principles.
In the event of conflicts in terms of more restrictive requirements in national legislation/ regulation with the requirements of this standard, the national legislation/ regulation takes precedence as illustrated in CEN/ TR 13737 (all parts).

NOTE CEN/ TR 13737 (all parts) contains:
- clarification of relevant legislation/ regulations applicable in a country
- if appropriate, more restrictive national requirements
- national contact point for the latest information.