The fire safety of infrastructure facilities for hydrogen-powered vehicles

Introduction. The article offers an analytical review of domestic and foreign publications on the fire safety of hydrogen refueling stations and garages for hydrogen-powered vehicles. General characteristics of the fire hazard of infrastructure facilities for hydrogen-powered vehicles. The authors offer the general characteristic of a specific fire hazard from facilities using compressed and liquid hydrogen. Hydrogen refueling stations. Refueling stations using compressed and liquid hydrogen were considered in the article. It was found that compressors are the most hazardous items installed at refueling stations; therefore, the value of potential risks, arising in the area of a refueling station, exceeds 10–4 year–1. Experiments, simulating accidents at hydrogen refueling stations, are described. According to the authors, the minimal distance between the compressor and facilities located outside the station area should exceed 50 m. Garages for hydrogen-powered vehicles. Features of the fire safety of garages for hydrogen-powered vehicles were analyzed. The authors have found that the overpressure inside a small garage (an individual garage) can reach 55 kPa in case of a jet flame caused by the release of hydrogen through the safety valves of fuel tanks. The overpressure of a hydrogen jet can reach 10 kPa in case of the unignited release of hydrogen. High pressure values that accompany the jet formation are triggered by the high normal burning velocity of hydrogen that boosts the velocity of heat release in the flame front, exceeding the same value for flares of hydrocarbon gases. Therefore, requirements, applicable to storage premises designated for vehicles powered by hydrocarbon fuel, may be erroneously extended to garages for hydrogen-powered vehicles (pursuant to NFPA 2). Conclusions. The results of this analysis can be contributed to regulatory documents to be developed in the area of fire safety of infrastructure facilities for hydrogen-powered vehicles.