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The old SAS Survival Handbook (by John Wiseman) contains the advice that if you feel any “tingle” in a thunderstorm, get on the ground, preferably hitting the g

The old SAS Survival Handbook (by John Wiseman) contains the advice that if you feel any “tingle” in a thunderstorm, get on the ground, preferably hitting the ground with your hands/arms first. I wonder how much it’s based on anything that helps in real life. (Stretching out arms sounds strange, don’t you want to minimize your reach of contact points with the ground, considering how many V/m there will be if lightning strikes close to you?)

qbasic_forever 4y ago
Yeah the ground strike effect for lightning is a serious risk. In wilderness first aid classes I've taken that cover lightning strikes the best advice if in a group is to have people spread out as much as possible. If everyone bunches together then one person being hit will just radiate out to everyone else with nearly as much energy. Better to be spread out so at least someone might survive and deal with the victims. Not a good situation though which is why the best protection from lightning is to avoid it entirely!
- b112 4y ago
  which is why the best protection from lightning is to avoid it entirely We're a little coddled now though, I'd say. Just being on the farm, 20 acres back (a few miles), and a surprise storm... where do you go? Under the tress, surely not! Laying flat may be the only hope. People used to be outside more, I'd say. I wonder what the historical vs modern wrt population strike numbers look like?
dmckeon 4y ago
The US CDC suggests crouching, among many other suggestions: https://www.cdc.gov/nceh/features/lightning-safety/index.html https://www.cdc.gov/nceh/features/lightning-safety/index.htm...
mmastrac 4y ago
Ideally you want to avoid current across the heart -- you're probably not going to have a great time being a conductor, but ensuring the easiest path is through your legs/arms gives you the best chance of making it out alive.
- the_arun 4y ago
  Does having a pacemaker increases the risk for the heart in these situations?
  - mwint 4y ago
    I’d guess the biggest risk increase is from having a heart that needs a pacemaker in the first place. The pacemaker itself probably isn’t designed for lightning strikes, but it probably is designed to survive hits from a defibrillator. I’d put money on a pacemaker/ICD surviving a lightning strike.
mywacaday 4y ago
I got my hands on that book as a approx 10 year old. My friends and I had great fun building the deadfall tripwires around our tree house although with bags if wet leaves rather than tree trunks.
- kzrdude 4y ago
  It is a great book. I loved it in childhood and know many of the chapters
xani_ 4y ago
>The old SAS Survival Handbook (by John Wiseman) contains the advice that if you feel any “tingle” in a thunderstorm, get on the ground, preferably hitting the ground with your hands/arms first. I wonder how much it’s based on anything that helps in real life. Well, hitting the ground with your face first would be unpleasant > (Stretching out arms sounds strange, don’t you want to minimize your reach of contact points with the ground, considering how many V/m there will be if lightning strikes close to you?) I'm guessing it's to basically try to be as flat as possible, covering head would make you be overall higher off the ground Most of the advice I've seen pretty much goes by "just try to be least conductive target around"
- amelius 4y ago
  > Most of the advice I've seen pretty much goes by "just try to be least conductive target around" But also try to be not around a slightly worse conductor, like a tree. A slightly better conductor is also not a good idea (getting 1/2 of the current is still deadly).
  - xani_ 4y ago
    Would tree be bad conductor tho ? It's more conductive than air, much taller than average human, and probably similar in conductivity when wet
    - dredmorbius 4y ago
      Trees where lightning is prevalent are often wet, the water itself often containing dissolved salts (which enhance conductivity). Current tends to flow around and over things, rather than through them. That is, on the surface. Which means that the conductivity of dry wood ("through") matters far less than the conductivity of slightly mineralised water ("over" or "around").

qbasic_forever 4y ago

Yeah the ground strike effect for lightning is a serious risk. In wilderness first aid classes I've taken that cover lightning strikes the best advice if in a group is to have people spread out as much as possible. If everyone bunches together then one person being hit will just radiate out to everyone else with nearly as much energy. Better to be spread out so at least someone might survive and deal with the victims. Not a good situation though which is why the best protection from lightning is to avoid it entirely!

b112 4y ago
which is why the best protection from lightning is to avoid it entirely We're a little coddled now though, I'd say. Just being on the farm, 20 acres back (a few miles), and a surprise storm... where do you go? Under the tress, surely not! Laying flat may be the only hope. People used to be outside more, I'd say. I wonder what the historical vs modern wrt population strike numbers look like?

dmckeon 4y ago

The US CDC suggests crouching, among many other suggestions: https://www.cdc.gov/nceh/features/lightning-safety/index.html https://www.cdc.gov/nceh/features/lightning-safety/index.htm...

mmastrac 4y ago

Ideally you want to avoid current across the heart -- you're probably not going to have a great time being a conductor, but ensuring the easiest path is through your legs/arms gives you the best chance of making it out alive.

the_arun 4y ago
Does having a pacemaker increases the risk for the heart in these situations?
- mwint 4y ago
  I’d guess the biggest risk increase is from having a heart that needs a pacemaker in the first place. The pacemaker itself probably isn’t designed for lightning strikes, but it probably is designed to survive hits from a defibrillator. I’d put money on a pacemaker/ICD surviving a lightning strike.

mywacaday 4y ago

I got my hands on that book as a approx 10 year old. My friends and I had great fun building the deadfall tripwires around our tree house although with bags if wet leaves rather than tree trunks.

kzrdude 4y ago
It is a great book. I loved it in childhood and know many of the chapters

xani_ 4y ago

>The old SAS Survival Handbook (by John Wiseman) contains the advice that if you feel any “tingle” in a thunderstorm, get on the ground, preferably hitting the ground with your hands/arms first. I wonder how much it’s based on anything that helps in real life. Well, hitting the ground with your face first would be unpleasant > (Stretching out arms sounds strange, don’t you want to minimize your reach of contact points with the ground, considering how many V/m there will be if lightning strikes close to you?) I'm guessing it's to basically try to be as flat as possible, covering head would make you be overall higher off the ground Most of the advice I've seen pretty much goes by "just try to be least conductive target around"

amelius 4y ago
> Most of the advice I've seen pretty much goes by "just try to be least conductive target around" But also try to be not around a slightly worse conductor, like a tree. A slightly better conductor is also not a good idea (getting 1/2 of the current is still deadly).
- xani_ 4y ago
  Would tree be bad conductor tho ? It's more conductive than air, much taller than average human, and probably similar in conductivity when wet
  - dredmorbius 4y ago
    Trees where lightning is prevalent are often wet, the water itself often containing dissolved salts (which enhance conductivity). Current tends to flow around and over things, rather than through them. That is, on the surface. Which means that the conductivity of dry wood ("through") matters far less than the conductivity of slightly mineralised water ("over" or "around").