Is it true that one must not use a phone when it is lightining ?
Using a cell phone won't increase your chances of being struck by lightning. However, if you are holding a metal object next to your head or chest when you do get struck, you may receive more severe burns or injury. When you get struck by lightning, the energy normally goes over the surface of your skin trying to get to the ground. If you are wearing metal or other conductive objects, they will absorb a lot of electrical energy and become extremely hot or cause arcing.
edit: I just realized you didn't specify cell phones. if you are referring to a hard line home phone the situation may be different. If your house is struck by lightning, the copper wires of the phone line may conduct the energy through the house. If you are holding the phone when this happens, you could be come a path for the lighting to get to ground. I believe the Mythbusters http://en.wikipedia.org/wiki/MythBusters_(2005_season)#Phone_in_a_Thunderstorm" and found that you could in fact be electrocuted using a phone when the line is struck by lightning.
Welcome to the PF. I think you must be asking about "land line" phones that are connected by wires to the Central Office. According to this article (found with a simple Google search), it's probably not a good idea to use your land line phone during a lightning storm:
Using cell phones is not a problem, as long as your reception is okay.
You probably have as much chance at getting struck by lightning on a land line phone as you do in getting struck while walking from the supermarket to your car.
I wouldn't lose sleep over it.
Also, cordless phones that interact with a wall unit connected to a land-line is okay. It is only when your phone is physically connected by wire to the base and then the wall (a corded land-line). Does anyone even use corded land-line phones anymore?
Well - even with land lines there shouldn't be a problem, unless you live in rural area in USA in a house with obsolete phone set.
- International ITU-T telephone standards (Americans have their own, not so restrictive), set very strong safety standards on voltage shock through the line - appropriate surge fuses must be installed not only in your phone, but also on the entry to the building, and the phone set itself must be properly insulated and grounded;
- In Europe overhead telephone lines got replaced by those dug into ground even in the rural areas quite a long time ago, so some voltage may get induced only on a short part of the line within your house;
- very few people use phones connected on cable: usually your land-line phone terminates on your home basestation, but you talk using a wireless handset, which is completely safe.
Let's not encourage dangerous behavior here. Walking around in a parking lot in a local lightning storm is a bad idea. I think there are different risk levels between distant storms, where the bolt and boom are separated by several seconds, and local storms, where you can directly see the objects in front of you that are getting struck by lightning. You should not be walking around anywhere outside in local lightning storms. Saying that ignoring the risks of lightning storms is okay because the average deaths due to lightning is low is like saying drinking bleach is okay because the average deaths due to bleach poisoning is low. They are low because most people are not foolish.
Not true, at least not in the parts of Europe I know.
Some lines are under the ground, some are not.
GOSH thats such a dangerous statement!!
If you had worked in the telecomms industry for as long as I had would would realise how bad saying something like that is.
When I look at the many 100's of destroyed phones due to lightning strikes.
There are still many 1000's of corded phones installed in businesses and homes. and I have seen and had to replace so many that have been blown off the wall/bench as a result of lightning. Fuses and gaseous arrestors only protect from low level excess voltages and currents. Many times those protective devices have been totally toasted by relatively local strikes.
Yup cordless phones and mobile phone are a great safety alternative.
Underground cables .... well yes they are mostly out of harms way when totally underground from the phone exchange to the subscribers premises. But often, particularly in rural areas, there can be long runs of aerial (above ground) line from the u/g cable termination to the subscriber. Lightning striking those aerial lines just feeds straight back into the cable and turns it into a molten trail of copper in the ground.
Nice post, davenm. It's always good to get some practical info from folks on the ground! I worked for Bell for a bit in Denver, and that's the first time I ever saw a destructive "thunderstorm" march across a field. Holy smokes!
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