ANNEX V U.K. Applicable test procedures for hydrogen components, other than containers, designed to use compressed (gaseous) hydrogen

	TYPE OF TEST
HYDROGEN COMPONENT	Material tests	Corrosion resistance test	Endurance test	Pressure cycle test	Internal leakage test	External leakage test
Pressure relief devices
Automatic valves
Manual valves
Non-return valves
Pressure relief valves
Heat exchangers
Refuelling connections or receptacles
Pressure regulators
Sensors for hydrogen systems
Flexible fuel lines
Fittings
Hydrogen filters
Removable storage system connectors

Subject to specific requirements for any of the hydrogen components, the test procedures to be applied for the type-approval of hydrogen components, other than containers, designed to use compressed (gaseous) hydrogen must include:

1. Material tests: U.K.

1.1.

Hydrogen compatibility test set out in point (j) of Annex III.

1.2.

Ageing test: the purpose of the test is to check whether the non-metallic material used in a hydrogen component can withstand ageing. No visible cracking of the test samples is allowed.

1.3.

Ozone compatibility test: the purpose of the test is to check whether the elastomer material of a hydrogen component is compatible with ozone exposure. No visible cracking of the test samples is allowed.

2. Corrosion resistance test set out in point (e) of Annex III. U.K.

3. Endurance test set out in point (c) of Annex III. U.K.

4. Pressure cycle test set out in point (i) of Annex III. The hydrogen components must not show visible signs of deformation or extrusion and must fulfil the requirements of the internal and external leakage tests. U.K.

5. Internal leakage test: the purpose of the test is to provide evidence that the specified hydrogen components are free from internal leakage. In order to prove this, the hydrogen components are pressurised under different temperature conditions and observed for leakage. The hydrogen components must stay bubble free and must not leak internally at a higher rate than a specified number. U.K.

6. External leakage test set out in point (b) of Annex III. U.K.