Beware of Your Phone Charger!

I’m sure people think I’m getting a little obsessive about the Twenty First Century Science syllabus. If you do then this post will confirm your thoughts because I’m returning to it. In my defence I should point out that it is such a wonderful source of dubious science.

Section P5 covers electric circuits and parts of it cover the heating effects of electric currents. Activity AP5.28 covers domestic fires caused by electricity and includes a commentry by Tony Meade, a Fire Safety Officer in South Yorkshire.

Much of it concerns the dangers posed by over-loaded sockets, high current cabling left wound on its drum so that heat cannot dissapate, fuses replace by nails (!), and attempts to by-pass the meter and cannot be argued with. Some, however, seems to be venturing into the area of urban myth. I hesitate to argue fire-safety with a qualified professional but I would not deserve to use the name Kelvin Throop if I was not prepared to challenge authority occasionally so here goes. Tony Meade says:-

“…One that sticks in my mind particularly is one that was started by a telephone charger that was left on. The heat that was built up eventually caused it to melt, which set fire to the carpet, which then went on to set fire to the furnishings of the room…”

I have to say that Mrs Throop is in the habit of leaving her phone charger plugged in (and the television on standby, of which more anon). I have checked it a few times and it does not feel any hotter than its surroundings. It is possible that sensitive temperature probes might record a temperature above ambient but if it is not enough to be felt by touch it is not enough to melt the plastic.

Internet investigation has turned up cases of faulty chargers over-heating (and even one case of a faulty device being prone to explosion!) and I rather suspect it was one such that caused the fire to which Tony Meade refers.

Elsewhere he says:-

“…TV’s have been left on standby because [people are] too lazy to get up and switch it off. The heat that’s generated from that electricity that’s still going to the TV set has been enough to cause fires…”

I can find no confirmed case where this has happened. I have found speculation that dust might get in the vents and catch fire. This might have been true in the case of old technology televisions that had banks of thermionic valves but I do not think it would happen with modern televisions.

In any event, if TVs generate thismuch heat on standby, how much more would they generate in actual use? Given that children (we are told) are watching hours and hours of TV each week, you would expect televisions to be combusting all over the place.

 I cannot help suspecting that Mr Meade has been subconciously influenced by the current wooly thinking that suggests that we can save electricity and the planet by turning equipment off at the wall rather than leaving it on standby. Obviously, if such savings can be made, the current drawn on standby must be huge.

Actually, it is not, and by mixing myth in with good advice, the risk is that the good advice will be ignored. Look how successful lies and exaggeration have been in discouraging children from taking illegal drugs.

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2 Responses to “Beware of Your Phone Charger!”

  1. andrewtaylor Says:

    My SonyEricsson phone charger got recalled, for fear of explosion. I got a new one, but I passed the old one on to a friend who had a similar phone and had lost his charger. He’s still alive, and if it was going to explode, it would do it near him because that’s his luck.

  2. mugsandmoney Says:

    His advice on phone chargers may be obsolete. My new one is much smaller and cooler than my old one – the march of technology?

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