UN R135 — Supplement 3 to the 00 series of amendments

Paragraph 2.3. now says the compressed hydrogen storage system (CHSS) is composed of “a container, container attachments (if any), and all primary closure devices”. These closure devices are those “required to isolate the stored hydrogen from the remainder of the fuel system and the environment”. Before, the CHSS was composed of “a pressurized container, pressure relief devices (PRDs) and shut off device”. The CHSS is now designed to store “compressed hydrogen fuel”, where before it was designed to store “hydrogen fuel”.

Paragraph 2.4. now defines the container as “the pressure-bearing component on the vehicle” that stores the primary volume of hydrogen fuel. The container stores this fuel “in a single chamber or in multiple permanently interconnected chambers”. Before, the container was “the component within the hydrogen storage system” that stores the primary volume of hydrogen fuel. New paragraph 2.4.1. defines “Container Attachments” as non-pressure bearing parts attached to the container that provide additional support and/or protection to the container. These parts “may be only temporarily removed for maintenance and/or inspection only with the use of tools”.

Paragraph 2.10. now says that hydrogen fuel for the vehicles is specified in ISO 14687:2019 and SAE J2719_202003. Before, it said that hydrogen fuel for passenger vehicles is specified in ISO 14687-2:2012 and SAE J2719 (Sep 2011 Revision).

Paragraph 2.14. now reads only “Passenger compartment”, and new paragraphs 2.14.1. and 2.14.2. give two definitions. Paragraph 2.14.1. defines “Passenger compartment with regard to occupant protection” with the boundaries that paragraph 2.14. gave before. Paragraph 2.14.2. defines “Passenger compartment for hydrogen safety assessment”. This space is bounded by the roof, floor, side walls, doors, outside glazing, front bulkhead and rear bulkhead, or back door.

Paragraph 2.20. defines the shut-off valve (for hydrogen-fuelled vehicles) as a valve between the container and the vehicle fuel system. The valve must now default to the “closed” position when not connected to a power source. Before, the definition said the valve “can be automatically activated” and “defaults” to the “closed” position when not connected to a power source. It also said “storage container” where it now says “container”.

The definition of “Vehicle type” in paragraph 2.26. now says: “in so far as they have an adverse effect on the result of the impact test prescribed in this Regulation”. The words “in so far as they may be considered to have a negative effect on the results of a vehicle‑to‑pole side impact test” are deleted. The deleted words go on: “conducted in accordance with Annex 3 of this Regulation”.

In Annex 6, “Enclosed spaces” now means the special volumes within the vehicle (or the vehicle outline across openings) that are external to the hydrogen system. The hydrogen system in this definition now lists the “internal combustion engine (ICE)” next to the storage system, fuel cell system and fuel flow management system. The definition no longer refers to the housings (if any) of the hydrogen system, and no longer gives examples such as the passenger compartment. Paragraph 3.1.4. now says that the main stop valve and shut-off valves are “in the normal driving condition kept open” immediately before the impact. In the formulas for ρo' and ρf' in paragraphs 4.2. and 4.3., the constant is now 1.07 instead of 0.5789. These formulas are part of the calculation of the initial and final mass of hydrogen in the storage system.