This DVGW-Information GAS No. 17 provides information on how to implement the lightning protection requirements in accordance with IEC 62305 for systems of gas and hydrogen transport and distribution systemas well as for systems supplying commercial, industrial or comparable facilities. Lightning protection measures are used to protect people, structures and technical equipment against the effects of lightning.

This Guideline G 655 was developed by the project group “H2 Readiness for Gas Installation” within the Technical Committee “Gas Installation” with the involvement of representatives from Technical Committees “Domestic, Commercial, and Industrial Gas Applications”, “Components and Auxiliary Materials – Gas”, as well as of “Infrastructure Gas Mobility”. According to the German Energy Industry Act (“Energiewirtschaftsgesetz”; EnWG) Article 3 No 10c und No 19a the injection of hydrogen and other renewable gases is permissible. In combination with Article 49 of the Energy Industry Act, the DVGW Sets of Rules and, specifically, the technical rules Code of Practice G 260 “Gas Quality”, for domestic installations still G 600 “Technical Rule for Gas Installations” (DVGW TRGI) and G 614-1 “Above-Ground Gas Pipelines on Premises behind Point of Delivery — Design, Con-struction, Testing and Commissioning” shall be taken into account.  According to DVGW Code of Practice G 262:2011-09 “Usage of Gases from Regenerative Sources in the Supply of the General Public with Gas”, the injection of < 10 vol% hydrogen has been admissible. The revision of DVGW G 260:2020-09 (draft) and entailed fusion with DVGW G 262 (A) has laid the basis for the injection of hydrogen of up to 20 vol%. In principle, the injection with such a volume was already possible through applying a corresponding exception in DVGW G 260 (A):2013 Section 4.2.2 “Relative Density” and carrying out pre-acceptance testing in case values fell below the relative density. To make “pure” hydrogen networks possible, an amendment of the Energy Industry Act is currently being developed which will integrate pure hydrogen networks into the Act. There, the DVGW Sets of Rules are referenced as the generally accepted state-of-art. This Guideline further expands the DVGW sets of rules for hydrogen-rich natural gas of up to 20 vol% H2’ or hydrogen in the context of a two-step process. In the first step, “H2 Guidelines” are developed for the fields “gas infrastructure” and “gas utilisation” which describe the protection objectives for hydrogen-rich natural gases and hydrogen that must be adhered to and that supplement the existing sets of rules. The goal is to expand the scope of application of DVGW Sets of Rules to natural gas/hydrogen mixtures or pure hydrogen. The process includes advice and rec-ommended actions that make e.g., the realization of pilot projects or conducting individual certified ac-ceptance tests possible. In the second step, the respective national and European rulesets are revised and adjusted in detail with consideration towards the results of parallelly occurring F&E activities. In some sections, only generalized specifications or notes are currently possible. As soon as new state of knowledge exists, these generalized items will be specified with more precision.  

This Guideline G 464 shall apply for the fracture mechanical assessment of steel gas pipelines that already exist or are projected for construction with a design pressure of more than 16 bar for the transportation or distribution of gases of the 5th gas family (hydrogen) as specified by DVGW Code of Practice G 260. This present Guideline G 464 addresses the assessment of an assumed defect; for the assessment of measured defects, the guideline can be applied analogously.

This guideline G 408 shall apply to the conversion of pipelines made from plastic to hydrogen-containing, methane-rich gases (2nd gas family) or hydrogen (5th gas family) in accordance with DVGW Code of Practice G 260 up to an operating pressure of 16 bar and ends with the main shut-off valve, the thematic threshold to DVGW Guideline G 655. This guideline G 408 can also be applied to the conversion of plastic gas pipeline operated with gases that do not conform to the specifications of DVGW Code of Practice G 260 if the gases’ specific characteristics and, if applicable, other existing regulations are taken into account. The respective guidelines on pipeline conversion shall be consulted for networks using different pipeline materials (e.g., plastic and steel).

This guideline G 407 shall apply to the conversion of pipelines made from steel to hydrogen-containing, methane-rich gases (2nd gas family) or hydrogen (5th gas family) in accordance with DVGW Code of Practice G 260 up to an operating pressure of 16th and ends with the main shut-off valve, the custody transfer point to DVGW G 600 (A), respectively to G 614.1 (A) (including the additions detailed in DVGW Guideline G 655). This guideline can also be applied to the conversion of steel gas pipeline operated with gases that do not conform to the specifications of DVGW Code of Practice G 260 when taking into account the gases’ specific characteristics and, if applicable, other existing regulations. The respective guidelines on pipeline conversion shall be consulted for networks using different pipeline materials (e.g., plastic and steel).

For hydrogen transmission within the German gas grid, it is imperative to obtain a clearly defined assessment of steel components for hydrogen suitability and relevant implementation in the DVGW Codes of Practice. Within this context, DVGW Code of Practice G 409 (for the conversion of pipelines to hydrogen transmission) and DVGW Code of Practice G 463  (for the construction of new pipelines), for example, have been specifically aligned to hydrogen as a transmission medium. Both these codes of practice may require a fracture-mechanical assessment of pipelines and pipeline components, with fracture-mechanical parameters beingrequired as input variables. So far, it was only in ASME B 31.12 [3] that these parameters were specified in an international code of practice. They specifically involve minimum fracture toughness (KIc) and the description of crack toughness (da/dN) with hydrogen as a medium. However, the parameters specified in ASME B 31.12 were based on investigations on US materials which are verysimilar, but not identical, to the materials used in Germany and elsewhere in Europe. Furthermore, the conversion of existing older natural gas pipelines (comprising older materials) is of very considerable interest particularly for the scope of application of the DVGW Code of Practice, although a direct transferability of the US investigations was considered to be problematic. Hence, within the context of the DVGW’s extensive SyWeSt H2 research project, fracturemechanical investigations were performed specifically for the pipeline steel grades used in Germany (and, in some cases, elsewhere in Europe) with hydrogen as a medium. The objective of this project was to compare the established fracture-mechanical parameters with the results on which ASME B 31.12 is based for the purpose of validating their application to steel grades used in Germany and, where applicable, drawing up a modified correlation for crack growth.

In recent years, the relevant DVGW Codes of Practice and associated information sheets for carrying out and evaluating the above-ground inspection of natural gas pipelines have been revised. In addition, measurement technology and data processing (digitisation) have developed constantly. For the above-ground inspection of buried pipelines in the distribution network through inspections and drives, new measurement methods are increasingly being used. In the EvaNeMeL research project, these new measurement methods were evaluated both theoretically and through experimental investigations. Five vehicle-mounted measurement systems and three hand-held remote gas detection methods were investigated. The results demonstrate the performance of the novel methods against a benchmark and also to serve as a basis for a subsequent supplement to the DVGW rules and regulations for above-ground inspection. The benchmark was an experienced “Gasspuerer” (gas safety personnel) who carried out a walk-through with a probe-based PortaFID M3K in parallel to the experimental investigations. This established walk-through of buried pipelines results in a high level of safety for the public gas supply.

In conjunction with DIN EN 1594, this Technical Rule G 463 applies to the planning and construction of steel high pressure gas pipelines with a design pressure of more than 16 bar for supplying gas to the general public as well as to connected energy facilities on company premises and in the field of commercial gas application of gases of the 2nd and 5th gas family as defined by DVGW Code of Practice G 260. The scope of application has no upwards limitation in terms of the technical parameters nominal diameter and design pressure. This Technical Rule can be applied mutatis mutandis to the construction of high pressure gas pipelines which do not conform to the specifications of DVGW Code of Practice G 260, provided that the specific characteristics of the gases or, if applicable, other already existing technical sets of rules are taken into account.

This Draft of Code of Practice C 260 helps to ensure the safety and health protection of persons as well as the technical integrity of pipelines, systems and system components for transporting CO₂ in pipelines made of steel pipes. C 260 Draft Code of Practice specifies requirements for the composition of CO₂ and CO₂ streams. It establishes the framework conditions for the supply, transportation, distribution, storage and operation of systems and appliances and for commercial and industrial applications that are planned, built and operated in accordancewith the DVGW regulations (C series). It forms the basis for development, standardization and testing. This Draft of Code of Practice C 260 describes the characteristics and requirements for the properties of a carbon dioxide stream for transportation in steel pipelines and also contains recommendations and information on the effects of CO₂ streams on the design and operation of CO₂ pipeline transportation systems. CO₂ streams within the meaning of this regulation originate from capture processes and are transported to storage sites or for further utilization. The capture processes are either upstream or downstream of the actual power plant or industrial process. The following sources and emitters may be considered, for example: Power plant processes: Gas-fired power plants Thermal waste treatment Biomass power plants Power plants with integrated gasification Industrial processes: Steel production Biomethane production Cement production Building material production Lime production Chemical industry Glass production Foundries The different sources of CO₂ streams result in different compositions, which in turn have a major influence on the design and operation of CO₂ transport pipelines. In the following, the possible influences and consequences of accompanying substances for transportation in steel pipelines are described in more detail. The behaviour and transport of impurities within CO₂ streams described in this document has, where it is available, been based on experimental or operational experience. Where this experience is not currently available, a conservative figure has been used, based, for instance, on theoretical modelling. Once appropriate experience has been gained it is expected to raise some permissible levels so that unnecessary processing expense can be avoided.

The DVGW set of rules G 414 for the installation (planning, building and commissioning) of gas pipework focuses on buried gas pipework; it contains only few instructions to be observed when installing above-ground gas pipework.

This standard G 493-2 encompasses personal and professional requirements for companies providing maintenance for gas plants and installations that fall within the scope of DVGW G 495 (A), as well as biogas injection and refeeding plants as specified by DVGW G 265-2 or hydrogen injection plants as specified by DVGW G 265-4 (M).Companies which, within the context of comprehensive plant management, either as original operators or as contractors, are responsible for the maintenance of energy plants, and possess the required personal qualification and organization according to DVGW G 1000 (A), may conduct the maintenance of gas plants without certification as defined by this standard within the network which they have the abovementioned responsibility for. The prerequisite for the maintenance without certification as mentioned above is that the expert and tech-nical conditions detailed in this standard are met by the company’s own workforce or by service providers with a TSM certification or other corresponding certifications. The company shall appoint the experts re-sponsible for maintenance in writing. The fulfilment of these conditions can be verified e.g. during a TSM review according to DVGW G 1000 (A).

This Technical Rule G 492 governs planning, manufacturing, assembly, testing, commissioning and operation, as well as decommissioning and disposal of gas measuring systems of up to 100 bar1 in gas transportation and distribution systems and stations supplying commercial, industrial, or other comparable facilities.

Code of Practice GW 315 provides essential information on how to avoid damaging to existing supply systems during construction operations. It applies to all construction work  and regulates the requirements for construction contractors and operators of supply systems.

This document ISO 17885 specifies the requirements for mechanical fittings for joining plastic piping systems for the supply of gaseous fuels, the supply of water for human consumption and other purposes, as well as for industrial application. It provides a unified set of test methods to check the performance of the fittings, depending on their intended use. It is the responsibility of the purchaser or specifier to select the appropriate fitting, taking into account their particular requirements and any relevant national guidance or regulations and installation practices or codes.

This Technical Rule G 260 specifies the requirements for the quality of fuel gases used in the supply of the general public with gas and sets the parameters for gas delivery, gas transportation, gas distribution, gas storage, operation of gas plants/systems and gas appliances for commercial and industrial gas applications as well as for development, standardization, and testing. Gases transported in separate pipelines which are not used in the supply of the general public, or are used as energy carrier or resource, and/or are used in special gas appliances are not subject to the scope of this Technical Rule.

G 452‑3 Technical Information ‑ Guideline 03/2021