Downed power lines

[GoldDigger]

There was a very recent electrocution in Portland, Oregon, during an ice storm. (The linked story may be behind a paywall for some of you.)
A power line fell on a parked car and three occupants were killed when they go out of the car while the line was still energized and tried to walk away.
Please stay safe inside your Faraday Cage until rescued.
A baby who was also removed from the car survived, possibly because of its small size relative to the voltage gradient.

 

[synchro]

A power line fell on a parked car and three occupants were killed when they go out of the car while the line was still energized and tried to walk away.
Please stay safe inside your Faraday Cage until rescued.

That reminds me of a picture from an article in an old Popular Mechanics where that principle was demonstrated:



I wouldn't want to do that in a car with a sunroof, however.

Link to the article:
https://books.google.com/books?id=1...PA82#v=onepage&q=automobile lightning&f=false

 

[Elect117]

I would also like to add, that most utlities have a hard time testing open circuits due to the nature of the fault.

Some utilities still use "burn through" methods on high resistance faults.

And, re-tests to see if the line cleared.

 

[mtnelect]

There was a very recent electrocution in Portland, Oregon, during an ice storm. (The linked story may be behind a paywall for some of you.)
A power line fell on a parked car and three occupants were killed when they go out of the car while the line was still energized and tried to walk away.
Please stay safe inside your Faraday Cage until rescued.
A baby who was also removed from the car survived, possibly because of its small size relative to the voltage gradient.

On the news last night, same situation. Water & Power linemen recommended that if you have to get out of your car always land on both feet at the same time, not one at a time. This to prevent a difference of potential between the feet ?

 

[Elect117]

Ya, it is step potential. Crushed rock is the best defense to it. I haven't done any ground grid studies myself, but that is pretty much all they come back with.

It wouldn't really help in the ice, snow or rain. Especially on cement and wet dirt. The first issue is pushing the material and the second is slipping and falling (and your body isn't going to land in one spot).

The goal is to reduce the space between your feet. As an example both feet together is the same potential, as soon as you take a step of about 3' or so, your planted foot is still at the old potential. Your moving foot hits the floor and now your have a difference in potential which can shock you.

 

[LarryFine]

If the line is on the car, as in the OP, the deadly voltage is between the car and the ground.

 

[Elect117]

From the photos of the accident, it looks like the wire is on the ground as well.

 

[Hv&Lv]

From the photos of the accident, it looks like the wire is on the ground as well.

It is. Looks like it is #2 bare conductor and there isnt enough fault current to trip an overcurrent device. Fuse, recloser, etc..