24 June 2006

Handphones are Magnets to Lightning?

The article from AFP, published in TODAYonline, caught my attention:

Talking in the rain? It might be a close call

In summary, it is referring to a report in a medical journal that claimed that using a handphone in the open during a storm day can result in a higher chance of being struck by lightning.

I find the report highly questionable, in particular:

The apparent risk from mobile phones comes not from the radiation that it emits but the metal components it contains. As lightning chooses the easiest route to the ground, someone standing up and using the phone (and probably wet from the rain) may well offer the path of least resistance.


What's wrong with the above sentence? Note that we're talking about handphone here. Unless the handphone is somehow connected to the ground (or in technical terms, earthed), I don't see how the presence of the handphone will significantly increase the electric potential on the person. (Even if it is earthed, I don't think it will make very much of a difference; in fact, an earthed handphone may act as a lightning rod and save a person's life if lightning strikes.)

A human body, by itself, is already a conductor. If there's any charge build-up on that person, it's probably more because of himself than the handphone. Similarly, I doubt the electromagnetic radiation from the handphone (which, technically, is extremely low powered) alters much of the electric potential of the person.

Furthermore, they based their reports on three medical cases, and noted that "no similar cases have ever been reported in medical literature". That's a sampling size of three, and this is very few, in my opinion, as compared to the millions who get struck every year.

Instead of asking people not to use handphones in the open during a thunderstorm, I think it'll do much more good to advise them to stay low and get under shelter.

3 comments:

The Negative Man said...

I think the problem lies with either TODAY or AFP itself, rather than the journal report being uncredible or lousy. I first learnt of this journal finding independently from BBC news, and BBC's version appears to be more reasonable.

Basically BBC's version warns of the dangers of using handphones in thunderstorms. However they do not assert that handphones increase the likelihood of being struck by lightning.
Rather, according to BBC, mobile phones increase the likelihood of injury after being struck.

I suppose this may mean that something was lost in one side's news reporting. Anyway you can find the BBC story url below. I can't html the link in the comment box, though. Just cut and paste.

http://news.bbc.co.uk/2/hi/health/5106510.stm

Pandemonium said...

Ah yes! I see... Now that makes sense: the handphone acts as a conductor for electricity to enter a human's body instead passing through the exterior, and therefore using a handphone during a thunderstorm is not advisable. Yeah, that makes sense.

The mis-reporting is both TODAY's and AFP's fault. AFP for writing a flawed story, and TODAY for not verifying before publishing it.

Thanks for the clarification.

Anonymous said...

talking on handphone under umbrella
or talking under a steel shelter will cause you to be struck by lightning.