Road Vehicles—Compressed Gaseous Hydrogen (CGH2) and Hydrogen/Natural Gas Blends Fuel Systems—Part 2: Test Methods (Draft for Comments)

This draft applies to fuel systems of single-fuel, bi-fuel and dual-fuel vehicles using compressed gaseous hydrogen at pressures not exceeding 70 MPa and hydrogen/natural gas blends at pressures not exceeding 35 MPa. It specifies test methods for cylinder installation strength, leakage, functionality and refuelling receptacle installation. Vehicle manufacturers and relevant testing bodies shall conduct verification using the prescribed test gases, environmental conditions, filling quantities, accelerations or static loads, and determine compliance based on cylinder retention, displacement, leakage and functional requirements. Modified from ISO 21266-2:2018, the draft adds test-gas and environmental requirements and adjusts dynamic cylinder-test accelerations, leakage-rate requirements and acceptance criteria.