02e39f42_stem_Risks_of_Alternative_Fuel__Background
[Hazard --Event] Vehicleexplosion -- fromfuel system leaks [Consequences] When ignited, a confined natural gas-airmixture can produce pressures of up to800 kPa -- far more than vehicle glass orbody structures can withstand. [Knowledge] One such explosion has occurred, in anarticulated transit bus under repair atHouston Metro. An analysis of fuel gasleakage into the interior of a vehicle isgiven in . "Efflux of Gaseous Hydrogen or Methane Fuels from the Interior of an Automobile," J.M. Arvidson, et al., National Bureau ofStandards report COM-75-10288, 1 March 1975.. [Background] 
Transit buses have fairly large volume enclosed spaces,especially the passenger compartment. If these spaces fillwith a flammable mixture, a significant explosion can occur.
Clean Air Program -- Assesment of the Safety, Health, Environmental and System Risks of Alternative Fuel
Background