Analyses of LPG Dispersion During Its Accidental Release in Enclosed Car Parks

Despite the fact that LPG (Liquefied Petroleum Gas) is used in a large number of cars, tests have not yet been carried out to ascertain how hazardous can be the release of LPG from the car when parked in enclosed garages. The problem applies to both public and industrial parking areas, especially in Poland, where more than 10% cars are fueled by LPG. The paper describes full scale experiments, which demonstrate conditions that may occur in a garage in the event of accidental LPG release from the car installation. Over the course of the tests, a series of six LPG spillage tests were performed to study emission time and flammable cloud formation depending on the accidental gap diameter. Additionally, to enable the visual observation of the gas dispersion and influence of the ventilation system the experiment was conducted using well visible CO₂ gas cloud, produced from dry ice. The experiments have shown that without ventilation LPG can accumulate on the floor of the enclosed garage for a long time, which generates a high explosive hazard. However, good ventilation (especially jet fan systems) can quickly remove hazardous flammable LPG clouds. Moreover, very important for effective LPG detection is the location of detectors closer to the floor than is currently recommended - at a height of 30 cm.