I recently bought petrol and noticed a sign that has been seen on garage forecourts - No Mobile Phones. I did search the reasons for these signs and discovered that while there have been lurid reports of terrible accidents caused by mobile phones on garage forecourts, those reports are all false - see http://www.snopes.com/autos/hazards/gasvapor.asp
To summarize that page: the American Petroleum Institute said "we can find no evidence of someone using a cellphone causing any kind of accident, no matter how small, at a gas station anywhere in the world", and nobody has ever demonstrated that an accident of any kind is even theoretically possible. The lurid tales that suggest otherwise are purely urban legends. There are circumstances where mobile phone use is inadvisable, for instance they shouldn't be used while driving, because they are a distraction, and they should be switched off in hospital operating theatres because they can interfere with delicate electronic equipment there, and in cinemas and at live stage events they can be a nuisance; but none of those reasons were applicable on this particular garage forecourt.
In short, there was no reason for any such sign. I mentioned this to the person who served me, and I added that there was more chance of causing a spark by dropping the phone (i.e. while fumbling to switch it off, in order to ensure it wouldn't ring). To my amazement I got the reply "yes, that's why we have the signs".
What next for garage forecourts? No heavy objects and carpet slippers only?
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