China's Ministry of Industry and Information Technology (MIIT) has opened public consultation on a new mandatory national safety standard for fuel-cell electric vehicles, according to IThome. The draft, published on September 9, introduces a cap on hydrogen emission rates and a mandatory refueling communication function for high-pressure hydrogen storage systems.
The proposed standard, titled "Fuel Cell Electric Vehicles – Safety Requirements," updates a previous recommended standard to address safety risks that have emerged as fuel-cell commercial vehicles and medium- and heavy-duty trucks are deployed in large numbers across demonstration city clusters. These vehicles now operate on highways, urban roads, tunnels, and parking lots, exposing them to more complex driving conditions.
Hydrogen emission cap for tunnel safety
One of the key additions is a requirement that the hydrogen emission rate of a fuel-cell system must not exceed 8.0%. The hydrogen emission rate represents the proportion of hydrogen that is not used in the electrochemical reaction and is released through the exhaust during operation. The draft standard's drafting team determined the value through theoretical calculations for tunnel models and verified that current mainstream vehicles can meet the requirement.
The new cap is intended to ensure safety in semi-enclosed spaces such as tunnels, where hydrogen accumulation could pose a risk. Hydrogen molecules have strong permeability and a wide explosive range, and onboard high-pressure hydrogen storage systems carry inherent risks of leakage, pressure release, and gas accumulation.
Mandatory refueling communication for 70MPa systems
The draft also makes it mandatory for fuel-cell vehicles equipped with 70MPa hydrogen storage tanks to have a refueling communication function. This feature enables communication between the vehicle and the hydrogen refueling station, allowing for precise and controlled hydrogen filling.
According to IThome, the requirement addresses issues found in real-world operation. Without communication during refueling, filling efficiency drops significantly, and the process can cause localized overheating in the storage tank—a problem especially pronounced in Type IV hydrogen tanks. Over time, repeated non-communicative refueling can degrade tank performance, shorten its service life, and compromise the safety of the high-pressure hydrogen storage system.
The draft standard reflects the industry's shift toward 70MPa high-pressure hydrogen storage, which is gradually being adopted in newer vehicles. The previous recommended standard lagged behind these technological developments, lacking hard constraints for certain operating conditions.
The public comment period is part of China's broader effort to establish minimum safety thresholds as fuel-cell electric vehicles move toward large-scale commercialization. The standard, once finalized, will set mandatory safety requirements for all fuel-cell electric vehicles sold in China.
Based on reporting by IT之家. Edited and published in English by geisou.
