Jump to main content

Planning hydrogen plants

The most important standards and guidelines for maximum safety, quality and efficiency

The construction of a hydrogen plant is extremely demanding. Good and thorough planning is the be-all and end-all. Economic, technical and legal aspects must therefore be considered in advance - from the choice of location and technology to environmental compatibility. Safety is also a key issue when handling the highly flammable gas. Every machine component in the plant must comply with the generally applicable regulations for hydrogen. This guide presents the most important standards and guidelines that need to be observed when planning and realising hydrogen plants.

1. Safety and design requirements

Numerous safety and design requirements must be observed for applications with hydrogen - whether for pipework or electronic systems, for example. They play a crucial role in ensuring safety, efficiency and compliance.

The document provides guidelines for the design, construction and safe operation of pipelines transporting pure hydrogen and hydrogen mixtures. Design and inspection techniques are also recommended for dealing with stress corrosion cracking.

The international standard for electrical, electronic and programmable electronic systems defines general requirements for functional safety. It forms the basis for many sector-specific SIL standards.

The Machinery Directive aims to guarantee a high level of health and safety protection during the operation of machinery. It lays down essential requirements that manufacturers must fulfil before placing machinery on the market in the EU. Key words: EC Declaration of Conformity and CE labelling. The directive applies to machinery, chains and electric drives, among other things.

2. Material selection and evaluation

The selection and evaluation of materials for hydrogen applications requires a great deal of expertise, especially when it comes to safety and durability. Various standards and guidelines provide detailed instructions on this.

The guidelines describe various suitable metallic materials such as alloy steels, stainless steels, nickel alloys as well as copper and cobalt alloys and general information on plastics.

The standard contains requirements for the compatibility of materials for gas cylinders and accessories with hydrogen. It supports the selection of materials that do not become brittle or corrode due to the gas.

This standard also specifies guidelines for material selection. It requires metallic materials to be resistant to corrosion and stress cracking in environments containing H₂S. See also hydrogen embrittlement.

3. Explosion protection and electrical safety

Explosion protection and electrical safety are key aspects in hazardous areas and when using electrical devices. Various directives, such as the ATEX Directive and the Low Voltage and EMC Directives, provide comprehensive specifications in this regard.

The directive deals with the explosion protection of equipment and protective systems in potentially explosive atmospheres. It applies to devices that are potential ignition sources, as well as to their components and safety devices.

The Low Voltage Directive specifies safety requirements for electrical appliances with a rated voltage of 50-1000 V AC or 75-1500 V DC. The EMC Directive in turn ensures that electrical and electronic equipment is electromagnetically compatible and does not cause harmful interference.

4. Pressure vessels and pipework

Pressure vessels and pipelines are subject to numerous specifications that are decisive for the safe operation and material requirements of these components.

EIGA IGC 121/14 provides specific guidelines for the use of hydrogen pipelines. See also category 1 "Safety and design requirements" and 2 "Material selection and assessment".

The directive sets requirements for the design, manufacture and conformity assessment of pressure equipment and assemblies with a maximum permissible pressure of more than 0.5 bar.

The standard describes the requirements that apply to the materials for industrial pipework and its supports made of metallic materials in accordance with EN 13480-1. Also relevant for hydrogen applications.

This code applies to pipelines and lines that are operated with gaseous hydrogen, hydrogen mixtures or liquid hydrogen. It also specifies requirements for the connection points between the pipelines and the associated pressure vessels.

5. Testing and inspection

Regular tests and inspections are essential processes for ensuring the safety of systems and components. From the personnel to the individual components. Numerous standards specify requirements and procedures for this.

This standard focuses on the qualification and certification of personnel for non-destructive testing (NDT). They are important for checking the integrity and quality of materials and components in hydrogen plants without damaging them. The tests include the inspection of welds, pipes, vessels and other critical components.

This part of ISO 15848 describes test methods for assessing the external tightness of, among other things, body connections of shut-off valves and control valves that work with volatile air contaminants and hazardous liquids - essential for minimising leaks and improving plant safety.

The Machinery Directive specifies a number of testing and inspection requirements, including the conformity assessment procedure and the EC type examination. It also stipulates the creation of comprehensive technical documentation and operating instructions.

6. Environmental and health requirements

The area of environmental and health protection also provides a number of regulations that are central to the handling of hazardous substances such as hydrogen.

The protective measures of TRGS 500 define a framework for handling hazardous substances in the workplace in order to ensure the health and safety of employees. The STOP principle is applied here, which stands for substitution, technical, organisational and personal protective measures.

The REACH Regulation (Registration, Evaluation, Authorisation and Restriction of Chemicals) was issued by the European Union to improve the protection of health and the environment from the risks posed by chemicals. It obliges manufacturers and importers to prove the safety of chemicals by registering them and assessing their risks.

The CLP Regulation (Classification, Labelling and Packaging of Substances and Mixtures) implements the United Nations' Globally Harmonised System (GHS) in EU law. It harmonises the criteria for the classification of chemical substances and mixtures with regard to their health, environmental and physical hazards.

7. Requirements for hydrogen quality

The quality of the hydrogen is crucial for the safe and efficient operation of fuel cells and other applications. Standards such as ISO 14687 and DIN EN 17124 as well as DVGW Code of Practice G 260 define the requirements for the purity and quality of hydrogen.

This standard specifies the requirements for the quality of hydrogen used as fuel in proton exchange membrane fuel cells (PEMFC) for road transport. It defines degrees of purity and the maximum permissible concentrations of impurities such as carbon monoxide, sulphur compounds, ammonia and particles.

The European standard is based on the above-mentioned ISO 14687 and provides additional requirements and guidelines for quality assurance. It is intended to ensure a consistently high quality of hydrogen.

DVGW G 260 specifies requirements for the quality of gases that are transported and distributed in public gas supply networks. This includes natural gas, biogas, synthetic natural gas (SNG) and hydrogen.

8. Requirements of the network operators

The requirements for network operators are important for the integration of gases into the supply network. In accordance with Section 19 of the Energy Industry Act, Open Grid Europe GmbH specifies minimum technical requirements relating to the design, safety, inspection and maintenance of grid connections and gas pressure regulating and metering systems.

The minimum technical requirements of Open Grid Europe GmbH for grid connections and gas pressure regulating and metering stations include Design and safety standards (e.g. specifications for materials), control and safety mechanisms (e.g. use of pressure regulation technologies) as well as certifications and maintenance measures (e.g. fulfilment of safety certificates and inspections).

9. Feeding hydrogen into gas grids

Special technical and safety-related measures are required for feeding hydrogen into gas networks. Various DVGW worksheets such as G 485, G 262 and G 685 define these requirements.

The worksheet of the German Technical and Scientific Association for Gas and Water refers to the technical regulations for the maintenance and operation of gas pipelines. It focuses in particular on the safety and efficiency of feeding hydrogen into gas supply networks.

This worksheet deals with the utilisation of gases from renewable sources in the public gas supply. It deals with the guidelines for the feed-in and utilisation of biogas, synthetic methane and hydrogen in public gas supply networks. It also supports the integration of renewable gases - including hydrogen - into the existing gas infrastructure.

DVGW G 685 is a standard that defines specific requirements and guidelines for the injection of renewable gases such as hydrogen into gas supply networks. This standard deals with both the technical and safety aspects of feeding in gases from renewable sources.

Are you looking for competent contacts for your hydrogen project?

The planning and realisation of a hydrogen plant requires an in-depth understanding of the relevant standards and guidelines in order to ensure the highest safety, quality and efficiency standards. In addition to the guidelines listed above, there are many other standards that need to be taken into account when realising a hydrogen project.

A. Hock has already gained experience with the central guidelines in numerous projects, including HyBit and Battolyser. We will be happy to advise you about our entire valve, measurement and control technology product portfolio for your planned hydrogen system.

Andreas Schalwig

Andreas Schalwig

Technical Sales

I’m happy to help you with projects and enquiries in the field of valve technology as well as measurement and control technology. I have more than 15 years of experience in the dimensioning of control valves and actuators. What’s more, I help customers from all over the world to modernise their industrial plants.