Everyone's heard the lecture on how you shouldn't use the telephone in a storm unless it's an emergency, due to a risk of electrical shock. My understanding is this is true and numerous people have died from lightning striking the telephone wires and electrocuting telephone users. Most reports say lightning enters through one's ear.

How exactly would this work? Most telephone receivers are plastic and plastic does not conduct electricity as well as metal or water. The copper wire from the PSTN connects to the telephone, but the only part of the telephone that you would touch is made out of plastic.

So how exactly can using the telephone be dangerous? Can lightning travel into the plastic part of a receiver and through the air into someone's ear? Is there a way to be safe when using a landline telephone or prevent this from happening?

For example, if you have a speakerphone connected to the line, does that reduce the risk? If you hold the receiver away from your ear, are you safe? If you put metal or water near the telephone, will the lightning strike that instead of your ear?

*If you haven't figured it out, I'm talking about normal landline telephones, not the crazy alternatives that people try using nowadays.

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    \$\begingroup\$ Thought about how lightning travels into the phone line? Any reason to believe it can't use the same means to travel out of it again? \$\endgroup\$
    – PlasmaHH
    Jul 5, 2016 at 13:36
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    \$\begingroup\$ "Breakdown voltage 30 kV/cm at 1 atm." \$\endgroup\$ Jul 5, 2016 at 13:37
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    \$\begingroup\$ "Can lightning travel into the plastic part of a receiver and through the air into someone's ear?" - Yes, it can. A few mm of air and/or plastic are basically no issue for lightning which, to begin with, has enough voltage to travel hundreds of meters through the air from a cloud to the ground... \$\endgroup\$
    – JimmyB
    Jul 5, 2016 at 13:37
  • \$\begingroup\$ I revised my question to make it less vague - are there any steps you can take to make using the telephone safer? For example, using a speakerphone? Holding receiver away from ear? Putting metal/water near the telephone? \$\endgroup\$ Jul 5, 2016 at 13:48
  • \$\begingroup\$ If you hold the receiver away from your ear, you are still holding the receiver... so the electricity flows through your arm instead of your ear. \$\endgroup\$
    – user16324
    Jul 5, 2016 at 13:58

1 Answer 1


Lightning travels thousands of feet from the clouds down to the planet. It is also VERY HIGH voltage and VERY HIGH current. Do you really think jumping a few mm from the wiring in the handset to your body is any particular kind of barrier? Have you ever SEEN the results of a lightning strike?

  • \$\begingroup\$ Lightning will also vaporize the thin telephone wires. I guess what most people mean when they talk about lightning striking electronic equipment is about the secondary effects of a nearby lightning strike. My neighbor's house was directly hit by lightning: the cable ducts in the walls exploded. A hundred yards from there, my whole intercom system was gently fried. \$\endgroup\$ Jul 5, 2016 at 14:50
  • \$\begingroup\$ Lightning doesn't need the thin telephone wires. It vaporizes them because the massive and destructive current has already found a convenient path and the thin telephone wires are just a casualty along the way. You can throw most of the conventional electrical current flow theory out the window when it comes to lightning. It is in a whole class by itself. \$\endgroup\$ Jul 5, 2016 at 14:54
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    \$\begingroup\$ Exactly, my point is that the OP's doubts should be answered according to secondary lightning effects. If your house is directly hit by a lightning, holding the phone will be the least of your problems, if you are less than a yard (ten?) from the current path. But if the lightning hits your neighbor's house, what are the chances the inducted voltages will damage a person holding a phone? \$\endgroup\$ Jul 5, 2016 at 15:00

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