Working Party 29
UN - Global Regulations on Pollution and the Environment


United Nations


Working Party 29 - Global Regulations on Pollution and the Environment
Global Technical Regulations (GTR)
Hydrogen Vehicles - Liquid Hydrogen, Gaseous Hydrogen


UNECE’s World Forum for Harmonization of Vehicle Regulations (WP.29) adopted on 27 June 2013 a United Nations Global Technical Regulation (UN GTR) governing the safety of hydrogen and fuel cell-powered vehicles (HFCVs). This new UN GTR represents the first international legislation in this field.

HFCVs can use either internal combustion engines fuelled by liquefied hydrogen or fuel-cells fuelled by compressed gaseous hydrogen. Hydrogen fuelled vehicles are typically powered by fuel-cell power systems which generate electric power electrochemically. The UN GTR specifies provisions to ensure that such vehicles attain the same safety level as conventional gasoline vehicles.

The new UN GTR specifies safety-related performance requirements for HFCVs, aiming at protecting occupants from fire or explosion of the hydrogen on-board containers. It also includes requirements to prevent electric shock to occupants or first responders in case of a crash.

The high-voltage safety provisions adopted today for HFCVs can be used in the future UN GTR that the World Forum is preparing to encompass all types of electric vehicles (irrespective of the technology used to generate power).

The adoption of this new UN GTR could help foster interest in HFCVs, in view of the potential benefits of this technology with regards to:

Energy efficiency. Thanks to the elimination of the engine’s mobile parts, such as pistons, HFCVs generally achieve between 40–60% energy efficiency, compared to 25% in conventional internal combustion engine vehicles.

Emissions reduction. HFCVs do not produce harmful tailpipe emissions. They could thus help reduce vehicles’ emissions of harmful gaseous pollutants, provided some bottlenecks are overcome. These include: (i) the safe and economically-sound mass production of hydrogen from other sources than fossil fuels, (ii) the development of refuelling infrastructures and (iii) safe mass-scale transportation of hydrogen.

The text of the UN GTR, which takes into account existing standards and regulations from Canada, China, the European Union, Japan, Korea and the United States, is available at:


Safety regulations for hydrogen vehicles. Government level activity. US represented by the US Department of Transportation.


Global Technical Regulations (GTR) is:

1.     Process for developing and promulgating motor vehicle safety standards and/or regulations for motor vehicles by participating countries, and

2.     The standards and/or regulations emanating from that process.


The GTR concept was created by the 1998 UN Global Agreement to harmonize, internationally, vehicle regulations and make vehicle parts produced under GTR’s available for sale in any country. The signatories to the Global Agreement include:

   · United States

   · European Community

   · Canada

   · Japan

   · Germany

   · Russian Federation

   · Republic of Korea

   · Peoples Republic of China


(efforts are being devoted to establish one or more GTR’s that address safety requirements for hydrogen powered fuel cell vehicles) 

The World Forum for Harmonization of Vehicle Regulations of the United Nations Economic Commission for Europe (UN/ECE/WP29) has the lead role in the global harmonization of automotive regulations - focusing on vehicles at the time of manufacturing.



I. Background

1. The Informal Working Group (IWG) on Hydrogen and Fuel Cell Vehicles - Sub group safety (HFCV-SGS) was set up in 2007. The original schedule and scope were described in ECE/TRANS/WP.29/AC.3/17. This document outlines the HFCV-SGS activities and their timeframes divided into two phases. The IWG submitted the global technical regulation (gtr) on Hydrogen and Fuel Cell Vehicle and it was adopted by the Working Party on Passive Safety (GRSP) as well as established by the World Forum for Harmonization of Vehicle Regulations (WP.29) and the Executive Committee of the 1998 Agreement (AC.3) in June 2013.

2. After the establishment in the Global Registry as gtr No. 13 in June 2013, the provisions were transposed into UN Regulation No 134 annexed to the 1958 Agreement.



II. Proposal

3. An extension of the mandate for the HFCV-SGS IWG, sponsored by the European Union, Japan and Republic of Korea, shall tackle the development of the remaining issues. Phase 2 activities should be started immediately after the endorsement of this authorization by WP.29 and AC.3 at their March 2017 sessions.

4. Since hydrogen fuelled vehicles and fuel cell technologies are in early stages of development of commercial deployment, it is expected that revisions to these requirements may be suggested by an extended time of on-road experience and technical evaluations. It is further expected that with additional experience or additional time for fuller technical consideration, the requirements presented as optional requirements in the gtr (LHSS Section G of the preamble) could be adopted as requirements with appropriate modifications.

5. Scope of work in Phase 2 should cover: (a) Original items described in ECE/TRANS/WP.29/AC.3/17 shall be kept; (b) Potential scope revision to address additional vehicle classes; (c) Requirements for material compatibility and hydrogen embrittlement; (d) Requirements for the fuelling receptacle; (e) Evaluation of performance-based test for long-term stress rupture proposed in Phase 1; (f) Consideration of research results reported after completion of Phase 1 – specifically research related to electrical safety, hydrogen storage systems, and post-crash safety; (g) Consideration of 200 per cent Nominal Working Pressure (NWP) or lower as the minimum burst requirement; (h) Consider Safety guard system for the case of isolation resistance breakdown.

6. In addition, the following test procedure will be considered for long-term stress rupture: (a) Three containers made from the new material (e.g. a composite fibre reinforced polymer) shall be burst; the burst pressures shall be within ±10 per cent of the midpoint, BPo, of the intended application. Then, ECE/TRANS/WP.29/2017/56 3 (i) Three containers shall be held at > 80 per cent BPo and at 65 (±5) °C; they shall not rupture within 100 hrs; the time to rupture shall be recorded; (ii) Three containers shall be held at > 75 per cent BPo and at 65 (±5) °C; they shall not rupture within 1000hrs; the time to rupture shall be recorded; (iii) Three containers shall be held at > 70 per cent BPo and at 65 (±5) °C; they shall not rupture within one year; (iv) The test shall be discontinued after one year. Each container that has not ruptured within the one year test period undergoes a burst test, and the burst pressure is recorded. (b) The container diameter shall be > 50 per cent of the diameter of intended application and of comparable construction. The tank may have a filling (to reduce interior volume) if >99 per cent of the interior surface area remains exposed; (c) Containers constructed of carbon fibre composites and/or metal alloys are excused from this test; (d) Containers constructed of glass fibre composites that have an initial burst pressure > 350 per cent NWP are excused from this test, in which case BPmin = 350 per cent NWP shall be applied in paragraph (Baseline Initial Burst Pressure); (e) There are carbon fibre containers that use glass fibre as the protective layer, and some of these containers contribute about 2 per cent of rise in burst pressure. In this case, it shall be demonstrated, by calculation, etc., that the pressure double the maximum filling pressure or above can be ensured by carbon fibre excluding glass fibre. If it can be demonstrated that the rise in burst pressure due to the glass fibre protective layer is 2 per cent or below and if the burst pressure is 225 per cent NWP x 1.02 = 230 per cent NWP or more, the said calculation may be omitted.

III. Timeline

7. The work of the IWG on HFCV-SGS Phase 2 should be completed by 2020. The work may continue until the end of 2020 without a formal modification of this mandate, unless otherwise needed due to circumstances.

8. A prolongation and extension of the mandate of the IWG on HFCV-SGS may be considered by GRSP in due time.









Christoff Albus