UAE Technical regulation  for FCV  
 Emirates Authority for Standardization & Metrology (ESMA)  
 
   
 
 
  
 
اللائحة الامارتية الخاصة بـ 
 
المتطلبات الفنية للمركبات التي تعمل بخلايا الهيدروجين 
Technical regulation on hydrogen and fuel cell vehicles  
 
 
 
 
 
 
 
دولة الإمارات العربية المتحدة 
UNITED AR AB EMIRATES  
 
 
© ESMAجميع حقوق الطبع محفوظة لهيئة الإمارات للمواصفات والمقاييس                            
 
ICS: 43 .020              
 
 
 
UAE Technical regulation  for FCV  
  
تقديم 
هيئة الإمارات للمواصفات والمقاييس هي الهيئة الجهة الاتحادية المسئولة عن أنشطة التقييس بالدولة ومن 
مهامها إعداد المواصفات القياسية والتي تتولى إعدادها لجان فنية متخصصة، أو فرق عمل فنية،   
 وقدددد قدددا  فريدددل العمدددل الم لددد  بإعدددداد مشدددرو  هددد   اللائحدددة وتدددم تعميمدددك علدددى كافدددة الجهدددات المعنيدددة 
فددي دا ددل و ددارل الدولددة وتمدد  مناقشددة جميدد  الملاحظددات والآراء الددوارد  وصدديا ة المشددرو  
بالصور  النهائية وتم اعتماد  وإصدار  للتطبيل بش ل إلزامية بقرار من مجلس الوزراء. 
 
 
Foreword  
Emirates Authority for Standardization &  Metrology (ESMA) is the national 
Standard body, one of its main functions is preparing and issuing UAE national 
standards  through technical committees (TCs) or working group . 
Working group for Vehicles prepared draft of this standard and circulated to 
all partnership inside and outside UAE. Received comments had been 
considering in the final draft of standard.  
 This technical  regulation is approved and issued as compulsory by UAE 
Ministerial Cabinet.  
 
 
 
 UAE Technical regulation  for FCV  
 Technical regulation on hydrogen and fuel cell vehicles  
  
 1.    Scope  
 This regulation applies to all hydrogen fuelled vehicles of Category 1 -1 and  
1-2, with a gr oss vehicle mass (GVM) of 4,536 kilograms or less . 
 2.   Definitions  
 For the purpose of this regulation, the following definitions shall apply:  
2.1. "Active driving possible mode"  is the vehicle mode when application of pressure to the accelerator pedal (or 
activation of an equivalent control) or release of the brake system causes the electric power train to move the 
vehicle  
 
3.2. "Automatic disconnect"  is a device that, when triggered, conductively separates the electrical energy sources 
from the rest of  the high voltage circuit of the electrical power train.  
3.3. "Burst -disc"  is the non -reclosing operating part of a pressure relief device which, when installed in the device, 
is designed to burst at a predetermined pressure to permit the discharge of comp ressed hydrogen.  
3.4. "Check valve"  is a non -return valve that prevents reverse flow in the vehicle fuel line.  
3.5. "Concentration of hydrogen" is the percentage of the hydrogen moles  (or molecules) within the mixture of 
hydrogen and air (Equivalent to the  partial volume of hydrogen gas).  
3. ANNEX 1.  "Container " (for hydrogen storage) is the component within the hydrogen storage system that stores 
the primary volume of hydrogen fuel.  
3.7. "Conductive connection"  is the connection using contactors to an extern al power supply when the rechargeable 
energy storage system (REESS) is charged.  
3.8. "Coupling system" for charging the rechargeable energy storage system  (REESS) is the electrical circuit used 
for charging the REESS from an external electric power supply including the vehicle inlet.  
3.9. "Date of removal from service" is the date (month and year) specified for removal from service.  
3.10.  "Date of manufacture"  (of a compressed hydrogen container) is the date (month and year) of the proof pressure 
test carri ed out during manufacture.  
3.11.  "Direct contact"  indicates the contact of persons with high voltage live parts.  
3.12.    "Enclosed or semi -enclosed spaces"  indicates the special volumes within the vehicle (or the vehicle outline 
across openings) that are external to the hydrogen system (storage system, fuel cell system and fuel flow 
management system) and its housings (if any) where hydrogen may accumulate (and thereby pose a hazard), 
as it may occur in the passenger compartment, luggage compartment, cargo  compartment and space under the 
hood.  
3.13.  "Enclosure"  is the part enclosing the internal units and providing protection against any direct contact.  
3.14.  "Electric energy conversion system" is a system (e.g. fuel cell) that generates and provides electr ical power 
for vehicle propulsion.  
3.15.  "Electric power train"  is the electrical circuit which may include the traction motor(s), and may also include 
the REESS, the electrical power conversion system, the electronic converters, the traction motors, the 
associated wiring harness and connectors and the coupling system for charging the REESS.  UAE Technical regulation  for FCV  
 3.1 ANNEX 1.  "Electrical chassis"  is a set of conductive parts electrically linked together, whose electrical 
potential is taken as reference.  
3.17.  "Electrical circuit"  is an assembly of connected high voltage live parts that is designed to be electrically 
energized in normal operation.  
3.18.  "Electrical isolation"  is the electrical resistance between a vehicle high voltage bus source and any vehicle 
conductive structure.  
3.19.  "Electrical protection barrier"  is the part providing protection against direct contact with live parts from any 
direction of access.  
3.20.  "Electronic converter"  is a device capable of controlling and/or converting electric power for propulsion.  
3.21. "Exhaust point of discharge"  is the geometric centre of the area where fuel cell purged gas is discharged from 
the vehicle.  
3.22.  "Exposed conductive part"  is the conductive part that can be touched under the provisions of the IPXXB 
protection degree a nd becomes electrically energized under isolation failure conditions. This includes parts 
under a cover that can be removed without using tools.  
3.23.  "External electric power supply"  is an alternating current (AC) or direct current (DC) that provides elec tric 
power outside of the vehicle.  
3.24.  "Fuel cell system" is a system containing the fuel cell stack(s), air processing system, fuel flow control system, 
exhaust system, thermal management system and water management system.  
3.25.  "Fuelling receptacle"  is the equipment to which a fuelling station nozzle attaches to the vehicle and through 
which fuel is transferred to the vehicle. The fuelling receptacle is used as an alternative to a fuelling port.  
3.2 ANNEX 1.  "High voltage" is the classification of an ele ctric component or circuit, if its maximum working 
voltage is greater than 60 V and less than or equal to 1500  V of direct current  (DC), or greater than 30 V and 
less than or equal to 1000 V of alternating current (AC).  
3.27.  "High Voltage Bus"  is the elec trical circuit, including the coupling system, for charging the REESS that 
operates on high voltage.  
3.28.  "Hydrogen -fuelled vehicle"  indicates any motor vehicle that uses compressed gaseous or liquefied hydrogen 
as a fuel to propel the vehicle, including fuel cell and internal combustion engine vehicles. Hydrogen fuel for 
passenger vehicles is specified in ISO 14687 -2 and SAE J2719.  
3.29.  "Hydrogen storage system"  indicates a pressurized container, pressure relief devices (PRDs) and shut off 
device that is olate the stored hydrogen from the remainder of the fuel system and the environment.  
3.30.  "Indirect contact"  is the contact of persons with exposed conductive parts.  
3.31.  "Live parts"  is the conductive part intended to be electrically energized in normal  use. 
3.32.  "Luggage compartment"  is the space in the vehicle for luggage accommodation, bounded by the roof, hood, 
floor, side walls, as well as by the electrical barrier and enclosure provided for protecting the power train from 
direct contact with live parts, being separated from the passenger compartment by the front bulkhead or the 
rear bulkhead.  
3.33.  "Liquefied hydrogen storage system"  indicates liquefied hydrogen storage container(s) PRDs, shut off device, 
a boil -off system and the interconnection  piping (if any) and fittings between the above components.  
3.34.  "Lower flammability limit  (LFL)"  is the lowest concentration of fuel at which a gaseous fuel mixture is 
flammable at normal temperature and pressure.  The lower flammability limit for hydrogen gas in air is 
4 per cent by volume (   83 of the Preamble ). 
3.35.  "Maximum allowable working pressure  (MAWP) " is the highest gauge pressure to which a pressure container 
or storage system is permitted to operate under normal operating conditions.  
3.3 ANNEX 1.  "Maximum fuelling pressure  (MFP) " is the maximum pressure applied to compressed system during 
fuelling. The maximum fuelling pressure is 125 per cent of the Nominal Working Pressure.  UAE Technical regulation  for FCV  
 3.37.  "Nominal working pressure  (NWP) " is the gauge pressure that charac terizes typical operation of a system. For 
compressed hydrogen gas containers, NWP is the settled pressure of compressed gas in fully fuelled container 
or storage system at a uniform temperature of 15  °C.  
3.38.  "On-board isolation resistance monitoring sy stem"  is the device that monitors isolation resistance between 
the high voltage buses and the electrical chassis.  
3.39.  "Open type traction battery"  is a type of battery requiring liquid and generating hydrogen gas that is released 
into the atmosphere.  
3.40. "Passenger compartment (for electric safety assessment)"  is the space for occupant accommodation, bounded 
by the roof, floor, side walls, doors, outside glazing, front bulkhead and rear bulkhead - or rear gate -, as well 
as by the electrical barriers a nd enclosures provided for protecting the occupants from direct contact with live 
parts.  
3.41.  "Pressure relief device  (PRD) " is a device that, when activated under specified performance conditions, is 
used to release hydrogen from a pressurized system and  thereby prevent failure of the system.  
3.42.  "Pressure relief valve"  is a pressure relief device that opens at a preset pressure level and can re -close.  
3.43.  "Protection degree IPXXB " indicates protection from contact with high voltage live parts provide d by either 
an electrical barrier  or an enclosure; it is tested using a Jointed Test Finger (IPXXB), as described in paragraph  
ANNEX 1. 3.3. 
3.44.  "Protection degree IPXXD " indicates protection from contact with high voltage live parts provided by either 
an electrical barrier  or an enclosure and tested using a Test Wire (IPXXD), as described in paragraph  ANNEX 
1.3.3. 
3.45.  "Rechargeable energy storage system  (REESS)" is the rechargeable energy storage system that provides 
electric energy for electrical propul sion.  
3.4 ANNEX 1.  "Rupture  and burst"  both mean to come apart suddenly and violently, break open or fly into pieces 
due to the force of internal pressure.  
3.47.  "Service disconnect"  is the device for deactivation of an electrical circuit when conducting che cks and services 
of the REESS, fuel cell stack, etc.  
3.48.  "Service life"  (of a compressed hydrogen container) indicates the time frame during which service (usage) is 
authorized.  
3.49.  "Shut-off valve"  is a valve between the storage container and the vehi cle fuel system that can be automatically 
activated; this valve defaults to "closed" position when not connected to a power source.  
3.50.  "Single failure"  is a failure caused by a single event, including any consequential failures resulting from this 
failure. 
3.51.  "Solid insulator"  is the insulating coating of wiring harnesses provided in order to cover and prevent the high 
voltage live parts from any direct contact. This includes covers for insulating the high voltage live parts of 
connectors and varnish or paint for the purpose of insulation.  
3.52.  "Thermally -activated pressure relief device  (TPRD) " is a non - reclosing PRD that is activated by temperature 
to open and release hydrogen gas.  
3.53.  "Type approval"  indicates a certification of a recognised bod y stating that prototype or pre -production samples 
of a specific vehicle, vehicle system or vehicle system component meet the relevant specified performance 
standards, and that the final production versions also comply, as long as conformity of production is confirmed.  
3.54.  "Vehicle fuel system"  is an assembly of components used to store or supply hydrogen fuel to a fuel cell (FC) 
or internal combustion engine (ICE).  
3.55.  "Working voltage"  is the highest value of an electrical circuit voltage root mean sq uare (rms), specified by the 
manufacturer or determined by measurement, which may occur between any conductive parts in open circuit 
conditions or under normal operating condition. If the electrical circuit is divided by galvanic isolation, the 
working vol tage is defined for each divided circuit, respectively.  UAE Technical regulation  for FCV  
   4.  Applicability of requirements  
4.1. The requirements of paragraph 5. ( Using  test conditions and procedures in paragraph  ANNEX 1. ) Apply  to 
all compressed hydrogen fuelled vehicles.  
4.2. Crash test s (frontal, side, rear and rollover) for compliance with section 5.2.2. should be according GSO 42 . 
4.3. The requirements of paragraph 5.3. Apply  to all hydrogen -fuelled vehicles using high voltage.  
  5.   Performance requirements  
5.1. Compressed hydrogen storage system  
 This section specifies the requirements for the integrity of the compressed hydrogen storage system. The 
hydrogen storage system consists of the high pressure storage container and primary closure devices for 
openings into the high pressure  storage container. Figure 1 shows a typical compressed hydrogen storage 
system  
Figure 1  
Typical compressed hydrogen storage system  
 
 
 
 
 
 
 
 
 
 
 
 
All new compressed hydrogen storage systems produced for on -road vehicle service shall have a NWP of 70 MPa or  
less and a service life of 15 years or less, and be capable of satisfying the requirements of paragraph 5.1.  
The hydrogen storage system shall meet the performance test requirements specified in this paragraph.  
The test elements within these performance requirements are summarized in Table 1. The corresponding test 
procedures are specified in paragraph  ANNEX 1.  
Table 1  
Overview of performance qualification test requirements  
5.1.1. Verification tests for baseline metrics  
5.1.1.1. Baseline initial burst pres sure 
5.1.1.2. Baseline initial pressure cycle life  
5.1.2. Verification test for performance durability (sequential hydraulic tests)  
5.1.2.1. Proof pressure test  
5.1.2.2. Drop (impact) test  
5.1.2.3. Surface damage  
5.1.2.4. Chemical exposure and ambient tem perature pressure cycling tests  
5.1.2.5. High temperature static pressure test  
5.1.2.  ANNEX 1.  Extreme temperature pressure cycling  
Containment
VesselShut -off
ValveCheck
ValveTPRD
vent
Storage
ContainerContainment
VesselShut -off
ValveCheck
ValveTPRD
vent
Storage
ContainerUAE Technical regulation  for FCV  
 5.1.1. Verification tests for baseline metrics  
5.1.1.1. Baseline initial burst pres sure 
5.1.1.2. Baseline initial pressure cycle life  
5.1.2.7. Residual proof pressure test  
5.1.2.8. Residual strength Burst Test  
5.1.3. Verification test for expected on -road per formance (sequential pneumatic tests)  
5.1.3.1. Proof pressure test  
5.1.3.2. Ambient and extreme temperature gas pressure cycling test (pneumatic)  
5.1.3.3. Extreme temperature static gas pressure leak/permeation test (pneumatic)  
5.1.3.4. Residual proof pres sure test  
5.1.3.5. Residual strength burst test (hydraulic)  
5.1.4. Verification test for service terminating performance in fire  
5.1.5. Verification test for closure durability   
5.1.1.   Verification tests for baseline metrics  
5.1.1.1.  Baseline initial burst pressure  
 Three (3) new containers randomly selected from the design qualification batch of at least 10 containers, are 
hydraulically pressurized until burst (    ANNEX 1. 2.2.1. test procedure). The manufacturer shall supply 
documentation (measurements and statistical analyses) that establish the midpoint burst pressure of new 
storage containers, BP O. 
  All containers tested shall have a burst pressure within ±10 per cent of BP O and greater than or equal to a 
minimum BPmin of 225 per cent NWP .  
            In addition, containers having glass -fibre composite as a primary constituent to have a minimum burst pressure 
greater than 350 per cent NWP.  
5.1.1.2.  Baseline initial pressure cycle life  
  Three (3) new containers randomly selected from the design qua lification batch are hydraulically pressure 
cycled at 20( ±5)°C to 125 per cent NWP without rupture for 22,000 cycles or until a leak occurs (    ANNEX 
1.2.2.2. test procedure). Leakage shall not occur within a number of Cycles, where the number of Cycles is 
set individually by each Contracting Party at 5,500, 7,500 or 11,000 cycles for a 15 -year service life.  
5.1.2.   Verification tests for performance durability (Hydraulic sequential tests)  
  If all three pressure cycle life measurements made in   5.1.1.2. are  greater than 11,000 cycles, or if they are 
all within ±25 per cent of each other, then only one (1) container is tested in   5.1.2. Otherwise, three (3) 
containers are tested in   5.1.2.  
  A hydrogen storage container shall not leak during the following s equence of tests, which are applied in 
series to a single system and which are illustrated in Figure 2. At least one system randomly selected from the 
design qualification batch shall be tested to demonstrate the performance capability. Specifics of applic able 
test procedures for the hydrogen storage system are provided in    ANNEX 1. 2.3. 
 
 
 
 
 
Figure 2  
Verification test for performance durability (hydraulic)  UAE Technical regulation  for FCV  
  
 
5.1.2.1.  Proof pressure test  
A storage container is pressurized to 150 per cent NWP and held for 3 0 sec (    ANNEX 1. 2.3.1. test procedure). A 
storage container that has undergone a proof pressure test in manufacture is exempt from this test.  
5.1.2.2.  Drop (impact) test  
The storage container is dropped at several impact angles (    ANNEX 1. 2.3.2. test proced ure). 
5.1.2.3.  Surface damage test  
The storage container is subjected to surface damage (    ANNEX 1. 2.3.3. test procedure).  
5.1.2.4.  Chemical exposure and ambient -temperature pressure cycling test  
The storage container is exposed to chemicals found in the on-road environment and pressure cycled to 125 per cent 
NWP at 20° ( ±5)°C for 60  per cent number of Cycles pressure cycles (    ANNEX 1. 2.3.4.  test procedure ). 
Chemical exposure is discontinued before the last 10  cycles, which are conducted to 150 per cent  NWP.  
5.1.2.5.  High temperature static pressure test.  
The storage container is pressurized to 125 per cent NWP at 85°C for 1,000  hr (   ANNEX 1. 2.3.5. test procedure).  
5.1.2.  ANNEX 1.  Extreme temperature pressure cycling.  
The storage container is pressure cycl ed at   -40°C to 80 per cent NWP for 20 per cent number of Cycles and at  
+85°C and 95 per cent relative humidity to 125 per cent NWP for 20 per cent number of Cycles (    ANNEX 
1.2.2.2. test procedure).  
5.1.2.7.  Hydraulic residual pressure test. The storage  container is pressurized to 180  per cent NWP and held 4 minutes 
without burst (    ANNEX 1. 2.3.1. test procedure).  
5.1.2.8.  Residual burst strength test  
The storage container undergoes a hydraulic burst test to verify that the burst pressure is at least 80 per cent of the 
baseline initial burst pressure (BP O) determined in   5.1.1.1. (    ANNEX 1. 2.2.1. test procedure).  
5.1.3.   Verification test for expected on -road performance (Pneumatic sequential tests)  
A hydrogen storage system shall not leak during the fol lowing sequence of tests, which are illustrated in Figure 3. 
Specifics of applicable test procedures for the hydrogen storage system are provided in paragraph  ANNEX 
1. 
+85C, 95%RHPressure 
DamageDroptimeBPO<20%
Residual
StrengthChemicals
48 hr60% #Cycles
15C-25Cchemical
exposure 150% NWPburst
125%NWP180%NWP
(4min)
1000 hr
+85C
20% #Cycles
-40C20% #Cycles 10
cycles
15-25CProof Pressure80%NWPUAE Technical regulation  for FCV  
 Figure 3  
Verification test for expected on -road performance (pneumatic/hydraulic)  
 
5.1.3 .1. Proof pressure test  
A system is pressurized to 150 per cent NWP for 30 seconds (    ANNEX 1. 2.3.1. test procedure). A storage 
container that has undergone a proof pressure test in manufacture is exempt from this test.  
5.1.3.2.  Ambient and extreme temperat ure gas pressure cycling test  
The system is pressure cycled using hydrogen gas for 500 cycles (    ANNEX 1. 2.4.1. test procedure).  
(a) The pressure cycles are divided into two groups: Half of the cycles (250) are performed before exposure to 
static pressure (   5.1.3.3.) and the remaining half of the cycles (250) are performed after the initial exposure 
to static pressure (   5.1.3.3.) as illustrated in Figure 3;  
(b) The first group of pressure cycling, 25 cycles are performed to 80 per cent NWP at  -40 °C, the n 25 cycles 
to 125 per cent NWP at  + 50 °C and 95 per cent relative humidity, and the remaining 200  cycles to 125 per 
cent NWP at 20 ( ±5)°C; 
 The second group of pressure cycling, 25 cycles are performed to 125  per cent NWP at  + 50 °C and 95  per 
cent r elative humidity, then 25 cycles to 80 per cent NWP at  -40 °C, and the remaining 200  cycles to 125 
per cent NWP at 20(±5)°C .  
(c) The hydrogen gas fuel temperature is  - 40 °C;  
(d) During the first group of 250 pressure cycles, five cycles are performed  with fuel having a temperature of  
+ 20(±5)°C  after temperature equilibration of the system at  - 40°C; five cycles are performed with fuel 
having a temperature of   - 40°C; and five cycles are performed with fuel having a temperature of  - 40°C 
after te mperature equilibration of the system at   50°C and 95 per cent relative humidity;  
(e) Fifty pressure cycles are performed using a de -fuelling rate greater than or equal to the maintenance de -fuelling 
rate. 
5.1.3.3.  Extreme temperature static pressure le ak/permeation test.  
(a) The test is performed after each group of 250 pneumatic pressure cycles in paragraph 5.1.3.2.;  
(b) The maximum allowable hydrogen discharge from the compressed hydrogen storage system is 46 mL/h/L 
water capacity of the storage syste m. (   ANNEX 1. 2.4.2. Test procedure ); 
cbProof  Pressure 5% cy  -40Ca
5% cy  +50Cb 
40%cy 15 -25Cc150%
NWP+55oC +55oC    aPressure 
timeBurstBPO<20%
Leak / Permeation
>30 hrs
a  Fuel/defuel cycles @ -40oC with initial system equilibration @ -40oC, 5 cycles with +20oC fuel; 5 cycles with < -35oC fuel
b  Fuel/defuel cycles @+50oC with initial system equilibration @+50oC, 5 cycles with < -35oC fuel
c  Fuel/defuel cycles @15 -25oC with service (maintenance) defuel rate, 50 cycles5% cy +50C
5% cy  -40C
40%cy 15 -25C
Leak / Permeation
>30 hrs180%NWP4 min
125%NWP
115%NWP
80%NWP
a bUAE Technical regulation  for FCV  
 (c) If the measured permeation rate is greater than 0.005 mg/sec (3.6  Nml/min), a localized leak test is performed 
to ensure no point of localized external leakage is greater than 0.005  mg/sec (3.6  Nml/min) (    ANNEX 1. 2.4.3. 
test procedure).  
5.1.3.4.  Residual proof pressure test (hydraulic)  
            The storage container is pressurized to 180 per cent NWP and held 4 minutes without burst (    ANNEX 1. 2.3.1. 
test procedure).  
5.1.3.5.  Residual strength burst test (hydraulic ) 
The storage container undergoes a hydraulic burst to verify that the burst pressure is within 20 per cent of the 
baseline burst pressure determined in   5.1.1.1. (    ANNEX 1. 2.2.1. test procedure).  
5.1.4.   Verification test for service terminating performa nce in fire  
  This section describes the fire test with compressed hydrogen as the test gas.  
  A hydrogen storage system is pressurized to NWP and exposed to fire (    ANNEX 1. 2.5.1. test procedure). 
A temperature -activated pressure relief device  shall rele ase the contained gases in a controlled 
manner without rupture.  
5.1.5.   Verification test for performance durability of primary closures  
  Manufacturers shall maintain records that confirm that closures that isolate the high pressure hydrogen 
storage syste m (the TPRD(s), check valve(s) and shut -off valve(s) shown in Figure 1) comply with the 
requirements described in the remainder of this Section.  
  The entire storage system does not have to be re -qualified (   5.1.) if these closure components (components 
in Figure 1 excluding the storage container) are exchanged for equivalent closure components having 
comparable function, fittings, materials, strength and dimensions, and qualified for performance using the 
same qualification tests as the original component s. However, a change in TPRD hardware, its position of 
installation or venting lines requires re -qualification with fire testing according to   5.1.4.  
5.1.5.1.  TPRD qualification requirements  
  Design qualification testing shall be conducted on finished pr essure relief devices, which  are representative 
of normal production. The TPRD shall meet the following performance qualification requirements:  
  (a) Pressure cycling test (    ANNEX 1. 2. ANNEX 1. 1.1.);  
  (b) Accelerated life test (    ANNEX 1. 2. ANNEX 1. 1.2.);  
  (c) Temperature cycling test (    ANNEX 1. 2. ANNEX 1. 1.3.);  
  (d) Salt corrosion resistance test (    ANNEX 1. 2. ANNEX 1. 1.4.);  
  (e) Vehicle environment test (    ANNEX 1. 2. ANNEX 1. 1.5.);  
  (f) Stress corrosion cracking test (    ANNEX 1. 2. ANNEX 1. 1. ANNEX 1. ); 
  (g) Drop and vibration test (    ANNEX 1. 2. ANNEX 1. 1.7.);  
  (h) Leak test (    ANNEX 1. 2. ANNEX 1. 1.8.);  
  (i) Bench top activation test (    ANNEX 1. 2. ANNEX 1. 1.9.);  
  (j) Flow rate test (    ANNEX 1. 2. ANNEX  1.1.10.).  
5.1.5.2.  Check valve and automatic shut -off valve qualification on requirements  
  Design qualification testing shall be conducted on finished check valves and shut -off valves which are 
representative of normal production. The valve units shall meet the following performance qualification 
requirements:  
  (a) Hydrostatic st rength test (    ANNEX 1. 2. ANNEX 1. 2.1.);  
  (b) Leak test (    ANNEX 1. 2. ANNEX 1. 2.2.);  UAE Technical regulation  for FCV  
   (c) Extreme temperature pressure cycling test (    ANNEX 1. 2. ANNEX 1. 2.3.);  
  (d) Salt corrosion resistance test (    ANNEX 1. 2. ANNEX 1. 2.4.); 
  (e) Vehicle environment test (    ANNEX 1. 2. ANNEX 1. 2.5.);  
  (f) Atmospheric exposure test (    ANNEX 1. 2. ANNEX 1. 2. ANNEX 1. ); 
  (g) Electrical tests (    ANNEX 1. 2. ANNEX 1. 2.7.);  
  (h) Vibration test (    ANNEX 1. 2. ANNEX 1. 2.8.);  
  (i) Stress corrosion cracking test (    ANNEX 1. 2. ANNEX 1. 2.9.);  
  (j) Pre-cooled  hydrogen exposure test (    ANNEX 1. 2. ANNEX 1. 2.10.).  
5.1. ANNEX 1.   Labelling  
  A label shall be permanently  affixed on each container with at least the following information: name of the 
manufacturer, serial number, date of manufacture, NWP, type of fuel, an d date of removal from service. Each 
container shall also be marked with the number of cycles used in the testing programme as per   5.1.1.2. Any 
label affixed to the container in compliance with this section shall remain in place and be legible for the 
duration of the manufacturer’s recommended service life for the container.  
  Date of removal from service shall not be more than 15 years after the date of manufacture.  
 
5.2.  Vehicle fuel system  
This section specifies requirements for the integrity of the h ydrogen fuel delivery system, which includes the hydrogen 
storage system, piping, joints, and components in which hydrogen is present.  
5.2.1.   In-use fuel system integrity  
5.2.1.1.  Fuelling receptacle requirements  
5.2.1.1.1.  A compressed hydrogen fuelling receptacle shall prevent reverse flow to the atmosphere. Test 
procedure is visual inspection.  
5.2.1.1.2.  Fuelling receptacle label A label shall be affixed close to the fuelling receptacle; for instance inside 
a refilling hatch, showing the following infor mation: fuel type, NWP, date of removal from service of 
containers.  
5.2.1.1.3.  The fuelling  receptacle shall be mounted on the vehicle to ensure positive locking of the fuelling 
nozzle.  The receptacle shall be protected from tampering and the ingress of di rt and water (e.g. installed in a 
compartment which can be locked ). Test procedure is by visual inspection.  
5.2.1.1.4.  The fuelling  receptacle shall not be mounted within the external energy absorbing elements of the 
vehicle (e.g. bumper) and shall not be installed in the passenger compartment, luggage compartment and other 
places where hydrogen gas could accumulate and  where  ventilation is not sufficient. Test procedure is by 
visual inspection.  
5.2.1.2.  Over -pressure protection for the low pressure system (   ANNEX 1. 1. ANNEX 1.  test procedure)  
  The hydrogen system downstream of a pressure regulator shall be protected against overpressure due to the 
possible failure of the pressure regulator. The set pressure of the overpressure protection device shall be lowe r 
than or equal to the maximum allowable working pressure for the appropriate section of the hydrogen system.  
5.2.1.3.  Hydrogen discharge systems  
5.2.1.3.1. Pressure relief systems (    ANNEX 1. 1. ANNEX 1.  test procedure)  
(a) Storage system TPRDs. The outlet of  the vent line, if present, for hydrogen gas discharge from TPRD(s) of 
the storage system shall be protected by a cap;  
(b) Storage system TPRDs. The hydrogen gas discharge from TPRD(s) of the storage system shall not be directed:  UAE Technical regulation  for FCV  
  (i) Into enclosed or semi -enclosed spaces;  
(ii) Into or towards any vehicle wheel housing;  
(iii) Towards hydrogen gas containers;  
(iv) Forward from the vehicle, or horizontally (parallel to road) from the back or sides of the vehicle.  
(c) Other pressure relief devices (such as a b urst disk) may be used outside the hydrogen storage system. The 
hydrogen gas discharge from other pressure relief devices shall not be directed:  
(i) Towards exposed electrical terminals, exposed electrical switches or other ignition sources;  
(ii) Into or t owards the vehicle passenger or cargo compartments;  
(iii) Into or towards any vehicle wheel housing;  
(iv) Towards hydrogen gas containers.  
5.2.1.3.2.  Vehicle Exhaust System (  ANNEX 1. 1.4. test procedure)  
At the vehicle exhaust system’s point of discharge, t he hydrogen concentration level shall:  
(a) Not exceed 4 per cent average by volume during any moving three -second time interval during normal 
operation including start -up and shutdown;  
(b) And not exceed 8 per cent at any time (  ANNEX 1. 1.4. test procedure) . 
5.2.1.4.  Protection against flammable conditions: single failure conditions  
5.2.1.4.1.  Hydrogen leakage and/or permeation from the hydrogen storage system shall not directly vent into the 
passenger, luggage, or cargo compartments, or to any enclosed or s emi-enclosed spaces within the vehicle,  
that contains unprotected ignition sources.  
5.2.1.4.2.  Any single failure downstream of the main hydrogen shut off valve shall not result in any level of a 
hydrogen concentration in anywhere in the passenger compartm ent according to test procedure    ANNEX 
1.1.3.2.  
5.2.1.4.3.  If, during operation, a single failure results in a hydrogen concentration exceeding 2 ± 1.0 per cent 
by volume in air in the enclosed or semi -enclosed spaces of the vehicle, then a warning shall b e provided (   
5.2.1.  ANNEX 1. ). If the hydrogen concentration exceeds 3 ± 1.0 per cent by volume in the air in the enclosed 
or semi -enclosed spaces of the vehicle, the main shutoff valve shall be closed to isolate the storage system. (    
ANNEX 1. 1.3. test proc edure).  
5.2.1.5.  Fuel system leakage  
 The hydrogen fuelling line and the hydrogen system(s) downstream of the  main shut off valve(s) shall 
not leak. Compliance shall be verified at NWP (    ANNEX 1. 1.5. test procedure).  
5.2.1.  ANNEX 1.  Tell-tale signal warning to driver  
  The warning shall be given by a visual signal or display text with the following properties:  
(a) Visible to the driver while in the driver's designated seating position with the driver's seat belt fastened;  
(b) Yellow in colour if the detection  system malfunctions and shall be red in compliance with section   5.2.1.4.3;  
(c) When illuminated, shall be visible to the driver under both daylight and night time driving conditions;  
(d) Remains illuminated when 2  ± 1.0 per cent concentration or detecti on malfunction) exists and the ignition 
locking system is in the "On" ("Run") position or the propulsion system is activated.  
5.2.2.   Post-crash fuel system integrity  
5.2.2.1.  Fuel leakage limit  
The volumetric flow of hydrogen gas leakage shall not exceed an average of 118 NL per minute for 60 minutes after 
the crash (    ANNEX 1. 1.1. test procedures).  
5.2.2.2.  Concentration limit in enclosed spaces    UAE Technical regulation  for FCV  
 Hydrogen gas leakage shall not result in a hydrogen concentration in the air greater than 3  ± 1.0 per cent ] by volume 
in the passenger, luggage and cargo compartments (    ANNEX 1. 1.2. test procedures).  The requirement is 
satisfied if it is confirmed that the shut -off valve of the storage system has closed within 5  seconds of the crash 
and no leakage from the storage  system.  
5.2.2.3.  Container Displacement  
The storage container(s) shall remain attached to the vehicle at a minimum of one attachment point.  
 
5.3.  Electrical safety  
5.3.1.   Electrical Safety requirements - in-use 
5.3.1.1.  General  
Paragraph 5.3.1. appli es to the electric power train of fuel cell vehicles equipped with one or more traction motor(s) 
operated by electric power and not permanently connected to the grid, as well as their high voltage components 
and systems which are conductively connected to the high voltage bus of the electric power train.  
5.3.1.2.  Requirements for protection against electric shock  
5.3.1.2.1.  Protection against electric shock  
These electrical safety requirements apply to high voltage buses under conditions where they are not connected to 
external high voltage power supplies.  
5.3.1.2.2.  Protection against direct contact  
The protection against direct contact with live parts shall comply with paragraphs 5.3.1.2.2.1. and 5.3.1.2.2.2. These 
protections (solid insulator, electrical protection barrier, enclosure, etc.) shall not be opened, disassembled or 
removed without the use of tools.  
5.3.1.2.2.1.   For protection of live parts inside the passenger compartment or luggage compartment, the 
protection degree IPXXD shall be provided.  
5.3.1.2.2.2.  For protection of live parts in areas other than the passenger compartment or luggage compartment, 
the protection degree IPXXB shall be satisfied.  
5.3.1.2.2.3.  Connectors  
  Connectors (including vehicle inlet) are deemed to meet this requiremen t if: 
(a) They comply with paragraphs 5.3.1.2.2.1. and 5.3.1.2.2.2. when separated without the use of tools; or  
(b) They are located underneath the floor and are provided with a locking mechanism; or  
(c) They are provided with a locking mechanism and other  components shall be removed with the use of tools in 
order to separate the connector; or  
(d) The voltage of the live parts becomes equal or below DC 60V or equal or below AC 30V (rms) within 1 second 
after the connector is separated.  
5.3.1.2.2.4.   Service  disconnect  
 For a service disconnect which can be opened, disassembled or removed without tools, it is acceptable if 
protection degree IPXXB is satisfied when it is opened, disassembled or removed without tools.  
5.3.1.2.2.5.   Marking  
5.3.1.2.2.5.1.  The sy mbol shown in Figure 4 shall appear on or near the REESS. The symbol background shall be 
yellow, the bordering and the arrow shall be black.  
 
 
 UAE Technical regulation  for FCV  
 Figure 4  
Marking of high voltage equipment  
 
 
5.3.1.2.2.5.2. The symbol shall be visible on enclosures and electric al protection barriers, which, when removed, 
expose live parts of high voltage circuits. This provision is optional to any connectors for high voltage buses. 
This provision shall not apply to any of the following cases  
(a) Where electrical protection barri ers or enclosures cannot be physically accessed, opened, or removed; unless 
other vehicle components are removed with the use of tools;  
(b) Where electrical protection barriers or enclosures are  located underneath the vehicle floor.  
5.3.1.2.2.5.3.  Cables  for high voltage buses which are not located within enclosures shall be identified by having an 
outer covering with the colour orange.  
5.3.1.2.3.  Protection against indirect contact  
5.3.1.2.3.1.  For protection against electric shock which could arise from i ndirect contact, the exposed conductive 
parts, such as the conductive electrical protection barrier and enclosure, shall be conductively connected and 
secured to the electrical chassis with electrical wire or ground cable, by welding, or by connection usin g bolts, 
etc. so that no dangerous potentials are produced.  
5.3.1.2.3.2.  The resistance between all exposed conductive parts and the electrical chassis shall be lower than 
0.1ohm when there is current flow of at least 0.2 amperes. Demonstrated by using o ne of the test procedures 
described in    ANNEX 1. 3.4. 
 This requirement is satisfied if the galvanic connection has been established by welding. In case of doubts a 
measurement shall be made.  
5.3.1.2.3.3.  In the case of motor vehicles which are connected to  the grounded external electric power supply 
through the conductive connection, a device to enable the conductive connection of the electrical chassis to 
the earth ground shall be provided.  
  The device shall enable connection to the earth ground before ex terior voltage is applied to the vehicle and 
retain the connection until after the exterior voltage is removed from the vehicle.  
  Compliance to this requirement may be demonstrated either by using the connector specified by the car 
manufacturer, or by ana lysis (e.g. visual inspection, drawings etc.).  
5.3.1.2.4.  Isolation resistance  monitoring system  
5.3.1.2.4.1.  In fuel cell vehicles, DC high voltage buses shall have an on -board isolation resistance monitoring 
system together with a warning to the driver i f the isolation resistance drops below the minimum required 
value of 100 ohms/volt. The function of the on -board isolation resistance monitoring system shall be 
confirmed as described in    ANNEX 1. 3.2. 
 The isolation resistance between the high voltage bus of the coupling system for charging the REESS, which 
is not energized in conditions other than that during the charging of the REESS, and the electrical chassis need 
not to be monitored.  
5.3.1.2.4.2.  Electric power train consisting of separate DC or AC bus es 
  If AC high voltage buses and DC high voltage buses are conductively isolated from each other, isolation 
resistance between the high voltage bus and the electrical chassis shall have a minimum value of 100 ohms/volt 
of the working voltage for DC buses,  and a minimum value of 500 ohms/volt of the working voltage for AC 
buses.  The measurement shall be conducted according to    ANNEX 1. 3.1.  UAE Technical regulation  for FCV  
 5.3.1.2.4.3.  Electric power train consisting of combined DC - and AC -buses  
If AC high voltage buses and DC high voltag e buses are galvanically connected, isolation resistance between the high 
voltage bus and the electrical chassis shall have a minimum value of 500 Ω/volt of the working voltage.  
  However, if all AC high voltage buses are protected by one of the two follo wing measures, isolation 
resistance between the high voltage bus and the electrical chassis shall have a minimum value of 100 ohms/volt 
of the working voltage.  
(a) Double or more layers of solid insulators, electrical protection barriers or enclosures that  meet the requirement 
in paragraph 5.3.1.2.3. independently, for example wiring harness;  
(b) Mechanically robust protections that have sufficient durability over vehicle service life such as motor 
housings, electronic converter cases or connectors.  
5.3.1. 2.4.4.  Isolation resistance requirement for the coupling system for charging the REESS.  
For the vehicle inlet intended to be conductively connected to the grounded external AC power supply and the 
electrical circuit that is conductively connected to the ve hicle inlet during charging the REESS, the isolation 
resistance between the high voltage bus and the electrical chassis shall be at least 1M ohms when the charger 
coupler is disconnected. During the measurement, the REESS may be disconnected. The measureme nt shall 
be conducted according to    ANNEX 1. 3.1. 
5.3.1.3.   Functional safety  
  At least a momentary indication shall be given to the driver when the vehicle is in "active driving possible 
mode''.  
  However, this provision does not apply under conditions wh ere an internal combustion engine provides 
directly or indirectly the vehicle´s propulsion power upon start up.  
  When leaving the vehicle, the driver shall be informed by a signal (e.g. optical or audible signal) if the vehicle 
is still in the active driv ing possible mode.  
  If the on -board REESS can be externally charged, vehicle movement by its own propulsion system shall be 
impossible as long as the connector of the external electric power supply is physically connected to the vehicle 
inlet.  
  This requ irement shall be demonstrated by using the connector specified by the car manufacturer.  
  The state of the drive direction control unit shall be identified to the driver.  
5.3.2.   Electric safety requirements – post-crash  
5.3.2.1.  General  
  Fuel cell vehicl es equipped with electric power train shall comply with the requirements of paragraphs 
5.3.2.2. to 5.3.2.4. This can be met by a separate impact test provided that the electrical components do not 
influence the occupant protection performance of the vehicl e type as defined in the impact regulation. In case 
of this condition the requirements of paras. 5.3.2.2. to 5.3.2.4. shall be checked in accordance with the methods 
set out in    ANNEX 1. 3.5. 
5.3.2.2.  Protection against electric shock  
After the impact at le ast one of the three criteria specified in paragraphs  5.3.2.2.1. to 5.3.2.2.3. shall be met.  
If the vehicle has an automatic disconnect function, or device(s) that conductively divide the electric power 
train circuit during driving condition, at least one of the following criteria shall apply to the disconnected 
circuit or to each divided circuit individually after the disconnect function is activated. However criteria 
defined in   5.3.2.2.2. shall not apply if more than a single potential of a part of the high voltage bus is not 
protected under the conditions of protection degree  IPXXB.  
In the case that the test is performed under the condition that part(s) of the high voltage system are not 
energized, the protection against electric shock shall be proved b y either   5.3.2.2.2. or   5.3.2.2.3. for the 
relevant part(s).  UAE Technical regulation  for FCV  
 5.3.2.2.1.  Absence of high voltage  
The voltages Vb, V1 and V2 of the high voltage buses shall be equal or less than 30 VAC or 60 VDC within 
60 seconds after the impact as specified in    ANNEX 1. 3.5. and    ANNEX 1. 3.5.2.2.  
5.3.2.2.2.   Isolation resistance  
The criteria specified in the paragraphs 5.3.2.2.2.1. and 5.3.2.2.2.2. below shall be met.  
The measurement shall be conducted in accordance with paragraph  ANNEX 1. 3.5.2.3. of paragraph  ANNEX 
1.3.5. 
5.3.2.2.2.1.   Electrical power train consisting of separate DC - and AC -buses  
If the AC high voltage buses and the DC high voltage buses are conductively isolated from each other, isolation 
resistance between the high voltage bus and the electrical chassis  (Ri, as defined in paragraph  ANNEX 
1.3.5.2.3.) shall have a minimum value of 100 Ω/volt of the working voltage for DC buses, and a minimum 
value of 500 Ω/volt of the working voltage for AC buses.  
5.3.2.2.2.2.   Electrical power train consisting of combined DC- and AC -buses  
If the AC high voltage buses and the DC high voltage buses are conductively connected they shall meet one 
of the following requirements:  
(a) Isolation resistance between the high voltage bus and the electrical chassis (Ri, as defined in pa ragraph  
ANNEX 1. 3.5.2.3.) shall have a  minimum value of 500 Ω/volt of the working voltage;  
(b) Isolation resistance between the high voltage bus and the electrical chassis (Ri, as defined in paragraph  
ANNEX 1. 3.5.2.3.) shall have a minimum value of 100 Ω/volt of the working voltage and the AC b us meets 
the physical protection as described in   5.3.2.2.3. ;  
(c) Isolation resistance between the high voltage bus and the electrical chassis (Ri, as defined in paragraph  
ANNEX 1. 3.5.2.3.) shall have a minimum value of 100 Ω/volt of the working voltage a nd the AC bus meets 
the absence of high voltage as described in   5.3.2.2.1.  
5.3.2.2.3.   Physical protection  
Individual Contracting Parties may elect to adopt the physical protection. For protection against direct contact 
with high voltage live parts, the protection degree  IPXXB shall be provided.  
In addition, for protection against electric shock which could arise from indirect contact, the resistance 
between all exposed conductive parts and electrical chassis shall be lower than 0.1 ohm when there is curr ent 
flow of at least 0.2 amperes.  
This requirement is satisfied if the galvanic connection has been established by welding. In case of doubts a 
measurement shall be made.  
5.3.2.3.  Electrolyte spillage  
In the period from the impact until 30 minutes after no  electrolyte from the REESS shall spill into the passenger 
compartment and no more than 7 per cent of electrolyte shall spill from the REESS outside the passenger 
compartment.  
The manufacturer shall demonstrate compliance in accordance with paragraph  ANNEX 1. 3.5.2.  ANNEX 1.   
5.3.2.4.  REESS  retention  
REESS located inside the passenger compartment shall remain in the location in which they are installed and 
REESS components shall remain inside REESS boundaries.  
No part of any REESS that is located outside the pa ssenger compartment for electric safety assessment shall 
enter the passenger compartment during or after the impact test.  
The manufacturer shall demonstrate compliance in accordance with paragraph  ANNEX 1. 3.5.2.7.  UAE Technical regulation  for FCV  
  ANEX 1   Test conditions and procedures  
 
 1.  Compliance tests for fuel system integrity  
 1.1.  Post-crash compressed hydrogen storage system leak test  
The crash tests used to evaluate post -crash hydrogen leakage are those already applied in the jurisdictions of each 
contracting party.  
Prior to c onducting the crash test, instrumentation is installed in the hydrogen storage system to perform the required 
pressure and temperature measurements if the standard vehicle does not already have instrumentation with the 
required accuracy.  
The storage system  is then purged, if necessary, following manufacturer directions to remove impurities from the 
container before filling the storage system with compressed hydrogen or helium gas. Since the storage system 
pressure varies with temperature, the targeted fill pressure is a function of the temperature. The target pressure 
shall be determined from the following equation:  
Ptarget = NWP x (273 + T o) / 288  
where NWP is the nominal working pressure (MPa), T o is the ambient temperature to which the storage system is 
expected to settle, and P target is the targeted fill pressure after the temperature settles.  
The container is filled to a minimum of 95 per cent of the targeted fill pressure and allowed to settle (stabilize) prior 
to conducting the crash test.  
The main sto p valve and shut -off valves for hydrogen gas, located in the downstream hydrogen gas piping, are kept 
open immediately prior to the impact.  
 1.1.1.  Post-crash leak test - compressed hydrogen storage system filled with compressed hydrogen  
The hydrogen gas p ressure, P 0 (MPa), and temperature, T 0 (°C), is measured immediately before the impact and then 
at a time interval, Δt (min), after the impact. The time interval, Δt, starts when the vehicle comes to rest after 
the impact and continues for at least 60 minu tes. The time interval, Δt, is increased if necessary in order to 
accommodate measurement accuracy for a storage system with a large volume operating up to 70MPa; in that 
case, Δt can be calculated from the following equation:  
Δt = V CHSS x NWP /1000 x (( -0.027 x NWP +4) x R s – 0.21) -1.7 x R s  
where R s = P s / NWP, P s is the pressure range of the pressure sensor (MPa), NWP is the Nominal Working Pressure 
(MPa), V CHSS is the volume of the compressed hydrogen storage system (L), and Δt is the time inter val (mi n). 
If the calculated value of Δt is less than 60 minutes, Δt is set to 60 minutes.  
The initial mass of hydrogen in the storage system can be calculated as follows:  
Po’ = P o x 288 / (273 + T 0) 
ρo’ = –0.0027 x (P 0’)2 + 0.75 x P 0’ + 0.5789  
Mo = ρo’ x V CHSS 
Correspondingly, the final mass of hydrogen in the storage system, M f, at the end of the time inter val, Δt, can be 
calculated as follows:  
Pf’ = P f x 288 / (273 + T f) 
ρf’ = –0.0027 x (P f’)2 + 0.75 x P f’ + 0.5789  
Mf = ρ f’ x V CHSS 
where P f is the measured fina l pressure (MPa) at the end of the time interval, and T f is the measured final temperature 
(°C).  
The average hydrogen flow rate over the time interval (that shall be less than the criteria in   5.2.2.1.) is therefore  UAE Technical regulation  for FCV  
 VH2 = (M f-Mo) / Δt x 22.41 / 2.016 x (P target /Po) 
where V H2 is the average volumetric flow rate (NL/min) over the time interval and the term (P target /Po) is used to 
compensate for differences between the measured initial pressure, P o, and the targeted fill pressure P target. 
 1.1.2.  Post-crash  leak test - Compressed hydrogen storage system filled with compressed helium  
The helium gas pressure, P 0 (MPa), and temperature T 0 (°C), are measured immediately before the impact and then at 
a predetermined time interval after the impact. The time interv al, Δt, starts when the vehicle comes to rest 
after the impact and continues for at least 60 minutes.  
The time interval, Δt, shall be increased if necessary in order to accommodate measurement accuracy for a storage 
system with a large volume operating up to 70MPa; in that case, Δt can be calculated from the following 
equation:  
Δt = V CHSS x NWP /1000 x (( -0.028 x NWP +5.5) x R s – 0.3) – 2.6 x R s  
where R s = P s / NWP, P s is the pressure range of the pressure sensor (MPa), NWP is the Nominal Working Pressure 
(MPa), V CHSS is the volume of the compressed storage system (L), and Δt is the time inter val (min). If the 
value of Δt is less than 60 minutes, Δt is set to 60 minutes.  
The initial mass of hydrogen in the storage system is calculated as follows:  
Po’ = P o x 288 / (273 + T 0) 
ρo’ = –0.0043 x (P 0’)2 + 1.53 x P 0’ + 1.49  
Mo = ρo’ x V CHSS 
The final mass of hydrogen in the storage system at the end of the time inter val, Δt, is calculated as follows:  
Pf’ = P f x 288 / (273 + T f) 
ρf’ = –0.0043 x (P f’)2 + 1.53 x P f’ + 1.49 
Mf = ρ f’ x V CHSS 
where P f is the measured final pressure (MPa) at the end of the time interval, and T f is the measured final temperature 
(°C). 
The average helium flow rate over the time interval is therefore  
VHe = (M f-Mo) / Δt x 22.41 / 4.003 x (P o/ Ptarget) 
 
where V He is the average volumetric flow rate (NL/min) over the time interval and the term P o/ P target is used to 
compensate for differences between the measured initial pressure (P o) and the targeted fill pressure (P target). 
Conversion of the ave rage volumetric flow of helium to the average hydrogen flow is done with the following 
expression:  
VH2 = V He / 0.75 
where V H2 is the corresponding average volumetric flow of hydrogen  (that  shall be less than the criteria in   
5.2.2.1. to pass).  
 1.2.  Post-crash concentration test for enclosed spaces  
The measurements are recorded in the crash test that evaluates potential hydrogen (or helium) leakage (   1.1.  test 
procedure).  
Sensors are selected to measure either the build -up of the hydrogen or helium gas  or the reduction in oxygen (due to 
displacement of air by leaking hydrogen/helium).  
Sensors are calibrated to traceable references to ensure an accuracy of ±5 per cent at the targeted criteria of 4 per cent 
hydrogen or 3 per cent helium by volume in air, and a full scale measurement capability of at least 25 per cent 
above the target criteria. The sensor shall be capable of a 90 per cent response to a full scale change in 
concentration within 10 seconds.  UAE Technical regulation  for FCV  
 Prior to the crash impact, the sensors are located i n the passenger, luggage, and cargo compartments of the vehicle as 
follows:  
(a) At a distance within 250 mm of the headliner above the driver’s seat or near the top centre the passenger 
compartment;  
(b) At a distance within 250 mm of the floor in front of the rear (or rear most) seat in the passenger compartment;  
(c) At a distance within 100 mm of the top of luggage and cargo compartments within the vehicle that are not 
directly affected by the particular crash impact to be conducted.  
The sensors are secure ly mounted on the vehicle structure or seats and protected for the planned crash test from debris, 
air bag exhaust gas and projectiles. The measurements following the crash are recorded by instruments located 
within the vehicle or by remote transmission.  
The vehicle may be located either outdoors in an area protected from the wind and possible solar effects or indoors in 
a space that is large enough or ventilated to prevent the build -up of hydrogen to more than 10 per cent of the 
targeted criteria in the pa ssenger, luggage, and cargo compartments.  
Post-crash data collection in enclosed spaces commences when the vehicle comes to a rest. Data from the sensors are 
collected at least every 5 seconds and continue for a period of 60 minutes after the test. A first -order lag (time 
constant) up to a maximum of 5 seconds may be applied to the measurements to provide "smoothing" and 
filter the effects of spurious data points.  
The filtered readings from each sensor shall be below the targeted criteria of 3±1.0 per cent for hydrogen and 2.25 
± 0.75 per cent for helium at all times throughout the 60 minutes post -crash test period.  
 1.3.  Compliance test for single failure conditions  
Either test procedure of    1.3.1. or    1.3.2. shall be executed:  
 1.3.1.  Test procedure f or vehicle equipped with hydrogen gas leakage detectors  
 1.3.1.1. Test condition  
 1.3.1.1.1  Test vehicle : The propulsion system of the test vehicle is started, warmed up to its normal operating 
temperature, and left operating for the test duration. If the  vehicle is not a fuel cell vehicle, it is warmed up 
and kept idling. If the test vehicle has a system to stop idling automatically, measures are taken so as to prevent 
the engine from stopping.  
 1.3.1.1.2.  Test gas : Two mixtures of air and hydrogen gas: 2 ± 1.0 per cent concentration (or less) of hydrogen 
in the air to verify function of the warning, and 3±1.0  per cent concentration (or less) of hydrogen in the air to 
verify function of the shut -down. The proper concentrations are selected based on the rec ommendation (or the 
detector specification) by the manufacturer.  
 1.3.1.2.  Test method  
 1.3.1.2.1.  Preparation for the test : The test is conducted without any influence of wind.  
(a) A test gas induction hose is attached to the hydrogen gas leakage detector ; 
(b) The hydrogen leak detector is enclosed with a cover to make gas stay around hydrogen leak detector.  
 1.3.1.2.2.  Execution  of the test   
(a) Test gas is blown to the hydrogen gas leakage detector;  
(b) Proper function of the warning system is confirmed when tested with the gas to verify function of the warning;  
(c) The main shut -off valve is confirmed to be closed when tested with the gas to verify function of the shut -
down. For example, the monitoring of the electric power to the shut -off valve or of th e sound of the shut -off 
valve activation may be used to confirm the operation of the main shut -off valve of the hydrogen supply.  UAE Technical regulation  for FCV  
  1.3.2.  Test procedure for integrity of enclosed spaces and detection systems.  
 1.3.2.1.  Preparation : 
 1.3.2.1.1.  The test is c onducted without any influence of wind.  
 1.3.2.1.2.  Special attention is paid to the test environment as during the test flammable mixtures of hydrogen 
and air may occur.  
 1.3.2.1.3.  Prior to the test the vehicle is prepared to allow remotely controllable hydrogen releases from the 
hydrogen system. The number, location and flow capacity of the release points downstream of the main 
hydrogen shutoff valve are defined by the vehicle manufacturer taking worst case leakage scenarios into 
account. As a minimum, t he total flow of all remotely controlled releases shall be adequate to trigger 
demonstration of the automatic "warning" and hydrogen shut -off functions.  
 1.3.2.1.4.  For the purpose of the test, a hydrogen concentration detector is installed where hydrogen gas may 
accumulate most in the passenger compartment (e.g. near the headliner ) when testing for compliance with   
5.2.1.4.2. and hydrogen concentration detectors are installed in enclosed or semi enclosed volumes on the 
vehicle where hydrogen can accumulat e from the simulated hydrogen releases when testing for compliance 
with   5.2.1.4.3. (see  
   1.3.2.1.3.).  
 1.3.2.2.  Procedure : 
 1.3.2.2.1.  Vehicle doors , windows and other covers are closed.  
 1.3.2.2.2. The propulsion  system is started  , allowed to warm up to its normal operating temperature and left 
operating at idle for the test duration.  
 1.3.2.2.3.  A leak is simulated using the remote controllable function.  
 1.3.2.2.4.  The hydrogen  concentration is measured continuously until the concentration does no t rise for 3 
minutes. When testing for compliance with   5.2.1.4.3., t he simulated leak is then increased using the remote 
controllable function until the main hydrogen shutoff valve is closed and the tell -tale warning signal is 
activated. The monitoring o f the electric power to the shut -off valve or of the sound of the shut -off valve 
activation may be used to confirm the operation of the main shut -off valve of the hydrogen supply.  
 1.3.2.2.5.  When testing for compliance with   5.2.1.4.2., the test is succe ssfully completed if the hydrogen 
concentration in the passenger compartment does not exceed 1.0 per cent. When testing for compliance 
with   5.2.1.4.3., the test is successfully completed if the tell -tale warning and shut -off function are executed 
at (or below) the levels specified in   5.2.1.4.3.; otherwise, the test is failed and the system is not qualified for 
vehicle service.  
 1.4.  Compliance test for the vehicle exhaust system  
 1.4.1.  The power system of the test vehicle (e.g. fuel cell stack or engi ne) is warmed up to its normal operating 
temperature.  
 1.4.2.  The measuring  device is warmed up before use to its normal operating temperature.  
 1.4.3.  The measuring  section of the measuring device is placed on the centre line of the exhaust gas flow withi n 100 
mm from the exhaust gas outlet external to the vehicle.  
 1.4.4.  The exhaust hydrogen concentration is continuously measured during the following steps:  
(a) The power system is shut down;  
(b) Upon completion of the shut -down process, the power system is immediately started;  
(c) After a lapse of one minute, the power system is turned off and measurement continues until the power system 
shut-down procedure is completed.  
 1.4.5.  The measurement device shall have a measurement response time of less than 30 0 milliseconds.  
 1.5.  Compliance test for fuel line leakage  UAE Technical regulation  for FCV  
  1.5.1.  The power system of the test vehicle (e.g. fuel cell stack or engine) is warmed up and operating at its normal 
operating temperature with the operating pressure applied to fuel lines.  
 1.5.2. Hydrogen leakage is evaluated at accessible sections of the fuel lines from the high -pressure section to the 
fuel cell stack (or the engine), using a gas detector or leak detecting liquid, such as soap solution.  
 1.5.3.  Hydrogen leak detection is perf ormed primarily at joints  
 1.5.4.  When a gas leak detector is used, detection is performed by operating the leak detector for at least 10 seconds 
at locations as close to fuel lines as possible.  
 1.5.5.  When a leak detecting liquid is used, hydrogen gas le ak detection is performed immediately after applying the 
liquid. In addition, visual checks are performed a few minutes after the application of liquid in order to check 
for bubbles caused by trace leaks.  
 1.   Installation verification  
The system is visua lly inspected for compliance.  
 2.  Test procedures for compressed hydrogen storage  
 2.1. Test procedures  for qualification requirements of compressed hydrogen storage are organized as follows:  
 Section  2.2 is the test procedures for baseline performance m etrics (requirement of   5.1.1.)  
 Paragraph  2.3 is the test procedures for performance durability (requirement of   5.1.2.)  
 Paragraph  2.4 is the test procedures for expected on -road performance (requirement of   5.1.3.)  
 Paragraph  2.5 is the test proce dures for service terminating performance in Fire (requirement of   5.1.4.)  
 Paragraph  2.6 is the test procedures for performance durability of primary closures (requirement of   5.1.5.)  
 2.2.  Test procedures for baseline performance metrics (requirement  of   5.1.1.)  
 2.2.1.  Burst test (hydraulic)  
The burst test is conducted at 20( ±5)°C using a non -corrosive fluid. The rate of pressurization is less than or equal to 
1.4 MPa/s for pressures higher than 150 per cent of the nominal working pressure. If the rate exceeds 
0.35 MPa/s at pressures higher than 150 per cent  NWP, then either the container is placed in series between 
the pressure source and the pressure measurement device, or the time at the pressure above a target burst 
pressure exceeds 5  seconds. T he burst pressure of the container shall be recorded.  
 2.2.2.  Pressure cycling test (hydraulic)  
The test is performed in accordance with the following procedure:  
(a) The container is filled with a non -corrosive fluid;  
(b) The container and fluid are stabi lized at the specified temperature and relative humidity at the start of testing; 
the environment, fuelling fluid and container skin are maintained at the specified temperature for the duration 
of the testing. The container temperature may vary from the en vironmental temperature during testing;  
(c) The container is pressure cycled between 2  (±1) MPa and the target pressure at a rate not exceeding 10  cycles 
per minute for the specified number of cycles;  
(d) The temperature of the hydraulic fluid within the c ontainer is maintained and monitored at the specified 
temperature.  
 2.3.  Test procedures for performance durability ( requirement of   5.1.2.)  
 2.3.1.  Proof pressure test  
The system is pressurized smoothly and continually with a non -corrosive hydraulic fl uid until the target test pressure 
level is reached and then held for the specified time.  
 2.3.2.  Drop (impact) test (unpressurized)  UAE Technical regulation  for FCV  
 The storage container is drop tested at ambient temperature without internal pressurization or attached valves. The 
surfa ce onto which the containers are dropped shall be a smooth, horizontal concrete pad or other flooring 
type with equivalent hardness.  
(a) The orientation of the container being dropped (per requirement of   5.1.2.2.) is determined as follows: One 
or more ad ditional container(s) shall be dropped in each of the orientations described below. The drop 
orientations may be executed with a single container or as many as four containers may be used to accomplish 
the four drop orientations.  
(i) Dropped once from a ho rizontal position with the bottom 1.8  m above the surface onto which it is dropped;  
(ii) Dropped once onto the end of the container from a vertical position with the ported end  upward with a potential 
energy of not less than 488 J, with the height of the l ower end no greater than 1.8  m; 
(iii)   Dropped once onto the end of the container from a vertical position with the ported end downward with a 
potential energy of not less than 488 J, with the height of the lower end no greater than 1.8  m. If the containe r 
is symmetrical (identical ported ends), this drop orientation is not required ; 
(iv) Dropped once at a 45° angle from the vertical orientation with a ported end downward with its centre of gravity 
1.8 m above the ground. However, if the bottom is closer t o the ground than 0.6  m, the drop angle shall be 
changed to maintain a minimum height of 0.6  m and a centre of gravity of 1.8  m above the ground.  
The four drop orientations are illustrated below.  
Figure 5  
Drop orientations  
 
  
No attempt shall be made to  prevent the bouncing of containers, but the containers may be prevented from falling over 
during the vertical drop test described in b) above.  
If more than one container is used to execute all three drop specifications, then those containers shall underg o pressure 
cycling according to     2.2.2. until either leakage or 22,000 cycles without leakage have occurred. Leakage 
shall not occur within number of Cycles (5,500, 7,500 or 11,000).  
The orientation of the container being dropped per requirement   5.1.2 .2. shall be identified as follows:  
(a) If a single container was subjected to all four drop orientations, then the container being dropped per 
requirement of   5.1.2.2. shall be dropped in all four orientations;  
(b) If more than one container is used to e xecute the four drop orientations, and if all containers reach 22,000 
cycles without leakage, then the orientation of the container being dropped per requirement   5.1.2.2. is the 
45o orientation (iv), and that container shall then undergo further testing as specified in paragraph 5.1.2. ;  
1.8m 
> 
488J 
< 
1.8 m 
45 
o 
> 
0.6m 
No. 1 
 N o. 
2 
 No.  
3* 
No.  
4 
center of gravity  UAE Technical regulation  for FCV  
 (c) If more than one container is used to execute the four drop orientations and if any container does not reach 
22,000 cycles without leakage, then the new container shall be subjected to the drop orientation(s) that res ulted 
in the lowest number of cycles to leakage and then will undergo further testing as specified in paragraph 5.1.2 . 
 2.3.3.  Surface damage test (unpressurized)  
The test proceeds in the following sequence:  
(a) Surface flaw generation: Two longitudinal s aw cuts are made on the bottom outer surface of the unpressurized 
horizontal storage container along the cylindrical zone close to but not in the shoulder area. The first cut is at 
least 1.25  mm deep and 25  mm long toward the valve end of the container. Th e second cut is at least 0.75  mm 
deep and 200  mm long toward the end of the container opposite the valve;  
(b) Pendulum impacts: The upper section of the horizontal storage container is divided into five distinct (not 
overlapping) areas 100  mm in diameter e ach (see Figure 6). After 12 hours preconditioning at – 40 °C in an 
environmental chamber, the centre of each of the five areas sustains the impact of a pendulum having a 
pyramid with equilateral faces and square base, the summit and edges being rounded to  a radius of 3  mm. The 
centre of impact of the pendulum coincides with the centre of gravity of the pyramid. The energy of the 
pendulum at the moment of impact with each of the five marked areas on the container is 30 J. The container 
is secured in place d uring pendulum impacts and not under pressure.  
Figure 6  
Side view of tank  
 
 2.3.4.  Chemical exposure and ambient temperature pressure cycling test  
Each of the 5 areas of the unpressurized container preconditioned by pendulum impact (paragraph  4.2.5.2.) i s exposed 
to one of five solutions:  
(a) 19 per cent (by volume) sulphuric acid in water (battery acid);  
(b) 25 per cent (by weight) sodium hydroxide in water;  
(c) 5 per cent (by volume) methanol in gasoline (fluids in fuelling stations);  
(d) 28 per cent (b y weight) ammonium nitrate in water (urea solution); and  
(e) 50 per cent (by volume) methyl alcohol in water (windshield washer fluid).  
 The test container is oriented with the fluid exposure areas on top. A pad of glass wool approximately 0.5  mm 
thick and  100 mm in diameter is placed on each of the five preconditioned areas. A sufficient amount of the 
test fluid is applied to the glass wool sufficient to ensure that the pad is wetted across its surface and through 
its thickness for the duration of the test . 
 The exposure of the container with the glass wool is maintained for 48  hrs with the container held at 125 per 
cent NWP (applied hydraulically) and 20 (±5) °C before the container is subjected to further testing.  
 Pressure cycling is performed to the spe cified target pressures according to paragraph  2.2.2. at 20 ( ±5)°C for 
the specified numbers of cycles. The glass wool pads are removed and the container surface is rinsed with 
water the final 10 cycles to specified final target pressure are conducted.  
 2.3.5. Static pressure test (hydraulic)  
“Side”View of Tank“Side”View of TankUAE Technical regulation  for FCV  
 The storage system is pressurized to the target pressure in a temperature -controlled chamber. The temperature of the 
chamber and the non -corrosive fuelling fluid is held at the target temperature within ±5°C for the specified 
duration.  
 2.4. Test procedures for expected on -road performance (  5.1.3.)  
  (Pneumatic test procedures are provided; hydraulic test elements are described in    3.2.)  
 2.4.1.  Gas pressure cycling test (pneumatic)  
At the onset of testing, the s torage system is stabilized at the specified temperature, relative humidity and fuel level 
for at least 24  hrs. The specified temperature and relative humidity is maintained within the test environment 
throughout the remainder of the test. (When required i n the test specification, the system temperature is 
stabilized at the external environmental temperature between pressure cycles.) The storage system is pressure 
cycled between less than 2 (+0/-1) MPa and the specified maximum pressure ( ±1MPa). If system co ntrols that 
are active in vehicle service prevent the pressure from dropping below a specified pressure, the test cycles 
shall not go below that specified pressure. The fill rate is controlled to a constant 3 -minute pressure ramp rate, 
but with the fuel fl ow not to exceed 60 g/s; the temperature of the hydrogen fuel dispensed to the container is 
controlled to the specified temperature. However, the pressure ramp rate should  be decreased if the gas 
temperature in the container exceeds +85°C. The defuelling r ate is controlled to greater than or equal to the 
intended vehicle’s maximum fuel -demand rate. The specified number of pressure cycles is conducted. If 
devices and/or controls are used in the intended vehicle application to prevent an extreme internal temp erature, 
the test may be conducted with these devices and/or controls (or equivalent measures).  
 2.4.2.  Gas permeation test (pneumatic)  
A storage system is fully filled with hydrogen gas at 115 per cent NWP (full fill density equivalent to 100 per 
cent NWP at +15  °C is 113 per cent NWP at +55  °C) and held at  +55 °C in a sealed container until steady -
state permeation or 30 hours, whichever is longer. The total steady -state discharge rate due to leakage and 
permeation from the storage system is measured.  
 2.4.3.  Localized gas leak test (pneumatic)  
A bubble test may be used to fulfil this requirement. The following procedure is used when conducting the bubble 
test: 
(a) The exhaust of the shutoff valve (and other internal connections to hydrogen systems) sha ll be capped for this 
test (as the test is focused at external leakage).  
 At the discretion of the tester, the test article may be immersed in the leak -test fluid or leak -test fluid applied 
to the test article when resting in open air. Bubbles can vary gre atly in size, depending on conditions. The 
tester estimates the gas leakage based on the size and rate of bubble formation.  
(b) Note : For a localized rate of 0.005 mg/sec (3.6 NmL/min), the resultant allowable rate of bubble generation is 
about 2,030 bubb les per minute for a typical bubble size of 1.5 mm in diameter. Even if much larger bubbles 
are formed, the leak should be readily detectable. For an unusually large bubble size of 6 mm in diameter, the 
allowable bubble rate would be approximately 32 bubbl es per minute.  
 2.5. Test procedures for service terminating performance in fire (  5.1.4.)  
 2.5.1.  Fire test  
 The hydrogen container assembly consists of the compressed hydrogen storage system with additional relevant 
features, including the venting syste m (such as the vent line and vent line covering) and any shielding affixed 
directly to the container (such as thermal wraps of the container(s) and/or coverings/barriers over the 
TPRD(s)).  
 Either one of the following two methods are used to identify the p osition of the system over the initial 
(localized) fire source:  
 2.5.1.1.  Method 1: Qualification for a generic (non -Specific) vehicle installation  
 If a vehicle installation configuration is not specified (and the qualification of the system is not limite d to a 
specific vehicle installation configuration) then the localized fire exposure area is the area on the test article UAE Technical regulation  for FCV  
 farthest from the TPRD(s). The test article, as specified above, only includes thermal shielding or other 
mitigation devices affixed d irectly to the container that are used in all vehicle applications. Venting system(s) 
(such as the vent line and vent line covering) and/or coverings/barriers over the TPRD(s) are included in the 
container assembly if they are anticipated for use in any ap plication. If a system is tested without representative 
components, retesting of that system is required if a vehicle application specifies the use of these type of 
components.  
 2.5.1.2.  Method 2: Qualification for a specific vehicle installation  
 If a spe cific vehicle installation configuration is specified and the qualification of the system is limited to that 
specific vehicle installation configuration, then the test setup may also include other vehicle components in 
addition to the hydrogen storage syst em. These vehicle components (such as shielding or barriers, which are 
permanently attached to the vehicle’s structure by means of welding or bolts and not affixed to the storage 
system) shall be included in the test setup in the vehicle -installed configur ation relative to the hydrogen storage 
system. This localized fire test is conducted on the worst case localized fire exposure areas based on the four 
fire orientations: fires originating from the direction of the passenger compartment, cargo/luggage 
compa rtment, wheel wells or ground -pooled gasoline.  
 The container may be subjected to engulfing fire without any shielding components, as described in paragraph  
2.5.2.  
 The following test requirements apply whether Method 1 or 2 (above) is used:  
(a) The conta iner assembly is filled with compressed hydrogen gas at 100  per cent of NWP. The container 
assembly is positioned horizontally approximately 100 mm above the fire source. (Note: as stated in   5.1.4., 
contracting parties under the 1998 Agreement may choose  to use compressed air as an alternative test gas for 
certification of the container for use in their countries or regions.) ;  
Localized portion of the fire test  
(b) The localized fire exposure area is located on the test article furthest from the TPRD(s).  If Method 2 is selected 
and more vulnerable areas are identified for a specific vehicle installation configuration, the more vulnerable 
area that is furthest from the TPRD(s) is positioned directly over the initial fire source;  
(c) The fire source consist s of LPG burners configured to produce a uniform minimum temperature on the test 
article measured with a minimum 5 thermocouples covering the length of the test article up to 1.65 m 
maximum (at least 2 thermocouples within the localized fire area, and at l east 3 thermocouples equally spaced 
and no more than 0.5 m apart in the remaining area) located 25 mm ± 10mm from the outside surface of the 
test article along its longitudinal axis. At the option of the manufacturer or testing facility, additional 
thermoc ouples may be located at TPRD sensing points or any other locations for optional diagnostic purposes;  
(d) Wind shields are applied to ensure uniform heating;  
(e) The fire source initiates within a 250 mm ±50 mm longitudinal expanse positioned under the loc alized 
exposure area of the test article. The width of the fire source encompasses the entire diameter (width) of the 
storage system. If Method 2 is selected, the length and width shall be reduced, if necessary, to account for 
vehicle -specific features;  
(f) As shown in Figure 7 the temperature of the thermocouples in the localized fire area has increased 
continuously to at least 300 °C within 1 minute of ignition, to at least 600 °C within 3 minutes of ignition, and 
a temperature of at least 600  °C is maint ained for the next 7 minutes. The temperature in the localized fire area 
shall not exceed 900  °C during this period. Compliance to the thermal requirements begins 1 minute after 
entering the period with minimum and maximum limits and is based on a 1 -minute  rolling average of each 
thermocouple in the region of interest. (Note: The temperature outside the region of the initial fire source is 
not specified during these initial 10 minutes from the time of ignition.).  UAE Technical regulation  for FCV  
 Figure 7  
Temperature profile of fire test  
 
  Engulfing portion of the fire test  
 Within the next 2 -minute interval, the temperature along the entire surface of the test article shall be increased 
to at least 800 °C and the fire source is extended to produce a uniform temperature along the entire le ngth up 
to 1.65 meters and the entire width of the test article (engulfing fire). The minimum temperature is held at 
800°C, and the maximum temperature shall not exceed 1100 °C. Compliance to thermal requirements begins 
1 minute after entering the period w ith constant minimum and maximum limits and is based on a 1 -minute 
rolling average of each thermocouple.  
 The test article is held at temperature (engulfing fire condition) until the system vents through the TPRD and 
the pressure falls to less than 1 MPa. The venting shall be continuous (without interruption), and the storage 
system shall not rupture. An additional release through leakage (not including release through the TPRD) that 
results in a flame with length greater than 0.5 m beyond the perimeter of the applied flame shall not occur.  
1 600oC800oCLocalized Fire Exposure Engulfing Fire
Minutes 12 10300oC
3 Min
Temp
Localized  Area
Engulfing Region Outside 
Localized Area (burner 
ramp rate)
Ignite 
Main 
Burner
0UAE Technical regulation  for FCV  
 Table 2  
 Summary of fire test protocol  
  Localized fire region  Time period  Engulfing fire region                              
(Outside the localized fire 
region)  
Action  Ignite Burners  0-1 minute  No Burner Operation  
Minimum temperature  Not specified    Not specified  
Maximum temperature  Less than 900oC   Not specified  
Action  Increase temperature and 
stabilize fire for 
start of localized 
fire exposure  1-3 minutes  No Burner Operation  
Minimum temperature  Greater than 300oC   Not specified  
Maximum temperature  Less than 900oC   Not specified  
Action  
 Localized fire exposure 
continues  3-10 minutes   No Burner Operation  
 
Minimum temperature  1-minute rolling average                                        
greater than 600oC   Not specified  
Maximum temperature  1-minute rolling average                                             
less than 900oC  Not specified  
Action  Increase temperature  10-11 minutes   Main Burner Ignited at 10 minutes  
Minimum Temperature  1-minute rolling ave rage                                          
greater than 600oC   Not specified  
Maximum temperature  1-minute rolling average                                    
less than 1,100oC  Less than 1,100oC 
Action  Increase temperature and 
stabilize fire for 
start of engulfing 
fire exposure  11-12 minutes  Increase temperature and stabilize 
fire for start of engulfing 
fire exposure  
Minimum temperature  1-minute rolling average 
greater than 600oC  Greater than 300oC 
Maximum temperature  1 minute rolling average 
less than 1,100oC  Less than 1,100oC 
Action  Engulfing fire exposure 
continues  12 minutes - end of 
test Engulfing fire exposure continues  
Minimum temperature  1-minute rolling average 
greater than 800oC  1-minute rolling average greater 
than 800oC 
Maximum tempe rature  1 minute rolling average 
less than 1,100oC  1-minute rolling average less than 
1,100oC 
 UAE Technical regulation  for FCV  
 Documenting results of the fire test  
 The arrangement of the fire is recorded in sufficient detail to ensure the rate of heat input to the test article is 
repro ducible. The results include the elapsed time from ignition of the fire to the start of venting through the 
TPRD(s), and the maximum pressure and time of evacuation until a pressure of less than 1  MPa is reached. 
Thermocouple temperatures and container pre ssure are recorded at intervals of every 10  sec or less during the 
test. Any failure to maintain specified minimum temperature requirements based on the 1 -minute rolling 
averages invalidates the test result. Any failure to maintain specified maximum temper ature requirements 
based on the 1 -minute rolling averages invalidates the test result only if the test article failed during the test.  
 2.5.2.  Engulfing fire test:  
 The test unit is the compressed hydrogen storage system. The storage system is filled with compressed 
hydrogen gas at 100 per cent NWP. The container is positioned horizontally with the container bottom 
approximately 100 mm above the fire source. Metallic shielding is used to prevent direct flame impingement 
on container valves, fittings, and/or  pressure relief devices. The metallic shielding is not in direct contact with 
the specified fire protection system (pressure relief devices or container valve).  
 A uniform fire source of 1.65 m length provides direct flame impingement on the container sur face across its 
entire diameter. The test shall continue until the container fully vents (until the container pressure falls below 
0.7 MPa (100 psi)). Any failure or inconsistency of the fire source during a test shall invalidate the result.  
 Flame tempera tures shall be monitored by at least three thermocouples suspended in the flame approximately 
25 mm below the bottom of the container. Thermocouples may be attached to steel cubes up to 25 mm on a 
side. Thermocouple temperature and the container pressure s hall be recorded every 30 seconds during the test.  
 Within five minutes after the fire is ignited, an average flame temperature of not less than 590°C (as 
determined by the average of the two thermocouples recording the highest temperatures over a 60 secon d 
interval) is attained and maintained for the duration of the test.  
 If the container is less than 1.65 m in length, the centre of the container shall be positioned over the centre of 
the fire source. If the container is greater than 1.65  m in length, the n if the container is fitted with a pressure 
relief device at one end, the fire source shall commence at the opposite end of the container. If the container 
is greater than 1.65 m in length and is fitted with pressure relief devices at both ends, or at mor e than one 
location along the length of the container, the centre of the fire source shall be centred midway between the 
pressure relief devices that are separated by the greatest horizontal distance.  
 The container shall vent through a pressure relief dev ice without bursting.  
 2.  Test Procedures for performance durability of primary closures (  5.1.5. requirement).  
 2. 1. Compressed hydrogen storage TPRD qualification performance tests  
 Testing is performed with hydrogen gas having gas quality compliant w ith ISO 14687 -2/SAE J2719. All tests 
are performed at ambient temperature 20 ( ±5)°C unless otherwise specified. The TPRD qualification 
performance tests are specified as follows:  
 2. 1.1.  Pressure cycling test.  
 Five TPRD units undergo 11,000 internal pres sure cycles with hydrogen gas having gas quality compliant 
with ISO 14687 -2/SAE J2719. The first five pressure cycles are between 2  (±1)MPa and 150 per cent NWP 
(±1MPa); the remaining cycles are between 2  (±1)MPa and 125 per cent NWP (±1MPa). The first 150 0 
pressure cycles are conducted at a TPRD temperature of 85  °C or higher. The remaining cycles are conducted 
at a TPRD temperature of 55 ( ±5) °C. The maximum pressure cycling rate is ten cycles per minute. Following 
this test, the pressure relief device sh all comply the requirements of the Leak Test (   2. 1.8.), Flow Rate Test 
(   2. 1.10.) and the Bench Top Activation Test (   2. 1.9.).  
 2. 1.2.  Accelerated life test.  
 Eight TPRD units undergo testing; three at the manufacturer’s specified activation temp erature, Tact, and five 
at an accelerated life temperature,  
Tlife = 9.1 x Tact0.503. The TPRD is placed in an oven or liquid bath with the temperature held constant 
(±1 °C). The hydrogen gas pressure on the TPRD inlet is 125 per cent NWP ( ±1MPa). The pres sure supply UAE Technical regulation  for FCV  
 may be located outside the controlled temperature oven or bath. Each device is pressured individually or 
through a manifold system. If a manifold system is used, each pressure connection includes a check valve to 
prevent pressure depletion of t he system when one specimen fails. The three TPRDs tested at tact shall activate 
in less than ten hours. The five TPRDs tested at Tlife shall not activate in less than 500 hours.  
 2. 1.3.  Temperature cycling test  
(a) An unpressurized TPRD is placed in a li quid bath maintained at -40°C or lower  at least two hours. The TPRD 
is transferred to a liquid bath maintained at 85  °C or higher  within five minutes, and maintained at that 
temperature at least two hours. The TPRD is transferred to a liquid bath maintaine d at -40 °C or lower  within 
five minutes ; 
(b) Step (a) is repeated until 15 thermal cycles have been achieved;  
(c) With the TPRD conditioned for a minimum of two hours in the -40°C  or lower  liquid bath, the internal pressure 
of the TPRD is cycled with hydr ogen gas between 2MPa (+1/-0MPa ) and 80 per cent NWP (+2/-0MPa ) for 100 
cycles while the liquid bath is maintained at – 40 °C or lower ; 
(d) Following  the thermal and pressure cycling, the pressure relief device  shall  comply with  the requirements of 
the Lea k Test (   2. 1.8.), except that the Leak Test  shall be  conducted at -40 °C (+5/-0°C). After the Leak Test, 
the TPRD shall comply with the requirements of  the Bench Top Activation Test (   2. 1.9 .) and then the Flow 
Rate Test (   2. 1.10.).  
 2. 1.4.  Salt c orrosion resistance test  
Two TPRD units are tested. Any non -permanent outlet caps are removed. Each TPRD unit is installed in a test fixture 
in accordance with the manufacturer’s recommended procedure so that external exposure is consistent with 
realistic installation. Each unit is exposed for 500 hours to a salt spray (fog) test as specified in ASTM B117 
(Standard Practice for Operating Salt Spray (Fog) Apparatus) except that in the test of one unit, the pH of the 
salt solution shall be adjusted to 4.0 ± 0 .2 by the addition of sulphuric acid and nitric acid in a 2:1 ratio, and 
in the test of the other unit, the pH of the salt solution shall be adjusted to 10.0 ± 0.2 by the addition of sodium 
hydroxide. The temperature within the fog chamber is maintained at  30-35°C).  
 Following these tests, each pressure relief device shall  comply with the requirements of the leak test (   2. 
1.8.), Flow Rate Test (   2. 1.10.) and bench top activation test (   2. 1.9.).  
 2. 1.5.  Vehicle environment test  
 Resistance to degr adation by external exposure to automotive fluids is determined by the following test:  
(a) The inlet and outlet connections of the TPRD are connected or capped in accordance with the manufacturers 
installation instructions. The external surfaces of the TPR D are exposed for 24 hours at 20 ( ±5) C to each of 
the following fluids:  
(i) Sulphuric acid - 19 per cent solution by volume in water;  
(ii) Sodium hydroxide - 25 per cent solution by weight in water;  
(iii) Ammonium nitrate - 28 per cent by weight in water ; and  
(iv) Windshield washer fluid (50 per cent by volume methyl alcohol and water).  
 The fluids are replenished as needed to ensure complete exposure for the duration of the test. A distinct test is 
performed with each of the fluids. One component may be used for exposure to all of the fluids in sequence.  
(b) After exposure to each fluid, the component is wiped off and rinsed with water;  
(c) The component shall not show signs of  physical degradation that could impair the function of the component, 
specific ally: cracking, softening, or swelling. Cosmetic changes such as pitting or staining are not failures. At 
the conclusion of all exposures, the unit(s) shall comply with the requirements of the Leak Test (   2. 1.8.), 
Flow Rate Test (   2. 1.10.) and Bench Top Activation test (   2. 1.9.).  
 2. 1.  Stress corrosion cracking test.  UAE Technical regulation  for FCV  
 For TPRDs containing components made of a copper -based alloy (e.g. brass), one TPRD unit is tested. All copper 
alloy components  exposed to the atmosphere shall be degreased and then continuously exposed for ten days 
to a moist ammonia -air mixture maintained in a glass chamber having a glass cover.  
 Aqueous ammonia having a specific gravity of 0.94 is maintained at the bottom of the glass chamber below 
the sample at a concentration of at least 20 ml per litre of chamber volume. The sample is positioned 35  (±5) 
mm above the aqueous ammonia solution and supported in an inert tray. The moist ammonia -air mixture is 
maintained at atmospheric pressure at 35  (±5) °C. Copper -based alloy compone nts shall not exhibit cracking 
or delaminating due to this test.  
 2. 1.7.  Drop and vibration test  
(a) Six TPRD units are dropped from a height of 2 m at ambient temperature (20 ± 5oC) onto a smooth concrete 
surface. Each sample is allowed to bounce on the concrete surface after the initial impact. One unit is dropped 
in six orientations (opposing directions of 3 orthogonal axes: vertical, lateral and longitudinal). If each of the 
six dropped samples does not show visible exterior damage that indicates that the part is unsuitable for use, it 
shall proceed to step (b);  
(b) Each of the six TPRD units dropped in step (a) and one additional unit not subjected to a drop are mounted in 
a test fixture in accordance with manufacturer’s installation instructions and v ibrated 30 minutes along each 
of the three orthogonal axes (vertical, lateral and longitudinal) at the most severe resonant frequency for each 
axis. The most severe resonant frequencies are determined using an acceleration of 1.5 g and sweeping through 
a sinusoidal frequency range of 10 to 500 Hz within 10 minutes. The resonance frequency is identified by a 
pronounced increase in vibration amplitude. If the resonance frequency is not found in this range, the test shall 
be conducted at  40 Hz. Following this test, each sample shall not show visible exterior damage that indicates 
that the part is unsuitable for use. It shall subsequently comply with the requirements of the Leak Test (   2. 
1.8.), Flow Rate Test (   2. 1.10.) and Bench Top Activation Test (   2.  1.9.).  
 2. 1.8.  Leak test  
A TPRD that has not undergone previous testing  is tested at ambient, high and low temperatures without being 
subjected to other design qualification tests. The unit is held for one hour at each temperature and test pressure 
befor e testing. The three temperature test conditions are:  
(a) Ambient temperature: condition the unit at 20  (±5) °C; test at 5 per cent NWP (+0/ -2MPa) and 150 per cent 
NWP (+2/ -0MPa) ;  
(b) High temperature: condition the unit at 85  °C or higher; test at 5 per cent NWP (+0/ -2MPa) and 150 per cent 
NWP (+2/ -0MPa) ;  
(c) Low temperature: condition the unit at -40°C or lower; test at 5 per cent NWP (+0/ -2MPa) and 100 per cent 
NWP (+2/ -0MPa).   
Additional units undergo leak testing as specified in other tests in    2. 1. with uninterrupted exposure at the 
temperature specified in those tests.  
At all specified test temperatures,  the unit is conditioned for one minute by immersion in a temperature  controlled 
fluid (or equivalent  method ). If no bubbles are observed for th e specified time period, the sample passes the 
test. If bubbles are detected, the  leak rate is measured by an appropriate method. The total hydrogen leak rate 
shall be less than 10 NmL/hr.  
 2. 1.9.  Bench top activation test  
 Two new TPRD units are tested w ithout being subjected to other design qualification tests in order to establish 
a baseline time for activation. Additional pre -tested units (pre -tested according to paras.  2. 1.1.,  2. 1.3.,  2. 
1.4.,  2. 1.5. or  2. 1.7.) undergo bench top activation te sting as specified in other tests in    2. 1.  
(a) The test setup consists of either an oven or chimney which is capable of controlling air temperature and flow 
to achieve 600 (±10)°C in the air surrounding the TPRD. The TPRD unit is not exposed directly to  flame. The 
TPRD unit is mounted in a fixture according to the manufacturer’s installation instructions; the test 
configuration is to be documented;  UAE Technical regulation  for FCV  
 (b) A thermocouple is placed in the oven or chimney to monitor the temperature. The temperature remains wit hin 
the acceptable range for two minutes prior to running the test;  
(c) The pressurized TPRD unit is inserted into the oven or chimney, and the time for the device to activate is 
recorded. Prior to insertion into the oven or chimney, one new (not pre -tested) TPRD unit is pressurized to no 
more than 25 per cent NWP (the pre -tested); TPRD units are pressurized to no more than 25 per cent NWP; 
and one new (not pre -tested) TPRD unit is pressurized to 100 per cent NWP;  
(d) TPRD units previously subjected to othe r tests in    2. 1. shall activate within a period no more than two 
minutes longer than the baseline activation time of the new TPRD unit that was pressurized to up to 25 per 
cent NWP;  
(e) The difference in the activation time of the two TPRD units that ha d not undergone previous testing shall be 
no more than 2 minutes.  
 2. 1.10.  Flow rate test  
(a) Eight TPRD units are tested for flow capacity. The eight units consist of three new TPRD units and one TRPD 
unit from each of the following previous tests: paras .  2. 1.1.,  2. 1.3.,  2. 1.4.,  2. 1.5. and  2. 1.7. ;  
(b) Each TPRD unit is activated according to    2. 1.9. After activation and without cleaning, removal of parts, or 
reconditioning, each TPRD unit is subjected to flow test using hydrogen, air or an i nert gas;  
(c) Flow rate testing is conducted with a gas inlet pressure of 2 (±0.5) MPa. The outlet is at ambient pressure. The 
inlet temperature and pressure are recorded;  
(d) Flow rate is measured with accuracy within ±2 per cent. The lowest measured valu e of the eight pressure relief 
devices shall not be less than 90 per cent of the highest flow value.  
 2. 2. Compressed hydrogen storage qualification performance tests for check valve and shut -off valve  
 Testing shall be performed with hydrogen gas having gas quality compliant with ISO 14687 -2/SAE J2719. 
All tests are performed at ambient temperature 20 ( ±5)°C unless otherwise specified. The check valve and 
shut-off valve qualification performance tests are specified as follows:  
 2. 2.1.  Hydrostatic strengt h test  
 The outlet opening in components is plugged and valve seats or internal blocks are made to assume the open 
position. One unit is tested without being subjected to other design qualification tests in order to establish a 
baseline burst pressure, oth er units are tested as specified in subsequent tests of    2. 2. 
(a) A hydrostatic pressure of 250 per cent NWP (+2/ -0 MPa) is applied to the inlet of the component for three 
minutes. The component is examined to ensure that rupture has not occurred;  
(b) The hydrostatic pressure is then increased at a rate of less than or equal to 1.4 MPa/sec until component failure. 
The hydrostatic pressure at failure is recorded. The failure pressure of previously tested units shall be no less 
than 80 per cent of the fail ure pressure of the baseline, unless the hydrostatic pressure exceeds 400 per cent 
NWP.  
 
 2. 2.2.  Leak test  
One unit that has not undergone previous testing  is tested at ambient, high and low temperatures without being 
subjected to other design qualificat ion tests. The three temperature  test conditions are:  
(a) Ambient temperature: condition the unit at 20  (±5) °C; test at 5 per cent NWP (+0/ -2 MPa) and 150 per cent 
NWP (+2/ -0 MPa) ;  
(b) High temperature: condition the unit at 85  °C or higher ; test at 5 p er cent NWP (+0/ -2 MPa) and 150 per cent 
NWP (+2/ -0 MPa) ;  
(c) Low temperature: condition the unit at -40°C or lower; test at 5 per cent NWP (+0/ -2 MPa) and 100 per cent 
NWP (+2/ -0 MPa).   UAE Technical regulation  for FCV  
 Additional units undergo leak testing as specified in other tests i n    2. 2. with uninterrupted exposure  at the 
temperature s specified in those tests.  
The outlet opening is plugged with the appropriate mating connection and pressurized hydrogen is applied to 
the inlet. At all specified test temperatures, the unit is cond itioned for one minute by immersion in a 
temperature controlled fluid (or equivalent method). If no bubbles are observed for the specified time period, 
the sample passes the test. If bubbles are detected, the leak rate is measured by an appropriate method.  The 
leak rate shall not exceed 10 Nml/hr of hydrogen gas.  
 2. 2.3.  Extreme temperature pressure  cycling test  
(a) The total number of operational cycles is 11,000 for the check valve and 50000 for the shut -off valve. The 
valve unit are installed in a test fixture corresponding to the manufacturer’s specifications for installation. The 
operation of the unit is continuously repeated using hydrogen gas at all specified pressures.  
An operational cycle shall be defined as follows:  
(i) A check valve is connected to a test fixture and 100 per cent NWP (+2/ -0MPa) is applied in six step pulses to 
the check valve inlet with the outlet closed. The pressure is then vented from the check valve inlet. The 
pressure is lowered on the check valve outlet side to  less than  60 per cent NWP prior to the next cycle;  
(ii) A shut -off valve is connected to a test fixture and pressure is applied continuously to the both the inlet and 
outlet sides. An operational cycle consists of one full operation and reset.  
(b) Testing is performed on a unit stabilized at the following temperatures:  
(i) Ambient temperature cycling. The unit undergoes operational (open/closed) cycles at 125 per cent NWP (+2/ -
0 MPa) through 90 per cent of the total cycles with the part stabilized at 20 (±5) °C. At the completion of the 
ambient temperature operational cycles, the unit shall comply with the ambient temperature leak test specified 
in    2. 2.2. ;  
(ii) High temperature cycling. The unit then undergoes operational cycles at 125 per cent NWP (+2/ -0 MPa) 
throu gh 5 per cent of the total operational cycles with the part stabilized at 85°C  or higher . At the completion 
of the 85oC cycles, the unit shall comply with the high temperature (85  °C) leak test specified in    2. 2.2.  
(iii) Low temperature cycling. The un it then undergoes operational cycles at 100 per cent NWP (+2/ -0 MPa) 
through 5 per cent of the total cycles with the part stabilized at -40°C or lower. At the completion of the -
40 °C operational cycles, the unit shall comply with the low temperature ( -40 °C) leak test specified in    2. 
2.2. 
(c) Check valve chatter flow test : Following 11,000 operational cycles and leak tests in    2. 2.3.(b), the check 
valve is subjected to 24  hours of chatter flow at a flow rate that causes the most chatter (valve flutte r). At the 
completion of the test the check valve shall comply with the ambient temperature leak test (   2. 2.2.) and the 
strength test (   2. 2.1.).  
 
 2. 2.4.  Salt corrosion resistance test  
 The component is supported in its normally installed position a nd exposed for 500 hours to a salt spray (fog) 
test as specified in ASTM B117 (standard practice for operating salt spray (fog) apparatus). The temperature 
within the fog chamber is maintained at 30 -35 °C). The saline solution consists of 5  per cent sodium  chloride 
and 95 per cent distilled water, by weight.  
Immediately after the corrosion test, the sample is rinsed and gently cleaned of salt deposits, examined for distortion, 
and then shall comply with the requirements of : 
(a)  The component must now show  signs of physical degradation that could impair the function of the component, 
specifically: cracking, softening or swelling.  Cosmetic changes such as pitting or staining are not failures;  
(b) The ambient temperature leak test (   2. 2.2.);  
(c) The hydro static strength test (   2. 2.1.).  
 2. 2.5.  Vehicle environment test  UAE Technical regulation  for FCV  
  Resistance to degradation by exposure to automotive fluids is determined by the following test.  
(a) The inlet and outlet connections of the valve unit are connected or capped in accordan ce with the 
manufacturers installation instructions. The external surfaces of the valve unit are exposed for 24 hours at 20 
(±5) °C to each of the following fluids:  
(i) Sulphuric acid -19 per cent solution by volume in water;  
(ii) Sodium hydroxide - 25 per  cent solution by weight in water;  
(iii) Ammonium nitrate – 28 per cent by weight in water; and  
(iv) Windshield washer fluid (50 per cent by volume methyl alcohol and water).  
The fluids are replenished as needed to ensure complete exposure for the duration  of the test. A distinct test is 
performed with each of the fluids. One component may be used for exposure to all of the fluids in sequence.  
(b) After exposure to each chemical, the component is wiped off and rinsed with water;  
(c) The component shall not show signs of  physical degradation that could impair the function of the component, 
specifically : cracking, softening, or swelling. Cosmetic changes such as pitting or staining are not failures. At 
the conclusion of all exposures, the unit(s) shall comply with the requirements of the ambient temperature 
leakage test (   2. 2.2.) and hydrostatic strength test (   2. 2.1.).  
 2. 2.  Atmospheric exposure test  
The atmospheric exposure test applies to qualification of check valve and automatic shut -off valves if the component 
has non -metallic materials exposed to the atmosphere during normal operating conditions.  
(a) All non -metallic materials that provide a fuel containing seal, and that are exposed to the atmosphere, for 
which a satisfactory declaration of prop erties is not submitted by the applicant, shall not crack or show visible 
evidence of deterioration after exposure to oxygen for 96 hours at 70°C at 2 MPa in accordance with ASTM 
D572 (standard test method for rubber - deterioration by heat and oxygen) ;  
(b) All elastomers shall demonstrate resistance to ozone by one or more of the following:  
(i) Specification of elastomer compounds with established resistance to ozone;  
(ii) Component testing in accordance with ISO 1431/1, ASTM D1149, or equivalent test meth ods. 
 2. 2.7.  Electrical Tests  
 The electrical tests apply to qualification of the automatic shut -off valve; they do not apply to qualification of 
check valves.  
(a) Abnormal voltage test. The solenoid valve is connected to a variable DC voltage source. The  solenoid valve 
is operated as follows:  
(i) An equilibrium (steady state temperature) hold is established for one hour at 1.5 times the rated voltage;  
(ii) The voltage is increased to two times the rated voltage or 60  volts, whichever is less, and held for  one minute;  
(iii) Any failure shall not result in external leakage, open valve or  unsafe conditions such as smoke, fire or melting.  
The minimum opening voltage at NWP and room temperature shall be less than or equal to 9 V for a 12 V 
system and less than or equal to 18  V for a 24 V system.  
(b) Insulation resistance test. 1,000 V D.C. is applied between the power conductor and the component casing for 
at least two seconds. The minimum allowable resistance for that component is 240 kΩ.  
 2. 2.8.  Vibration test  
 The valve unit is pressurized to its 100 per cent NWP (+2/ -0MPa) with hydrogen, sealed at both ends, and 
vibrated for 30 minutes along each of the three orthogonal axes (vertical, lateral and longitudinal) at the most 
severe resonant frequencies. The most severe resonant frequencies are d etermined by acceleration of 1.5 g 
with a sweep time of 10 minutes within a sinusoidal frequency range of 10 to 40Hz. If the resonance frequency 
is not found in this range the test is conducted at 40Hz. Following this test, each sample shall not show visib le UAE Technical regulation  for FCV  
 exterior damage that indicates that the performance of the part is compromised. At the completion of the test, 
the unit shall comply with the requirements of the ambient temperature leak test specified in    2. 2.2.  
 2. 2.9.  Stress corrosion cracking te st 
For the valve units containing components made of a copper -based alloy (e.g. brass), one valve unit is tested. The 
valve unit is disassembled, all copper -based alloy components are degreased and then the valve unit is 
reassembled before it is continuous ly exposed for ten days to a moist ammonia -air mixture maintained in a 
glass chamber having a glass cover.  
Aqueous ammonia having a specific gravity of 0.94 is maintained at the bottom of the glass chamber below 
the sample at a concentration of at least 20  ml per litre of chamber volume. The sample is positioned 35( ±5) 
mm above the aqueous ammonia solution and supported in an inert tray. The moist ammonia -air mixture is 
maintained at atmospheric pressure at 35( ±5) ºC. Copper -based alloy components shall not  exhibit cracking 
or delaminating due to this test.  
 2. 2.10.  Pre-cooled hydrogen exposure test  
 The valve unit is subjected to pre -cooled hydrogen gas at -40 ºC or lower at a flow rate of 30 g/s at external 
temperature of 20  (±5) ºC for a minimum of three  minutes. The unit is de -pressurized and re -pressurized after 
a two minute hold period. This test is repeated ten times. This test procedure is then repeated for an additional 
ten cycles, except that the hold period is increased to 15 minutes. The unit sha ll then comply with the 
requirements of the ambient temperature leak test specified in    2. 2.2.  
 3.  Test procedures for electrical safety (  5.3.)  
 3.1.  Isolation resistance measurement method  
 3.1.1.  General   
 The isolation resistance for each high vo ltage bus of the vehicle is measured or shall be determined by 
calculating the measurement values of each part or component unit of a high voltage bus (hereinafter referred 
to as the "divided measurement").  
 3.1.2.  Measurement method  
 The isolation resista nce measurement is conducted by selecting an appropriate measurement method from 
among those listed in paras.  3.1.2.1. to  3.1.2.2., depending on the electrical charge of the live parts or the 
isolation resistance.  
 The range of the electrical circuit to be measured is clarified in advance, using electrical circuit diagrams.  
 Moreover, modifications necessary for measuring the isolation resistance may be carried out, such as removal 
of the cover in order to reach the live parts, drawing of measurement line s and change in software.  
 In cases where the measured values are not stable due to the operation of the on -board isolation resistance 
monitoring system, necessary modifications for conducting the measurement may be carried out by stopping 
the operation of  the device concerned or by removing it. Furthermore, when the device is removed, a set of 
drawings will be used to prove that the isolation resistance between the live parts and the electrical chassis 
remains unchanged.  
 Utmost care shall be exercised to avoid short circuit and electric shock since this confirmation might require 
direct operations of the high -voltage circuit.  
 3.1.2.1.   Measurement method using DC voltage from off -vehicle sources  
 3.1.2.1.1.  Measurement instrument  
 An isolation resistance test instrument capable of applying a DC voltage higher than the working voltage of 
the high voltage bus is used.  
 3.1.2.1.2.  Measurement method  
 An insulator resistance test instrument is connected between the live parts and the electrical chassis. The 
isolation resistance is subsequently measured by applying a DC voltage at least half of the working voltage of 
the high voltage bus.  UAE Technical regulation  for FCV  
  If the system has several voltage ranges (e.g. because of boost converter) in conductive connected circuit and 
some of the c omponents cannot withstand the working voltage of the entire circuit, the isolation resistance 
between those components and the electrical chassis can be measured separately by applying their own 
working voltage with those components disconnected.  
 3.1.2.2 . Measurement method using the vehicle’s own REESS as DC voltage source  
 3.1.2.2.1.  Test vehicle conditions  
 The high voltage -bus is energized by the vehicle’s own REESS and/or energy conversion system and the 
voltage level of the REESS and/or energy conve rsion system throughout the test shall be at least the nominal 
operating voltage as specified by the vehicle manufacturer.  
 3.1.2.2.2.  Measurement instrument  
 The voltmeter used in this test shall measure DC values and has an internal resistance of at leas t 10 MΩ.  
 3.1.2.2.3.  Measurement method  
 3.1.2.2.3.1.  First step  
 The voltage is measured as shown in Figure 9 and the high voltage  Bus voltage (Vb) is recorded. Vb shall be 
equal to or greater than the nominal operating voltage of the REESS and/or energy conversion system as 
specified by the vehicle manufacturer.  
Figure 8  
Measurement of Vb, V1, V2  
 
 3.1.2.2.3.2.  Second step  
The voltage (V1) between the negative side of the high voltage bus and the electrical  chassis is measured and 
recorded (see Figure 8) . 
 3.1.2.2.3.3.  Third step  
The voltage (V2) between the positive side of the high voltage bus and the electrical  chassis is measured and 
recorded (see Figure 8).  
 3.1.2.2.3.4.  Fourth step  
Electrical Chassis  
Electrical Chassis  
 
High Voltage Bus  
Energy Conversion  
System Assembly  
REESS Assembly  
V2 
V1 
Vb 
 
  
  
+ 
- 
+ 
- 
 Energy  
Conversion  
REESS 
Traction System  UAE Technical regulation  for FCV  
 If V1 is greater than or equal to V2, a standard known resistance (R o) is inserted between the negative side of 
the high voltage bus and the electrical  chassis. With Ro installed, the voltage (V1’) between the negative side 
of the high voltage bus and the electrical  chassis is measured (see Figure 9). 
The electrical isolat ion (Ri) is calculated according to the following formula:  
Ri = Ro*(Vb/V1’ – Vb/V1) or Ri = Ro*Vb*(1/V1’ – 1/V1)  
The resulting Ri, which is the electrical isolation resistance value (in Ω), is divided by the working voltage of 
the high voltage bus in volt (V):  
Ri Ω / V = Ri Ω / Working voltage (V)  
Figure 9  
Measurement of V1´  
 
If V2 is greater than V1, a standard kno wn resistance (Ro) is inserted between the positive side of the high voltage 
bus and the electrical  chassis. With Ro installed, the voltage (V2’) between the positive side of the high voltage 
bus and the electrical  chassis is measured (see Figure 1 0). The electrical isolation (Ri) is calculated according 
to the formula shown below. This electrical isolation value (in ohms) is divided by the nominal operating 
voltage of the high voltage bus (in volts). The electrical isolation (Ri) is calculated according to  the following 
formula:  
Ri = Ro*(Vb/V2’ – Vb/V2) or Ri = Ro*Vb*(1/V2’ – 1/V2)  
The resulting Ri, which is the electrical isolation resistance value (in Ω), is divided by the working voltage of 
the high voltage bus in volts (V).  
Ri Ω / V = Ri Ω / Working vol tage 
 
 
Figure 10  
Measurement of V2  
Electrical Chassis  
Electrical Chassis  
 
High Voltage Bus  
Energy Conversion  
System Assembly  
REESS Assembly  
V1´ 
Vb 
 
  
  
+ 
- 
+ 
- 
 Energy  
Conversion  
 System  
REESS 
Traction System  
R0 UAE Technical regulation  for FCV  
  
 3.1.2.2.3.5.  Fifth step  
The electrical isolation value Ri (in ohms) divided by the working voltage of the high voltage bus (in volts) 
results in the isolation resistance (in ohms/volt).  
(Note 1 : The standard known resi stance Ro (in ohms) is the value of the minimum required isolation resistance (in 
ohms/V) multiplied by the working voltage of the vehicle plus/minus 20 per cent (in volts). Ro is not required to be 
precisely this value since the equations are valid for an y Ro; however, a Ro value in this range should provide good 
resolution for the voltage measurements.)  
 3.2. Confirmation Method for Functions of On -board Isolation Resistance Monitoring System  
The function of the on -board isolation resistance monitoring sy stem is confirmed by the following method or 
a method equivalent to it.  
A resistor is inserted that does not cause the isolation resistance between the terminal being monitored and the 
electrical chassis to drop below the minimum required isolation resista nce value. The warning signal shall be 
activated.  
 3.3. Protection against direct contacts of parts under voltage  
 3.3.1.  Access probes  
Access probes to verify the protection of persons against access to live parts are given in Table 3.  
 3.3.2.  Test condit ions 
The access probe is pushed against any openings of the enclosure with the force specified in Table 3. If it 
partly or fully penetrates, it is placed in every possible position, but in no case shall the stop face fully penetrate 
through the opening.  
Internal electrical protection barriers are considered part of the enclosure.  
A low -voltage supply (of not less than 40 V and not more than 50 V) in series with a suitable lamp is connected, 
if necessary, between the probe and live parts inside the electrica l protection barrier or enclosure.  
The signal -circuit method is also applied to the moving live parts of high voltage equipment.  
Internal moving parts may be operated slowly, where this is possible.  
 3.3.3.  Acceptance conditions  
The access probe shall  not touch live parts.  
Electrical Chassis  
Electrical Chass is 
 
High Voltage Bus  
Energy Conversion  
System Assembly  
REESS Assembly  
V2' 
 
 
 
+ 
- 
+ 
- 
 Energy  
Conversion  
 System  
REESS 
 Traction System  
R0 UAE Technical regulation  for FCV  
 If this requirement is verified by a signal circuit between the probe and live parts, the lamp shall not light.  
In the case of the test for IPXXB, the jointed test finger may penetrate to its 80 mm length, but the stop face 
(diameter 50 m m x 20 mm) shall not pass through the opening. Starting from the straight position, both joints of 
the test finger are successively bent through an angle of up to 90 degree with respect to the axis of the adjoining 
section of the finger and are placed in e very possible position.  
In case of the tests for IPXXD, the access probe may penetrate to its full length, but the stop face shall not 
fully penetrate through the opening.  
Table 3  
Access probes for the tests for protection of persons against access to haza rdous parts  
 
Figure 11  
Jointed Test Fingers  
 
Material: metal, except where otherwise specified  
Linear dimensions in millimetres  
UAE Technical regulation  for FCV  
 Tolerances on dimensions without specific tolerance:  
on angles, 0/10'  
on linear dimensions:  
up to 25 mm: 0/ -0.05 
over 25 mm: ±0.2 
Both joints shall permit movement in the same plane and the same direction through an angle of 90° with a 0 
to +10° tolerance.  
 3.4. Test Method for Measuring Electric Resistance  
Test method using a resistance tester.  
The resistance tester is connected  to the measuring points (typically, electrical chassis and electro conductive 
enclosure/electrical protection barrier) and the resistance is measured using a resistance tester that meets the 
specification that follows ; 
Resistance tester: Measurement curre nt at least 0.2 A  
Resolution 0.01 Ω or less  
The resistance R shall be less than 0.1 ohm.  
Test method using D.C. power supply, voltmeter and ammeter.  
Example of the test method using D.C. power supply, voltmeter and ammeter is shown below.  
Figure  12 
Connection to Barrier/En closure  
 
 
 
 
 
 
 
 
 
Test Procedure  
The D.C. power supply, voltmeter and ammeter are connected to the measuring points (Typically, electrical chassis 
and electro conductive enclosure/electrical protection barrier).  
The voltage of the D.C. power supply is adjus ted so that the current flow becomes more than 0.2 A.  
The current "I " and the voltage "V " are measured.  
The resistance "R " is calculated according to the following formula:  
R = V / I  
The resistance R shall be less than 0.1 ohm . 
 
D.C.  
Power 
Supply  
A 
V 
Connection to  
Electrical Chassis  
 
I 
V 
R 
Barrier/Enclosure  
Electrical Chassis  UAE Technical regulation  for FCV  
 Note : If lead wires are  used for voltage and current measurement, each lead wire shall be independently connected to 
the electrical protection barrier/enclosure/electrical chassis. Terminal can be common for voltage 
measurement and current measurement.  
 
 
 
 
 
 
 
 
 
 
 3.5.  Test Con ditions and Test Procedure regarding Post Crash  
 3.5.1.  Test Conditions  
 3.5.1.1.  General  
 The test conditions specified in paragraphs  3.5.1.2 to  3.5.1.4. are used.  
 Where a range is specified, the vehicle shall be capable of meeting the requirements at all points within the 
range.  
 3.5.1.2.  Electrical power train adjustment  
 3.5.1.2.1.  The REESS may be at any state of charge, which allows the normal operation of the power train as 
recommended by the manufacturer.  
 3.5.1.2.2.  The electrical power train sh all be energized with or without the operation of the original electrical 
energy sources (e.g. engine -generator, REESS or electric energy conversion system), however:  
 3.5.1.2.2.1. It is permissible to perform the test with all or parts of the electrical p ower train not being energized 
insofar as there is no negative influence on the test result. For parts of the electrical power train not energized, 
the protection against electric shock shall be proved by either physical protection or isolation resistance and 
appropriate additional evidence.  
 3.5.1.2.2.2. If the power train is not energized and an automatic disconnect is provided, it is permissible to perform 
the test with the automatic disconnect being triggered. In this case it shall be demonstrated that the automatic 
disconnect  would have operated during the impact test. This includes the automatic activation signal as well 
as the conductive separation considering the conditions as seen during the impact.  
 3.5.1.3.  Contracting parties may allow modificati ons to the fuel system so that an appropriate amount of fuel can be 
used to run the engine or the electrical energy conversion system.  
 3.5.1.4.  The vehicle conditions other than specified in paras.  3.5.1.1. to  3.5.1.3. are in the crash test protocols of the 
contracting parties.  
 3.5.2.  Test Procedures for the protection of the occupants of vehicles operating on electrical power from high voltage 
and electrolyte spillage  
 This section describes test procedures to  demonstrate compliance with the electrical safety requirements of   
5.3.2.  
 Before the vehicle impact test conducted, the high voltage bus voltage (Vb) (see Figure 1 3) is measured and 
recorded to confirm that it is within the operating voltage of the vehi cle as specified by the vehicle 
manufacturer.  
 3.5.2.1.  Test setup and equipment  
 If a high voltage disconnect function is used, measurements are taken from both sides of the device performing 
the disconnect function.  
  
Barrier/Enclosure/  
Electrical chassis  
 Lead Wires  
Bolt  
Terminal  
Lead wires shall be independent for current 
measurement and voltage measurement. 
Terminal can be common.  UAE Technical regulation  for FCV  
  However, if the high voltage discon nect is integral to the REESS or the energy conversion system and the 
high-voltage bus of the REESS or the energy conversion system is protected according to protection degree 
IPXXB following the impact test, measurements may only be taken between the devi ce performing the 
disconnect function and electrical loads.  
 The voltmeter used in this test measures DC values and have an internal resistance of at least 10 MΩ.  
 3.5.2.2.  The following instructions may be used if voltage is measured.  
 After the impact te st, determine the high voltage bus voltages (Vb, V1, V2) (see figure 13).  
 The voltage measurement is made not earlier than 5 seconds, but not later than 60 seconds after the impact.  
 This procedure is not applicable if the test is performed under the cond ition where the electric power train is 
not energized.  
Figure 13  
Measurement  of Vb, V1, V2  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 3.5.2.3.  Isolation resistance   
 See    3.1.2. "Measurement method"  
 All measurements for calculating voltage(s) and electrical isolation are  made after a minimum of 5 seconds 
after the impact.  
 For example, megohmmeter or oscilloscope measurements are an appropriate alternative to the procedure 
described above for measuring isolation resistance. In this case it may be necessary to deactivate t he on -board 
isolation resistance monitoring system.  
 3.5.2.4.  Physical Protection  
 Following the vehicle crash test, any parts surrounding the high voltage components are opened, disassembled 
or removed without the use of tools. All remaining surrounding p arts shall be considered part of the physical 
protection.  
  The jointed test finger described in    3.3. is inserted into any gaps or openings of the physical protection with 
a test force of  10 N ± 10 per cent for electrical safety assessment. If partial o r full penetration into the physical 
- - 
 
High Voltage Bus  
Energy Conversion  
System Assembly  
REESS Assembly  
V2 
V1 
 
Vb 
 
 
 
+ 
- 
+ 
- 
Energy  
Conversion  
System  
Traction System  
Electrical Chassis  
REESS UAE Technical regulation  for FCV  
 protection by the Jointed Test Finger occurs, the Jointed Test Finger shall be placed in every position as 
specified below.  
 Starting from the straight position, both joints of the test finger are rotated progressively through an angle of 
up to 90 degrees with respect to the axis of the adjoining section of the finger and are placed in every possible 
position.  
 Internal electrical protection barriers are considered part of the enclosure  
 If appropriate, a low -voltage sup ply (of not less than 40 V and not more than 50 V) in series with a suitable 
lamp is connected between the Jointed Test Finger and high voltage live parts inside the electrical protection 
barrier or enclosure  
 3.5.2.5.  Acceptance conditions  
 The requiremen ts of   5.3.2.2.3. are met if the jointed test finger described in    3.3. is unable to contact high 
voltage live parts.  
 If necessary a mirror or a fibre scope may be used in order to inspect whether the jointed test finger touches 
the high voltage buses.  
 If this requirement is verified by a signal circuit between the jointed test finger and high voltage live parts, the 
lamp shall not light.  
 3.5.2.   Electrolyte spillage  
 Appropriate coating shall be applied, if necessary, to the physical protection in o rder to confirm any electrolyte 
leakage from the REESS after the impact test.  
 Unless the manufacturer provides the means to differentiate among the leakage of different liquids, all liquid 
leakage is considered as an electrolyte.  
 3.5.2.7.  REESS retention  
 Compliance shall be determined by visual inspection  
 
 
 
 
 
 
 
 
 
 
 
 
 
ANEX  2     -   International  Reference Standards  UAE Technical regulation  for FCV  
  1. Vehicle fuel system  
 -   ISO 17268 – Compressed hydrogen surface vehicle refuelling connection devices;  
-  ISO 23273 -1 – Fuel cell road vehicles – Safety specifications – Part 1: Vehicle functional safety;  
-  ISO 232 73-2 – Fuel cell road vehicles – Safety specifications – Part 2: Protection against 
hydrogen hazards for vehicles fuelled with compressed hydrogen;  
-  ISO 14687 -2 – Hydrogen Fuel – Product Specification – Part 2: Proton exchange membrane 
(PEM) fuel cell ap plications for road vehicles;  
 2. Storage system  
 -  United States – FMVSS 304 - Compressed Natural Gas fuel Container Integrity;  
-  European Union – Regulation 406/2010 implementing EC Regulation 79/2009;  
 -  ISO 13985:2006 – Liquid Hydrogen – Land Vehicle Fuel Tanks;  
-  ISO 15869:2009 – Gaseous Hydrogen and Hydrogen Blends – Land Vehicle Fuel Tanks (Technical 
Specification) ;  
 3. Electric safety  
- ECE – Regulation 100 - Uniform Provisions Concerning the Approval of Battery 
Electric Vehicles with Regard to Specific Requirements for the Construction and 
Functional Safety;  
- United States – FMVSS 305 - Electric -Powered Vehicles: Elec trolyte Spillage and 
Electrical Shock Protection.  
- ISO 23273 -3 – Fuel cell road vehicles — Safety specifications – Part 3: Protection of 
persons against electric shock;  
- ISO 19880 -3:2018 Gaseous hydro gen -- Fuelling stations -- Part 3: Valves  
- ISO/TS 19880 -1:2016 Gaseous hydrogen -- Fuelling stations -- Part 1: General 
requirements