Safety requirements related to the end-user equipment

This LAP is concerned with the safety requirements (and design and operation aspects) for commercial and domestic end user equipment operating with hydrogen gas blends resulting from hydrogen injected and distributed in the local gas grid at the DSO level

Glossary:

The requirements needed to guarantee the safety of the end user application.
Is it a barrier?
Yes
Type of Barrier
Structural barriers, Operational barriers, Economic barriers, Regulatory gap
Assessment Severity
1

Questions:

Question 1 Is there any legislation with regard to safety requirements related to end-user equipment (e.g.: limits in terms of H2 for use in gas appliances)? If yes, please answer the following question.
The threshold for the hydrogen amount in natural gas is 4% (Mol). This threshold is stated in the Austrian standard:/guideline ÖVGW 31 respectively ÖVGW 33
Question 2 Changes to gas supply composition may have implications for gas appliances (safety) and the relevant legislation. What are the implications you expects with regard to the possible concentrations of hydrogen in the H2NG blend?
Basically the direct changes of the safety requirements are not that big – in particular when taking the threshold of the hydrogen amount in the mixture as given. The implications are to be expected more from the billing perspective (the customer pays for the gross calorific value and not for the consumed volume) and regarding the Wobbe Index. The Wobbe index is linked with the gross calorific value and is an indicator for the required nozzle. In case there is a wrong nozzle installed one could generate local hot spots and ruin the device. Of course there will be a need for sensors which are either able to detect both gases – so natural gas and hydrogen or 2 sensors – one for the detection of natural gas the other one for the detection of hydrogen.
Question 3 For which end user applications do you foresee the main consequences and at which level? Could you please provide references to underpin your opinion?
Regardless whether one deals with ICEs or heating boilers or gas turbines, the Wobbe Index is crucial in order to generate the required flame size, flame form and flame temperature in order to avoid local hot spots which can ruin the material which is in contact with the flame; besides the efficiency would suffer if the Wobbe index is not “transformed” to the proper nozzle. In Austria the gas quality is the same in the entire so called market area East hence so far all of the gas consuming devices were sold with the same nozzle (of course adapted to the power of the device) In case of change of the gas quality in the entire market area East, all of the nozzles have to be adapted
Question 4 Safety is the main topic with regard to the use of applications. Which additional safety precautions needed do you foresee? Could you please provide references to underpin your opinion?
Regardless whether one deals with ICEs or heating boilers or gas turbines, the Wobbe Index is crucial in order to generate the required flame size, flame form and flame temperature in order to avoid local hot spots which can ruin the material which is in contact with the flame; besides the efficiency would suffer if the Wobbe index is not “transformed” to the proper nozzle. Of course there will be a need for sensors which are either able to detect both gases – so natural gas and hydrogen or 2 sensors – one for the detection of natural gas the other one for the detection of hydrogen
Question 5 Changes to gas supply composition may have implications for CNG compression, storage, and use in CNG vehicles. What are the additional safety precautions needed? Could you please provide references to underpin your opinion?
Basically the direct changes of the safety requirements are not that big – in particular when taking the threshold (4%) of the hydrogen amount in the mixture as given. The implications are to be expected more from the billing perspective (the customer pays for the gross calorific value and not for the consumed volume) and regarding the Wobbe Index. The Wobbe index is linked with the gross calorific value and is an indicator for the required nozzle. In case there is a wrong nozzle installed one could generate local hot spots and ruin the device. Regardless whether one deals with ICEs or heating boilers or gas turbines, the Wobbe Index is crucial in order to generate the required flame size, flame form and flame temperature in order to avoid local hot spots which can ruin the material which is in contact with the flame; besides the efficiency would suffer if the Wobbe index is not “transformed” to the proper nozzle. Of course there will be a need for sensors which are either able to detect both gases – so natural gas and hydrogen or 2 sensors – one for the detection of natural gas the other one for the detection of hydrogen. When it comes to compression of mixtures (natural gas and hydrogen) one has to take into account the high diffusion rate of hydrogen, hence the material of the bundles has to be adapted to this requirements. Of course the couplings and fittings and other screwed connections have to take care of the high diffusion rate of hydrogen as well.
Describe the comparable technology and its relevance with regard to hydrogen
Natural gas

National legislation:

EU Legislation:

  • Regulation (EU) 2016/426 of the European Parliament and of the Council of 9 March 2016 on appliances burning gaseous fuels and repealing Directive
    This Regulation applies to appliances burning gaseous fuels used for cooking, refrigeration, air-conditioning, space heating, hot water production, lighting or washing, and also forced draught burners and heating bodies to be equipped with such burners and to safety devices, controlling devices or regulating devices and sub-assemblies thereof, designed to be incorporated into an appliance or to be assembled to constitute an appliance (fittings).

    Article 7 sets the obligations of manufacturers which should inter alia:
    • ensure that appliances and fittings meet the essential requirements set out in Annex I.
    • draw up the technical documentation referred to in Annex III (‘technical documentation’)
    • carry out the relevant conformity assessment procedure
    • keep the technical documentation and the EU declaration of conformity for 10 years
    • ensure that procedures are in place for series production to remain in conformity
    • carry out sample testing of appliances made available on the market,
    • investigate, and, if necessary, keep a register of complaints, of non-conforming appliances and fittings and recalls of such appliances and fittings, and shall keep distributors informed of any such monitoring.
    • ensure that their appliances and fittings bear a type, batch or serial number or other element allowing their identification, and the inscriptions provided for in Annex IV.
    • indicate on the appliance their name, registered trade name or registered trade mark, and the postal address at which they can be contacted
    • ensure that the appliance or fitting is accompanied by instructions and safety information
    • ensure that the fitting is accompanied by a copy of the EU declaration of conformity containing, inter alia, instructions for incorporation or assembly, adjustment, operation and maintenance
    • take corrective measures necessary to bring that appliance or fitting into conformity, to withdraw it or recall it, if appropriate.
    • where the appliance or the fitting presents a risk, immediately inform the competent national authorities giving details, in particular, of the non-compliance and of any corrective measures taken
    • provide competent national authority with all the information and documentation necessary to demonstrate the conformity of the appliance.

    Article 9 sets obligations for importers which should inter alia:
    • ensure that the appropriate conformity assessment procedure has been carried out
    • ensure that the manufacturer has drawn up the technical documentation, that the appliance bears the CE marking and is accompanied by instructions and safety information and that the manufacturer has complied with the requirements set out in Article 7(5) and (6).
    • indicate on the appliance their name, registered trade name or registered trade mark, and the postal address at which they can be contacted
    • ensure that the appliance is accompanied by instructions and safety information in accordance with point 1.5 of Annex I, in a language which can be easily understood by consumers and other end-users, as determined by the Member State concerned.
    • ensure that the fitting is accompanied by a copy of the EU declaration of conformity containing, inter alia, instructions for incorporation or assembly, adjustment, operation and maintenance in accordance, in a language which can be easily understood by appliance manufacturers, as determined by the Member State concerned.
    • ensure that, while an appliance or a fitting is under their responsibility, storage or transport conditions do not jeopardise its compliance with the essential requirements
    • carry out sample testing of appliances made available on the market, investigate, and, if necessary, keep a register of complaints, of non-conforming appliances and fittings and recalls of such appliances and fittings, and shall keep distributors informed of any such monitoring.
    • for 10 years after the appliance or the fitting has been placed on the market, keep a copy of the EU declaration of conformity at the disposal of the market surveillance authorities and ensure that the technical documentation can be made available to those authorities, upon request
    • further to a reasoned request from a competent national authority, provide it with all the information and documentation necessary to demonstrate the conformity of an appliance or a fitting in a language which can be easily understood by that authority

    Article 10 sets the obligations of distributors which should inter alia:
    • verify that the appliance bears the CE marking and that it is accompanied by instructions and safety information and that the manufacturer and the importer have complied with the requirements set out in Article 7(5) and (6) and Article 9(3) respectively
    • not make the appliance or the fitting available on the market until it has been brought into conformity.
    • ensure that, while an appliance or a fitting is under their responsibility, storage or transport conditions do not jeopardise its compliance with the essential requirements
    • make sure that the corrective measures necessary to bring that appliance or fitting into conformity, to withdraw it or recall it, if appropriate, are taken. Furthermore, where the appliance or the fitting presents a risk, distributors shall immediately inform the competent national authorities of the Member States in which they made the appliance or the fitting available on the market to that effect, giving details, in particular, of the non-compliance and of any corrective measures take