Gas Station Research

Investigation of the Potential for Wireless Phones to Cause Explosions at Gas Stations

Executive Summary


In early 1999, a number of reports were circulated in the news media and on the Internet suggesting that cell phones could cause a fire or explosion if used at gas stations. Although the reports were speculative and unconfirmed, the issue gained impetus when warning labels began to appear at service stations. In response to these events, this study was initiated to define and investigate the extent of the problem, to determine whether the allegations were founded, and to make recommendations as to what actions, if any, should be taken. The cell phone – gas station issue is centered on claims that the cell phone battery could spark and ignite gas fumes, or that the electronic impulses or electromagnetic (RF) waves emitted by the phones might trigger fire and/or explosions of gas fumes. These claims appear to be supported by some cell phone manufacturers, who print warnings in their cell phone instruction manuals against using the phones in areas with “potentially explosive atmospheres” such as gas stations. However, the warnings were apparently issued in response to an outdated United Kingdom regulation from a time when phones operated at powers up to 20 watts, as opposed to the typical power of 0.6 watts today. Various experts have discounted the cell phone’s RF emissions as an ignition source, since the maximum output power of most phones currently in use makes it highly unlikely that the RF could induce sufficient power to ignite gas vapors. Hence, RF emissions can be eliminated as a potential hazard, and the problem can be reduced to examining the potential for the use or misuse of a cell phone battery to cause an explosion. Calculation of the probability of an explosion at a gas station due to cell phone use was beyond the scope of this study. However, a subjective assessment of the potential for a cell phone to cause an explosion was made, based on historical evidence and expert opinion. To add some perspective, comparison was made against the chances that an explosion could occur due to other sources. A matrix was developed that contains subjective ratings indicating the probability that a fire or explosion would occur under specified conditions. The matrix shows the fire/ explosion probability from cell phones to be negligible. To conclude, research into the cell phone – gas station issue provided virtually no evidence to suggest that cell phones pose a hazard at gas stations. In fact, there has never been a confirmed incident implicating a cell phone at a gas station anywhere in the world. While it may be theoretically possible for a spark from a cell phone battery to ignite gas vapor under very precise conditions, the historical evidence does not support the need for further research. Until there is evidence to the contrary, we suggest that no further action be initiated in this regard, and that no recommendations for further action are required of the wireless phone or petroleum industries. 


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