prEN 17127

Outdoor hydrogen refuelling points dispensing gaseous hydrogen and incorporating filling protocols

This document defines the minimum requirements to ensure the interoperability of hydrogen refuelling points, including refuelling protocols that dispense gaseous hydrogen to road vehicles (e.g. Fuel Cell Electric Vehicles) that comply with legislation applicable to such vehicles.
The safety and performance requirements for the entire hydrogen fuelling station, addressed in accordance with existing relevant European and national legislation, are not included in this document.
This document applies to hydrogen refuelling points dispensing gaseous hydrogen to vehicles compliant with UN R134 (Regulation No. 134), UN R134 or Regulation (EC) No 79/2009.
NOTE 1   Guidance on considerations for hydrogen fuelling stations is provided in ISO 19880 1:2020.
NOTE 2   Units used in this document follow SI (International System of Units).

Gasförmiger Wasserstoff - Betankungsanlagen - Teil 1: Allgemeine Anforderungen

Points de ravitaillement en hydrogène en extérieur distribuant de l'hydrogène gazeux et intégrant des protocoles de remplissage

Le présent document définit les exigences minimales permettant de garantir l’interopérabilité des points de ravitaillement en hydrogène intégrant les protocoles de remplissage qui distribuent de l’hydrogène gazeux pour les véhicules routiers (par exemple, les véhicules électriques à pile à combustible) qui sont conformes à la législation applicable à ces véhicules.
Les exigences de sécurité et de performances relatives à toute la station de remplissage d’hydrogène, traitées conformément à la législation européenne et nationale, ne sont pas incluses dans le présent document.
Le présent document s’applique aux points de ravitaillement en hydrogène distribuant de l’hydrogène gazeux aux véhicules conformes à l’UN ECE R134 ou au règlement (UE) n° 79/2009.
NOTE 1   Les recommandations relatives aux considérations concernant les stations de remplissage d’hydrogène sont fournies dans l’ISO 19880 1:2020.
NOTE 2   Les unités utilisées dans le présent document sont conformes au Système international d’unités (SI).

Zunanje polnilne postaje za plinasti vodik in postopki polnjenja

General Information

• Status: Not Published
• Publication Date: 14-Apr-2024
• ICS: 27.075 - Hydrogen technologies
• ICS: 75.200 - Petroleum products and natural gas handling equipment
• Technical Committee: CEN/TC 268 - Cryogenic vessels
• Drafting Committee: CEN/TC 268/WG 5 - Specific hydrogen technologies applications
• Current Stage: 4599 - Dispatch of FV draft to CMC - Finalization for Vote
• Start Date: 14-Jul-2023
• Due Date: 16-Jul-2023
• Completion Date: 14-Jul-2023
• Directive: 2014/94/EU - Directive 2014/94/EU of The European Parliament and of The Council of 22 October 2014 on the deployment of alternative fuels infrastructure
• Mandate: M/581 - Standardisation Request as regards communication exchange, electricity, and hydrogen supply for road, maritime transport and inland navigation in support of Directive 2014/94/EU and its planned revision under the ‘Fit for 55’package
• Ref Project: oSIST prEN 17127:2023 - Outdoor hydrogen refuelling points dispensing gaseous hydrogen and incorporating filling protocols

Relations

• Revises: EN 17127:2020 - Outdoor hydrogen refuelling points dispensing gaseous hydrogen and incorporating filling protocols
• Effective Date: 18-Jan-2023

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN 17127:2023
01-april-2023
Zunanje polnilne postaje za plinasti vodik in postopki polnjenja
Outdoor hydrogen refuelling points dispensing gaseous hydrogen and incorporating
filling protocols
Gasförmiger Wasserstoff - Betankungsanlagen - Teil 1: Allgemeine Anforderungen

Points de ravitaillement en hydrogène en extérieur distribuant de l'hydrogène gazeux et

intégrant des protocoles de remplissage
Ta slovenski standard je istoveten z: prEN 17127
ICS:
27.075 Tehnologija vodika Hydrogen technologies
75.200 Oprema za skladiščenje Petroleum products and
nafte, naftnih proizvodov in natural gas handling
zemeljskega plina equipment
oSIST prEN 17127:2023 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 17127:2023
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oSIST prEN 17127:2023
DRAFT
EUROPEAN STANDARD
prEN 17127
NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2023
ICS 27.075; 75.200 Will supersede EN 17127:2020
English Version
Outdoor hydrogen refuelling points dispensing gaseous
hydrogen and incorporating filling protocols

Points de ravitaillement en hydrogène en extérieur Gasförmiger Wasserstoff - Betankungsanlagen - Teil 1:

distribuant de l'hydrogène gazeux et intégrant des Allgemeine Anforderungen
protocoles de remplissage

This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee

CEN/TC 268.

If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations

which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other

language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC

Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,

Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and

United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are

aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without

notice and shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 17127:2023 E

worldwide for CEN national Members.
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Contents Page

European foreword ............................................................................................................................................. 3

Introduction .......................................................................................................................................................... 4

1 Scope .......................................................................................................................................................... 5

2 Normative references .......................................................................................................................... 5

3 Terms and definitions ......................................................................................................................... 5

4 Abbreviated terms ................................................................................................................................ 9

5 Characteristics and properties of hydrogen refuelling points ............................................. 9

5.1 General requirements ......................................................................................................................... 9

5.2 Fuel Quality ...........................................................................................................................................10

5.3 Dispenser process control ...............................................................................................................10

5.3.1 General requirements for the fuelling protocol.......................................................................10

5.3.2 Fuelling protocol process limits for vehicle dispensing systems ......................................11

5.3.3 Vehicle to station communications ..............................................................................................12

5.3.4 Dispenser Pressure Control Faults and over-pressure protection ...................................13

5.3.5 Dispenser temperature control faults .........................................................................................14

6 Inspection and validation of hydrogen refuelling points .....................................................14

6.1 Inspection prior putting into service and periodical inspection .......................................14

6.2 Minimum Site Acceptance Testing to ensure interoperability ...........................................14

Annex A (informative) Anticipated minimum vehicle characteristics .........................................16

Annex B (informative) Countermeasures for unsuitable hydrogen fuelling protocols ..........18

Bibliography ........................................................................................................................................................19

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European foreword

This document (prEN 17127:2023) has been prepared by Technical Committee CEN/TC 268 “Cryogenic

vessels and specific hydrogen technologies applications”, the secretariat of which is held by AFNOR.

This document is currently submitted to the CEN Enquiry.
This document will supersede EN 17127:2020.

This document has been prepared under a Standardization Request given to CEN by the European

Commission and the European Free Trade Association and supports essential requirements of EU

Directive(s) / Regulation(s).
The main changes compared to the previous edition are listed below:
— Improvement of the definitions;

— The general requirements of the characteristics and properties of hydrogen refuelling points have

been extended for higher flow rates needed for the refuelling of Heavy Duty Road vehicles;

— Communication is considered to improve the level of safety.
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Introduction

The European Commission in its standardization requests M/533 of March 12th, 2015 and M/581 of

March 24th 2022, aims to ensure that technical specifications for interoperability of refuelling points are

specified in European Standards compatible with the relevant International Standards. These

specifications aim to meet the European needs, be compatible and aligned as much as possible with

relevant International Standards and as far as possible with existing refuelling infrastructure already in

place and leave room to accommodate the adopted standard to local technical, analytical and regulatory

needs. The requested European Standards aim to be technologically and commercially neutral and based

on the know-how currently in the possession of the EU industry and of the public sector on a fair,

reasonable and non-discriminatory basis.

According to the legal requirements given in the Directive 2014/94/EU and the future EU Regulation

repealing the Directive 2014/94/EU” (AFIR) and M/533 and M/581, European Standards specifying only

the required specifications for ensuring the interoperability of refuelling points should be provided.

European standards and common requirements with respect to “interoperability” mean the capacity of

an infrastructure to supply energy (in this document, hydrogen) that is compatible with all vehicle

technologies and allows seamless EU-wide mobility and a clear definition of fuel pressure and

temperature levels and connector designs.

The European Standardization Organizations (ESOs) should adopt European Standards in accordance

with Article 10 of Regulation (EU) No 1025/2012 of the European Parliament and of the Council, and

those standards should be based on current International Standards or ongoing international

standardization work, where applicable.

Direction from the standardization request M/533 for European Standards for hydrogen supply are to

develop European Standards containing technical solutions for interoperability with technical

specifications in regard to Article 5 and point 2 of Annex II, in particular for:

a) outdoor hydrogen refuelling points dispensing gaseous hydrogen;
b) hydrogen purity dispensed by hydrogen refuelling points;
c) fuelling algorithms and equipment of hydrogen refuelling points;
d) connectors for vehicles for the refuelling of gaseous hydrogen.
This document specifies Items a) and c).
Item b) is covered by EN 17124 and Item d) by EN ISO 17268.

This document also addresses the standardization request M/581 for a European standard supporting

an interoperable infrastructure for hydrogen supply for road transport and containing technical

specifications with a unified solution for hydrogen refuelling points dispensing compressed (gaseous)

hydrogen for heavy duty vehicles.
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1 Scope

This document defines the minimum requirements to ensure the interoperability of hydrogen refuelling

points, including refuelling protocols that dispense gaseous hydrogen to road vehicles (e.g. Fuel Cell

Electric Vehicles) that comply with legislation applicable to such vehicles.

The safety and performance requirements for the entire hydrogen fuelling station, addressed in

accordance with existing relevant European and national legislation, are not included in this document.

This document applies to hydrogen refuelling points dispensing gaseous hydrogen to vehicles compliant

with UN R134 (Regulation No. 134), UN R134 or Regulation (EC) No 79/2009.

NOTE 1 Guidance on considerations for hydrogen fuelling stations is provided in ISO 19880-1:2020.

NOTE 2 Units used in this document follow SI (International System of Units).
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments) applies.

EN 17124, Hydrogen fuel - Product specification and quality assurance for hydrogen refuelling points

dispensing gaseous hydrogen - Proton exchange membrane (PEM) fuel cell applications for vehicles

EN ISO 17268, Gaseous hydrogen land vehicle refuelling connection devices (ISO/FDIS 17268)

3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

— IEC Electropedia: available at https://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp
3.1
compressed hydrogen storage system
CHSS

hydrogen storage on-board vehicle, as defined in the UN R134 (Regulation No. 134)

3.2
dispenser

equipment in the dispensing system, including the dispenser cabinet(s) and support structure, that is

physically located in the fuelling area

Note 1 to entry: The hydrogen dispenser typically includes, as a minimum, one or more fuelling assemblies

consisting of a nozzle, hose and break-away coupling, required temperature and pressure instrumentation, filters,

and the user interface to conduct vehicle fuelling.

Note 2 to entry: The manufacturer of the hydrogen dispenser can elect to include additional equipment in the

dispenser, including the possibility of all equipment in the dispensing system.
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3.3
dispenser cabinet

protective housing that encloses process piping and can also enclose measurement, control and ancillary

dispenser equipment
3.4
dispenser fuel pressure
pressure of the hydrogen gas supplied to the vehicle by the refuelling point

Note 1 to entry: See Annex A for discussion of pressure terminology and its application to dispensing systems.

3.5
dispenser fuel temperature
temperature of the hydrogen gas supplied to the vehicle by the refuelling point
3.6
dispensing system
hydrogen refuelling point

system downstream of the hydrogen supply system comprising all equipment necessary to carry out the

vehicle refuelling operation, through which the compressed hydrogen is supplied to the vehicle

[SOURCE: ISO 19880-1:2020]
3.7
hydrogen fuelling station

facility for the dispensing of compressed hydrogen vehicle fuel, often referred to as a hydrogen refuelling

station (HRS) or hydrogen filling station, including the supply of hydrogen compression, storage and

dispensing systems
3.8
hydrogen service level
HSL

pressure level in MPa used to characterize the hydrogen service of the dispenser based on the NWP rating

of the vehicle

Note 1 to entry: The numerical value of HSL also matches the number after the “H” in Pressure Class.

Note 2 to entry: See Annex A for application of pressure terminology to hydrogen dispenser systems and vehicles.

3.9
interoperability

capability of a hydrogen refuelling point to supply hydrogen at the fuelling station/vehicle interface that

is compatible with road vehicles and allows seamless EU-wide mobility through applying clear definitions

of connector designs, fuel quality, pressure levels, temperatures and other applicable considerations

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3.10
maximum allowable working pressure
MAWP

maximum pressure permissible in a vessel or system at the temperature specified for the pressure

Note 1 to entry: The maximum allowable working pressure can also be defined as the design pressure, the

maximum allowable operating pressure, the maximum permissible working pressure, or the maximum allowable

pressure for the rating of pressure vessels and equipment manufactured in accordance with national pressure

vessel codes.

Note 2 to entry: See Annex A for application of pressure terminology to hydrogen dispenser systems and vehicles.

3.11
maximum/minimum allowable temperature

values of the maximum/minimum temperatures at which safe and good functioning of the component is

ensured and for which it has been designed, as specified by the manufacturer
3.12
maximum developed pressure
MDP
highest pressure expected during fault management by the dispensing system

Note 1 to entry: Per the UN R134 (Regulation No. 134), the maximum developed pressure is 1,50 × NWP.

Note 2 to entry: The estimate of maximum developed pressure is based on “worst case” assumptions; the highest

possible setpoint for the pressure protection and maximum allowable values for setpoint accuracy and “lift” to open

the PSV for full relieving.
3.13
maximum fuelling pressure
MFP

maximum pressure applied to the vehicle high pressure hydrogen system during refuelling; 125 per cent

of the nominal working pressure
Note 1 to entry: See UN R134 (Regulation No. 134) Clause II-3.36.
Note 2 to entry: Also referred to as maximum fill pressure.
3.14
maximum operating pressure
MOP

highest pressure that is expected for a component or system during normal operation

Note 1 to entry: See Annex A for application of pressure terminology to hydrogen dispenser systems and vehicles.

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3.15
nominal working pressure
NWP
pressure of a-vehicle CHSS at 100% SOC at a gas temperature of 15 °C
Note 1 to entry: See UN R134 (Regulation No. 134) Clause II-3.37.
Note 2 to entry: For road vehicles, this is typically 35 MPa or 70 MPa.

Note 3 to entry: See Annex A for application of pressure terminology to hydrogen dispenser systems and vehicles.

3.16
pressure class

non-dimensional rating of components that indicates the components are designed to dispense hydrogen

to road vehicles at the required pressure and temperature

Note 1 to entry: The numbers following ‘H’ in the pressure class are numerically the same as the HSL, but the HSL

identifies only the level of the dispensing service, whereas the pressure class designation shows the component are

fully capable of meeting the pressure and temperature requirements for dispensing hydrogen at the indicated

service level.

Note 2 to entry: See Annex A for application of pressure terminology to hydrogen dispenser systems and vehicles.

3.17
pressure safety valve
PSV

pressure activated valve that opens at specified set point to protect a system from rupture and re-closes

when the pressure falls below the set point and which can reclose above the MOP
3.18
refuelling protocol

technical descriptions, instructions, or constructs that define how the dispensing of compressed gaseous

hydrogen to storage systems on vehicles should be conducted and that serves as the basis for defining

control strategies and algorithms for implementation in the basic process control of the dispensing

control system hardware and software

Note 1 to entry: Fuelling protocols can range from simple descriptions that can be performed in hardware to

complex programmable control functions using prescribed values, tables, and/or reduced-order models as well as

conventional process controls such as feed-forward/feedback and predictor/corrector control functions.

Note 2 to entry: A refuelling protocol can be also referred to as a refuelling algorithm.

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3.19
state of charge
SOC

density (or mass) ratio of hydrogen in the CHSS between the actual CHSS condition and the capacity at

NWP when the system is equilibrated at 15 °C

Note 1 to entry: SOC is expressed as a percentage and is computed based on the gas density according to Formula 1

below.
ρ PT,
( )
SOC % ×100 (1)
( )
ρ NWP,15 °C
( )

Note 2 to entry: The accuracy of the NIST formula has been quantified to be to within 0,01 % from 255 K to 1 000 K

with pressures to 120 MPa at the time of publishing of this document.
The hydrogen densities at the two major nominal working pressures are:
— density of H at 35 MPa and 15 °C = 24,0 g/l;
— density of H at 70 MPa and 15 °C = 40,2 g/l.

Note 3 to entry: The ρ(P,T) function for hydrogen is available from the National Institute of Standards and

Technology (NIST) at https://nvlpubs.nist.gov/nistpubs/jres/113/6/V113.N06.A05.pdf.

3.20
target pressure

dispenser fuel pressure that the hydrogen fuelling protocol targets for the end of refuelling

4 Abbreviated terms
H35 Indication for 35 MPa NWP hydrogen refuelling as defined in EN ISO 17268
H70 Indication for 70 MPa NWP hydrogen refuelling as defined in EN ISO 17268
5 Characteristics and properties of hydrogen refuelling points
5.1 General requirements

The hydrogen refuelling point shall be able to refuel hydrogen vehicles certified according to UN

Regulation 134, regulation (EU) 2019/2144 or EC 79/2009 for already approved vehicles without

compromising their specification limits.

NOTE 1 Assumptions made on the minimum characteristics of the hydrogen vehicle necessary to ensure

interoperability with the refuelling points defined in this document are outlined in Annex A.

Hydrogen refuelling points that would potentially be harmful to vehicles compliant with UN Regulation

134, regulation (EU) 2019/2144 or EC 79/2009 for already approved vehicles (for example, due to the

protocol used) should use countermeasures to prevent unsafe refuelling from occurring.

NOTE 2 Examples of countermeasures that can be employed to prevent vehicles refuelling at refuelling points

where the protocol could be unsafe for vehicles compliant with UN R134 or Regulation (EC) No 79/2009 are

provided in Annex B.

Refuelling points shall provide hydrogen at either H35 and/or H70 (relating to an NWP in the vehicle of

35 MPa and 70 MPa respectively) via appropriately rated components.
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The refuelling nozzle shall be compatible with vehicle hydrogen receptacles that comply with

EN ISO 17268.

Instructions for use of the hydrogen refuelling point by the general public shall be included on or in the

vicinity of each dispenser. The fuel (i.e. hydrogen) and pressure class shall be clearly indicated. Dispenser

operation instructions for dispensing hydrogen into a vehicle may be displayed as markings or as an

electronic display at the dispenser.
These instructions shall include prohibitions against:

— the use of adapters (e.g. 35 MPa vehicle refuelling from 70 MPa nozzle, or alternative fuel nozzles);

— the refuelling of cylinder systems (whether in a vehicle or not) that are incompatible with the fuelling

protocol employed at the refuelling point, see 5.3.

NOTE 3 EN 16942 includes information on labelling requirements for hydrogen refuelling points, and hydrogen

vehicles, in Europe.
5.2 Fuel Quality
The hydrogen quality at the nozzle shall meet the requirements of EN 17124.

To prevent hydrogen containing function-impairing impurities (i.e. particulates) that would affect the

high pressure hydrogen system of the vehicle, specifically the vehicle CHSS valves, hydrogen filters shall

be included as part of the dispenser. There shall be a filter with a capability to prevent particulates of a

maximum size of 5 µm with a minimum removal efficiency of 99 % under expected process conditions,

or alternatively a 5 µm filter. The filter shall be installed downstream of dispenser components which

could create particulates, such as a heat exchanger, flow controller, valves, etc. and be as close as possible

to the nozzle or hose breakaway device. This shall filter out the particulate concentration in the hydrogen

as per EN 17124.

All filters located at the nearest side to the nozzle shall be carefully selected by taking the robustness into

account (for example the durability limitations of powdered sintered metal filters).

EN ISO 4022, ISO 12500-1 and ISO 12500-3 provide recommended methodologies for the testing of filter

efficiencies.
5.3 Dispenser process control
5.3.1 General requirements for the fuelling protocol

In order to ensure that the refuelling is conducted within the fuelling protocol process limits for vehicle

compressed hydrogen storage systems, as defined in 5.3.2, hydrogen refuelling systems shall either:

— use an approved published fuelling protocol developed by a recognized standards development

organization (SDO), such as SAE J2601;

— use protocols that have followed a process of validation and been communicated to the

manufacturers of each vehicle that fuels at that refuelling point using that protocol and to regulatory

authorities when appropriate. Measures shall be taken to prevent the refuelling of vehicles at a

refuelling point where protocols have not been communicated to the manufacturer(s) of the vehicles

using that refuelling point.

NOTE Examples of countermeasures that can be employed to prevent vehicles fuelling at refuelling points

where the fuelling protocol has not been approved are provided in Annex B.
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The fuelling protocol shall ensure, directly or indirectly, that the maximum CHSS material temperature

does not exceed 85 °C throughout the refuelling.

The fuelling protocol shall consider the possible range of temperatures of the CHSS of the vehicle prior to

refuelling as well as the full range of ambient temperatures when establishing the refuelling rates, to

ensure that the storage system on the vehicle does not inadvertently experience an over-fill or over-

temperature condition.

If necessary, the fuelling protocol shall adjust the refuelling rate and target pressure based on measured

ambient and process conditions, such as dispensed hydrogen gas temperature and pressure, to ensure

that the process limits listed in 5.3.2 below are maintained for the vehicle. If these conditions cannot be

maintained within the limits, the refuelling shall cease.

The fuelling protocol should be appropriate for the range of vehicle tank capacities that are intended to

be refuelled.

Measures should be taken to ensure that sequential refuelling of the same vehicle does not lead to an

unsafe situation, for example using different fuelling protocols, at different fuel temperatures.

The dispensing system may either conduct the refuelling using communication with the vehicle as part

of the refuelling process (see 5.3.3) or conduct the fuelling protocol without communications with the

vehicle. The fuelling protocol may have provisions for both communication and non-communications

fuellings. At this point in time communication should be considered to improve the level of safety.

The fuelling protocol shall include a leak check of the fuel hose, hose breakaway device, nozzle and

connection to the vehicle before refuelling. The leak check shall be carried out while the vehicle is

connected. The refuelling shall be stopped in the event of leak detection above the acceptable limit.

5.3.2 Fuelling protocol process limits for vehicle dispensing systems

Hydrogen refuelling points shall be designed to fuel vehicles compliant with UN Regulation 134,

regulation (EU) 2019/2144 or EC 79/2009 for already approved vehicles (see Annex A for relevant limits

based on assumptions made about the vehicle being refuelled) by fulfilling the requirements of this

subclause. Refuelling points using fuelling protocols that could potentially be unsafe for such vehicles

shall incorporate appropriate countermeasures.

NOTE 1 Examples of countermeasures that can be employed to prevent vehicles refuelling at refuelling points

where the fuelling protocol could be unsafe for UN R134 or Regulation (EC) No 79/2009 vehicles are provided in

Annex B.

The refuelling of vehicles or equipment not compliant with the UN Regulation 134, regulation (EU)

2019/2144 or EC 79/2009 for already approved vehicles should be addressed by risk assessment and, if

necessary, the fuelling protocol process limits defined in this chapter should be revised accordingly.

The fuelling protocol shall ensure the following.

During the refuelling process, the refuelling point dispensing system shall meet the following fuelling

protocol limits, or terminate the refuelling within 5 s:
— ambient temperature no less than −40 °C and no greater than +50 °C;

— dispenser fuel pressure less than the maximum operating pressure (MOP), see 5.3.4;

NOTE 2 See 5.3.4 for over-pressure protection measures if a fault occurs.
— dispenser fuel temperature greater than −40 °C;

— the station shall limit the maximum flow rate according to the type of nozzle installed on the

dispensing system (excluding momentary excursions during the initial connection sequence - i.e.

connecting the nozzle to the receptacle prior to the start of refuelling and/or the pulse of hydrogen

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from the dispenser to the vehicle in order to equalize the station pressure with that of the vehicle to

carry out the pressure integrity check before refuelling and to establish the initial pressure).

— When not defined EN ISO 17268 the following maximum flow rate limits shall be used:

— 60g/s for H35 and H70 standard nozzles, unless a communication fuelling protocol is

incorporated that permits 90g/s and the nozzle design is suitable for 90g/s;
— 120g/s for H35HF (High Flow) nozzles;

— where communications are used, a communicated CHSS temperature less than 85 °C;

— a maximum of 10 pauses during refuelling where the fuel flow rate drops below 1 % of the maximum

flow rate limit (for example 0,6g/s where the limit is 60g/s for standard nozzles).

Additionally, the dispensing system shall also terminate the refuelling within 5 s if any of the following

events occur:

— where communications are used in case an Abort or Halt signal is received from the vehicle being

refuelled;
— any deviations from the fuelling protocol (see 5.3.1) arise;
— the flow rate, for the vehicle class, defined in this section is exceeded.

As part of the fuelling protocol, a quantity of hydrogen may be transferred to the vehicle to determine the

start pressure prior to the start of refuelling:

— the maximum hydrogen mass allowed to be transferred to the vehicle during this process should be

limited to 10 % of the lower total CHSS capacity accommodated by the fuelling protocol (for example

200g where the limit is 2kg for the refu
...