How safe is it to use the phone when there’s lightning on either end of the line?
Also a word about using cell phones and cordless phones. Is there any circumstances when using them could be dangerous in the rain?
Pretty darn safe if lightning is only at the other end of the line, and the “other end” is not the person down the block.
People have received serious shocks from lightning near their end during thunderstorms. I have heard anecdotally of fatalities, but could not confirm.
Eh…most likely you are completely safe. I have a hard time thinking of a circumstance where you would be any less safe with a cordless phone or cell phone. They do not have an external power source (typically, yes I know they can if charging), and they are not connected directly to a land line.
Relative to other risks, it’s quite safe. People are injured every year due to lightning strikes, estimates put fatalities on the order of 75-300 per year in the US and more than 1000 worldwide (underreported, no doubt), depending on who you ask. I could not find any cites of lightning fatalities that were telephone-related. There were injuries, of course. Most fatalities were linked with outdoor activities.
Here is a link about the medical effects and causes of lightning injury: http://www.emedicine.com/emerg/topic299.htm
Here is a link about the causes and types of lightning as well as safety:
http://205.67.213.10/Information/Lightning/LIGHTNING.htm