Hydrogen on track: the EN IEC 63341 series — requirements for fuel cells and hydrogen systems in rolling stock, plus performance test methods
On 29 September 2026 CEN and CENELEC presented the EN IEC 63341 series for hydrogen fuel cells in rolling stock. Its three parts cover the fuel cell power system, the on-board hydrogen fuel system and — in Part 3, dated 2026 — performance test methods that allow systems to be measured and compared consistently.
- EN IEC 63341-1:2025 covers the power system itself: proton exchange membrane (PEM) fuel cell systems running on hydrogen and their integration into vehicles, from trams and metros to regional trains, high-speed trains and locomotives. Safety requirements address hydrogen leakage, fire and explosion risks and electrical hazards, among other things.
- EN IEC 63341-2:2025 covers the on-board hydrogen fuel system: gaseous hydrogen storage, fuel lines, pressure management, fuelling interfaces, monitoring and control, ventilation and emergency protection. Risk assessment, leak detection and safe pressure relief are central elements.
- EN IEC 63341-3:2026 sets out performance test methods: output power, electrical efficiency, hydrogen consumption, start-up and shutdown, dynamic operation, and operation at different temperatures, humidity levels and altitudes. It does not set required performance levels — according to its scope, these are agreed between the user and the manufacturer.
- Part 3 applies to electrically propelled rolling stock powered by hydrogen fuel cells; it does not cover hydrogen vehicles with internal combustion engines or reformer-equipped systems. The Estonian edition EVS-EN IEC 63341-3:2026, based on IEC 63341-3:2025, has been valid since 15 January 2026; on the European side the work is led by CENELEC/TC 9X, building on IEC/TC 9 in cooperation with IEC/TC 105 “Fuel cell technologies”.
Source: CEN-CENELEC — Hydrogen on track: new standards support fuel-cell-powered rolling stock (29.09.2026)