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Mobile Phones and Lightning a Lethal Mix
An anonymous reader writes "In a letter to the British Medical Journal, doctors wrote that people should not use mobile phones outdoors during thunderstorms because of the risk of being struck by lightning. Usually 'when someone is struck by lightning, the high resistance of the skin conducts the flash over the body in what is known as a flashover, but if a metal object, such as a phone, is in contact with the skin it disrupts the flashover and increases the odds of internal injuries and death.'"
You can then say "at least I was not using my mobile phone" ... duh!
I am no expert, but I would say:
1 - the risk of being hit is quite small if you behave with common sense (for one, stay inside!)
2 - if you are hit, the consequences are quite severe anyway (die or very bad injury) so wether you carry a mobile or not should be a minor difference in the whole picture...
It would be one thing if they said it is more LIKELY to be hit if you used the mobile, but that I cannot deduct from the statement, or?
The plastic cover doesn't have any significant insulating properties. This is /. and I can't draw a diagram, but the insulation probably can't withstand more than about 10kV. For an analogy in relative terms, would you feel safe if the mains wiring in your house was insulated with nothing but a fine layer of dust?
Pining for the fjords
Guess what, neither does air, and that doesn't stop lightning!
Your cellphone does have many internal parts that are metal (including conductive surfaces right next to your mouth and ear). If lightning can find a less resistive path to ground it will take it. Metal objects mean that lightning has to ionize a few cm less air (and if the storm is lucky, the human body will reduce the rest of the distance to ground).
Suddenly, the hairy finger of a familiar monkey tapped me on the shoulder. It was time.--G. T.
Right. But if you get hit by lightning, you're pretty much fscked already.
Your cellphone does have many internal parts that are metal (including conductive surfaces right next to your mouth and ear). If lightning can find a less resistive path to ground it will take it.
If it has the choice between going through air/plastic and tissue, tissue will be the least resistive path. Even a mm of air has more resistance than the human body from head to toe.
I saw a Mythbusters show where they disproved the piercing thing.. they got some model heads (made of some kind of weird Jelly) one of which had its tongue pierced and they then caused a lightning strike to see which dummy got hit - they filmed it with high speed cameras which was cool - however - it was totally random which head got struck by the lightning- until they filled one of the heads with a load of nuts and bolts, at which point that got struck the most.
I think this point was dispproved also - but to be fair they were using a Jelly head and not a real one! - the tongue stud sustained no damage at all when the lightning struck it (it actually hit the top of the had most of the time I belive)
For those that simply like to play the odds. Here are the odds of dying in one's lifetime so one in :
(For the impatient, lightning is 92 on the list, other gems are accidents, self-harm, assault, accidental poisoning, falling down, drugs, walking down the street, cars, bikes and things, fire, #28 is getting medical care, etc. Fun list!)
64 Nontransport Unintentional (Accidental) Injuries [[ more characters to get past the lame lameness filter ]]
118 Intentional self-harm [[ more characters to get past the lame lameness filter ]]
211 Assault [[ more characters to get past the lame lameness filter ]]
212 Accidental poisoning by and exposure to noxious substances [[ more characters to get past the lame lameness filter ]]
218 Intentional self-harm by firearm [[ more characters to get past the lame lameness filter ]]
228 Car occupant [[ more characters to get past the lame lameness filter ]]
229 Falls [[ more characters to get past the lame lameness filter ]]
247 Other and unspecified land transport accidents [[ more characters to get past the lame lameness filter ]]
264 Other and unspecified person [[ more characters to get past the lame lameness filter ]]
315 Assault by firearm [[ more characters to get past the lame lameness filter ]]
451 Narcotics and psychodysleptics [hallucinogens] n.e.c. [[ more characters to get past the lame lameness filter ]]
472 Other and unspecified fall [[ more characters to get past the lame lameness filter ]]
490 Accidental exposure to other and unspecified factors and sequelae [[ more characters to get past the lame lameness filter ]]
541 Other and unspecified drugs, medicaments, and biologicals [[ more characters to get past the lame lameness filter ]]
576 Intentional self-harm by hanging, strangulation, and suffocation [[ more characters to get past the lame lameness filter ]]
612 Pedestrian [[ more characters to get past the lame lameness filter ]]
675 Other accidental threats to breathing [[ more characters to get past the lame lameness filter ]]
679 Intentional self-poisoning [[ more characters to get past the lame lameness filter ]]
771 Event of undetermined intent [[ more characters to get past the lame lameness filter ]]
869 Occupant of pick-up truck or van [[ more characters to get past the lame lameness filter ]]
997 Other and unspecified means and sequelae [[ more characters to get past the lame lameness filter ]]
1032 Other fall on same level [[ more characters to get past the lame lameness filter ]]
1081 Accidental drowning and submersion [[ more characters to get past the lame lameness filter ]]
1117 Poisoning [[ more characters to get past the lame lameness filter ]]
1159 Motorcycle rider [[ more characters to get past the lame lameness filter ]]
1179 Exposure to smoke, fire and flames [[ more characters to get past the lame lameness filter ]]
1267 Inhalation and ingestion of other objects causing obstruction of respiratory tract [[ more characters to get past the lame lameness filter ]]
1310 Complications of medical and surgical care and sequelae [[ more characters to get past the lame lameness filter ]]
1366 Exposure to inanimate mechanical forces [[ more characters to get past the lame lameness filter ]]
1433 Other and unspecified means and sequelae [[ more characters to get past the lame lameness filter ]]
1471 Uncontrolled fire in building or structure [[ more characters to get past the lame lameness filter ]]
1796 Assault by sharp object [[ more characters to get past the lame lameness filter ]]
2331 Fall on and from stairs and steps [[ more characters to get past the lame lameness filter ]]
2811 Drowning and submersion while in or falling into natural water [[ more characters to get past the lame lameness filter ]]
3056 Exposure to forces of nature [[ more characters to get past the lame lameness filter ]]
3285 Other and unspecified drowning and submersion [[ more characters to get past the lame lameness filter ]]
3638 Antiepileptic, sedative-hy
They have done several "lighining related" tests.. going by some of the tests they have done.. a cell phone is NOT going to increase your chances of being struck my lightning.
In fact.. to get the lighning to always strike a head with a piercing on it they had to have about 5lbs worth of metal on or in the head target, and rarely did it actually HIT the metal in the head (untill they added the 5lbs or so.. the big metal door knob in the head finally did it).
Statisticly.. the metal you wear or a phone is not going to make you more of a lightning magnet than no metal / cell phone.
It is still wise though to bend over and grab your toes if you are out in the middle of a lightning storm, they say the ass is the safest place to get hit....
Most simple pagers are one-way, they are NOT in communication with the paging system, but are simple receivers on a specfic frequency. They listen to the signal and receive ALL of the pages, but only when a page "addressed" to the pager is received do they activate and display it.
Nuts and Volts had an article a few years back on how to build a pager-receiver which would watch the whole data stream. It's generally not encrypted (i.e. don't use pagers to send sensitive data, like patient IDs or Credit Card numbers) and easily intercepted.
Now, the newer generation of devices which ARE two-way (crackberries, SMS, etc) do actively transmit. They have to update the network with their location so the calls can get routed properly.
at a billion volts everything is a conductor. You could hold a glass or rubber rod high in a thunderstorm and get much the same thing you would with a metal pole. and let's not hear anymore nonsense about electricity "taking the path of least resistance". it does not, MOST of a given current flow will do that, but parallel paths with more resistance will also be taken, but by less current. Even if you short your car battery holding a bus bar with two hands, there's a small amount of current going through your body too.