Re:What it’s like to be struck by lightning
by rsync on Thursday May 25, 2017 @03:06PM
(#14419347)
As an aside, as trivia ...
It may interest HN readers to learn (it interested me) that if you are standing near downed power lines (for instance, your car crashed into a pole and it fell, or a storm, whatever) you need to jump away from those downed power lines.
You need to stay in one fixed place and then jump, up in the air, to the next place, and continue to "bunny hop" away from the downed power lines.
The reason is, depending on the amount of moisture in the earth, or cracks in the asphalt, or dirt, or water or whatever, it is possible for there to be a spot where there is more resistance in the ground between your two feet than there is in your two legs and so (if you are walking) the electricity will arc out of the ground, up one leg and then down the other.
Re:What it’s like to be struck by lightning
by Nadya on Thursday May 25, 2017 @03:11PM
(#14419374)
To expand on what you said, since you used crashing into a pole as an example...
If you crashed your car into the pole the safest place for you to be is in the car. Unless your car catches on fire do not leave the car. If you must leave the car do not touch the car and the ground at the same time. Open your door and jump out of the car with your feet together.
Re:What it’s like to be struck by lightning
by devrandomguy on Thursday May 25, 2017 @03:12PM
(#14419376)
This reminds me of an incident report I saw back when I used to work in a warehouse. A forklift driver raised the boom too far, and smashed it into a high power lamp. He immediately let go of the controls, and decided to get away from the forklift, rather than lower the boom, concerned that the metal levers might electrocute him. As soon as he stepped on the ground, he completed the circuit that was preciously blocked by the rubber tires, and paralyzed himself from the waist down.
The report recommended jumping clear, and then using this hopping escape strategy. It did not recommend or countermand moving the vehicle to break a potential circuit; I guess that situation is too complicated for a blanket policy.
Re:What it’s like to be struck by lightning
by zkms on Thursday May 25, 2017 @03:51PM
(#14419670)
> and decided to get away from the forklift
If you're not currently being electrocuted and there's no imminent risk of the situation worsening (or high voltage wires moving) there's little need to put yourself at risk by moving. There's no guarantee that jumping clear/hopping will be safe -- electrical potentials can't be visualised with the naked eye. Even if the power line is touching the ground, the ground isn't perfect and there's still a gradient: https://ehss.energy.gov/sesa/Files/corporatesafety/advisory/... , https://en.wikipedia.org/wiki/Earth_potential_rise
Stay put, call for help, tell people not to get close to the vehicle or the high voltage conductors, and wait until someone de-energises the offending high voltage circuits.
Re:What it’s like to be struck by lightning
by sliken on Friday May 26, 2017 @04:43AM
(#14422762)
Also keep in mind that with a down line always treat the line as live. Apparently if a line is down or shorted the power is cut automatically at a certain point. But afterwards test pulses are sent out to measure the line. Said pulses can easily kill if you happen to be completing the circuit at that time.
Re:What it’s like to be struck by lightning
by flying_dutchman on Thursday May 25, 2017 @03:16PM
(#14419397)
I was struck by lighting in Italy 2.5 years ago. Happy to answer any questions. For background: We were observing and photographing a lightning storm from the upper slopes of Mt Etna in Italy. We were pulled off from the side of the road with several other cars around. Blue sky and no wind - the storm was still far away. There were families with kids and it was a breathtaking scene. I had my 7d mark i on bulb setting to capture the distant lightening, with only my right index finger on the shutter release. I don't remember much more than waking up, paralyzed down the right side of my body. I had an, at the time terrifying but also beautiful fractal burn mark down the right side of my chest. 12h of emergency services followed. The other person struck that day was in the morgue. It turned out to have been the biggest storm in 50 years. I got very lucky and have no side effects to date.
Re:What it’s like to be struck by lightning
by kunstmord on Thursday May 25, 2017 @03:15PM
(#14419396)
Had a "run-in" with lightning a few years ago: while walking to the grocery store with an umbrella, heard what sounded like an explosion (my ears rang for the rest of that day) and was nearly blinded by the bright light, but managed to see a big spark between my thumb and the metal part of the umbrella, and feel a slight jolt of electricity. So, in all probability, the lightning hit a nearby house, and via the lightning rod it all went into the ground and through me (partially)?
No burns, no real damage done to me or the umbrella, but I was really shook up.
It may interest HN readers to learn (it interested me) that if you are standing near downed power lines (for instance, your car crashed into a pole and it fell, or a storm, whatever) you need to jump away from those downed power lines.
You need to stay in one fixed place and then jump, up in the air, to the next place, and continue to "bunny hop" away from the downed power lines.
The reason is, depending on the amount of moisture in the earth, or cracks in the asphalt, or dirt, or water or whatever, it is possible for there to be a spot where there is more resistance in the ground between your two feet than there is in your two legs and so (if you are walking) the electricity will arc out of the ground, up one leg and then down the other.
If you crashed your car into the pole the safest place for you to be is in the car. Unless your car catches on fire do not leave the car. If you must leave the car do not touch the car and the ground at the same time. Open your door and jump out of the car with your feet together.
Then do as rsync said: bunny hop away.
The report recommended jumping clear, and then using this hopping escape strategy. It did not recommend or countermand moving the vehicle to break a potential circuit; I guess that situation is too complicated for a blanket policy.
If you're not currently being electrocuted and there's no imminent risk of the situation worsening (or high voltage wires moving) there's little need to put yourself at risk by moving. There's no guarantee that jumping clear/hopping will be safe -- electrical potentials can't be visualised with the naked eye. Even if the power line is touching the ground, the ground isn't perfect and there's still a gradient: https://ehss.energy.gov/sesa/Files/corporatesafety/advisory/... , https://en.wikipedia.org/wiki/Earth_potential_rise
Stay put, call for help, tell people not to get close to the vehicle or the high voltage conductors, and wait until someone de-energises the offending high voltage circuits.
https://www.osha.gov/OshDoc/data_General_Facts/downed_electr...
No burns, no real damage done to me or the umbrella, but I was really shook up.