They had this discussion in another newsgroup, and it finally came down to
people being told to only have one item of their body in contact with the
ground at any one time. Your choice.
Road Cycling · Public discussion
Struck by Lightning?
Thread navigation
Jump through the discussion
Go to the original post, the replies on this page, or the latest preserved contribution.
Thread details
What we know about this thread
- Original section
- Road Cycling
- Published
- 29 May 2005
- Last activity
- 12 June 2005
- Original author
- Sheldon Brown
- Posts
- 76
- Discussion status
- Public discussion
- Total views
- 2,529
- Views / 30 days
- 0
- Topics
The navigation and discussion metadata provide context. Posts remain in their original chronological order.
-
-
Quoted message said:
NPR ran a story on this morning-lighning deaths fell dramatically with
the demographic change from usa farm life to usa suburb-city life-from
over a hundred a year to few (golfers-farmers-fishermen)
so the bike riding along passages sided with poles and trees is safe
enough.
the NOAA poeple tell us that 'kneel' is incorrect
CROUCH!
Those are both wrong. You need to get flat on your face, mud or no mud.
A $300 suit will do you no good if you are hit. There is a slight early
warning sign in that you hair will start to sizzle and stand up. If that
happens, dive to the ground and get as flat as possible. Even that may
not work because the lightning has already established an ionic trail to
you. The upside is that if you get hit in the hand and not a vital spot
the lightning will just go straight through to the ground.
Bill (former Midwesterner) Baka -
gds said:
Quoted message said:
the NOAA poeple tell us that 'kneel' is incorrect
CROUCH!Correct! You want to minimize the area of contact with the ground.
Basic in every wilderness first aid course.
As I mentioned a few posts back, that is bad advice. If your feet are
the only contact point then the lightning will go through as much of
your body as it needs to get to the ground. Prone is the way to go, and
it doesn't take a panel of experts to figure out the logic, at least i
hope not.
Bill Baka -
Bill Baka said:
gds said:
Quoted message said:
the NOAA poeple tell us that 'kneel' is incorrect
CROUCH!Correct! You want to minimize the area of contact with the ground.
Basic in every wilderness first aid course.
As I mentioned a few posts back, that is bad advice. If your feet are
the only contact point then the lightning will go through as much of
your body as it needs to get to the ground. Prone is the way to go, and
it doesn't take a panel of experts to figure out the logic, at least i
hope not.You're assuming that the lightning hits you directly and then finds its
way to ground. While that's possible, it's more likely that the
lightning hits somewhere near you and then currents flow in all
directions from that point along the surface of the ground.If your only contact with the ground is with your feet close together
then little of that surface current will enter your body and what does
will travel through your legs. OTOH, if you're prone on the ground then
the surface current may enter an arm and travel down to the opposite leg
or arm and pass by your heart on the way. -
Everyone is talking about the hair sizzle effect. What if you have no
hair? Kinda renders the whole matter moot I think.(definetly not looking forward to my next storm ride without an early
warning system. :p) -
Peter said:
Bill Baka said:
gds said:
[email hidden] wrote:> the NOAA poeple tell us that 'kneel' is incorrect
> CROUCH!Correct! You want to minimize the area of contact with the ground.
Basic in every wilderness first aid course.
As I mentioned a few posts back, that is bad advice. If your feet are
the only contact point then the lightning will go through as much of
your body as it needs to get to the ground. Prone is the way to go,
and it doesn't take a panel of experts to figure out the logic, at
least i hope not.You're assuming that the lightning hits you directly and then finds its
way to ground. While that's possible, it's more likely that the
lightning hits somewhere near you and then currents flow in all
directions from that point along the surface of the ground.If your only contact with the ground is with your feet close together
then little of that surface current will enter your body and what does
will travel through your legs. OTOH, if you're prone on the ground then
the surface current may enter an arm and travel down to the opposite leg
or arm and pass by your heart on the way.
I have heard of that and while I am not one of the panel who suggested
it, Ohm's law says different. If the lightning hits you on the top of
your head, the highest point, then it will travel all the way through
your body before getting to your feet. You might do better to crouch and
ball up then roll over onto your side because the last thing you want is
to get a 30,000 amp, billion volt shot to the head. You might survive
but your brain would be fried. Lastly, you might try lying on your back
and put one foot up and take the shot through one leg. This is for
fields only where you have no trees. There is survival, A. As a mental
vegetable (not good) or B. As a guy who walks funny (better). I will go
down flat on the ground if I am caught out in that kind of situation,
rare in California though. I love to watch a good thunderstorm but only
from a safe building with a lightning rod or two on the roof. My house
in Minnesota got hit just two weeks after I ran some 4 gage wire from a
ground stake (fence post) to all the metal points on the roof. The next
day I could see where the lightning had welded some of the wire to the
metal post. I would not have wanted to get hit by that one.
Bill Baka -
Paladin 3000 said:
Everyone is talking about the hair sizzle effect. What if you have no
hair? Kinda renders the whole matter moot I think.(definetly not looking forward to my next storm ride without an early
warning system. :p)
Simple AM radios, no FM, no MP3 player, tuned to a weak but listenable
station will pick up on the hits. In the midwest I could always tell
that there was bad weather in the area when some of my favorite stations
that were either farther away or just low power locals started getting
those occasional loud crackles. At first I thought it was the radio
(1961 Japanese transistor from my sister) but it predicted a nasty
thunderstorm by about 5 minutes. You could probably just wear a wire
with a diode and capacitor into an earphone and when it started to
crackle you should head home.
Maybe I should invent one and sell it to all the hard core riders.(;<😉)
Bill Baka -
Marty said:
Bill Baka said:
Peter said:
Bill Baka wrote:
> gds wrote:
>
>>
>> [email hidden] wrote:
>>
>>> the NOAA poeple tell us that 'kneel' is incorrect
>>> CROUCH!
>>
>>
>>
>>
>>
>> Correct! You want to minimize the area of contact with the ground.
>> Basic in every wilderness first aid course.
>>
> As I mentioned a few posts back, that is bad advice. If your feet are
> the only contact point then the lightning will go through as much of
> your body as it needs to get to the ground. Prone is the way to go,
> and it doesn't take a panel of experts to figure out the logic, at
> least i hope not.You're assuming that the lightning hits you directly and then finds
its way to ground. While that's possible, it's more likely that the
lightning hits somewhere near you and then currents flow in all
directions from that point along the surface of the ground.If your only contact with the ground is with your feet close together
then little of that surface current will enter your body and what does
will travel through your legs. OTOH, if you're prone on the ground
then the surface current may enter an arm and travel down to the
opposite leg or arm and pass by your heart on the way.
I have heard of that and while I am not one of the panel who suggested
it, Ohm's law says different. If the lightning hits you on the top of
your head, the highest point, then it will travel all the way through
your body before getting to your feet. You might do better to crouch and
ball up then roll over onto your side because the last thing you want is
to get a 30,000 amp, billion volt shot to the head. You might survive
but your brain would be fried. Lastly, you might try lying on your back
and put one foot up and take the shot through one leg. This is for
fields only where you have no trees. There is survival, A. As a mental
vegetable (not good) or B. As a guy who walks funny (better). I will go
down flat on the ground if I am caught out in that kind of situation,
rare in California though. I love to watch a good thunderstorm but only
from a safe building with a lightning rod or two on the roof. My house
in Minnesota got hit just two weeks after I ran some 4 gage wire from a
ground stake (fence post) to all the metal points on the roof. The next
day I could see where the lightning had welded some of the wire to the
metal post. I would not have wanted to get hit by that one.
Bill BakaThe problem with those positions is that the pulse goes through your
heart, which is the real killer (ask any electrician). The ideal stance
would be to stand on one leg and lift the other leg high into the air
above your head. That way your head is safe and your heart is safe too
and you won't get voltage differentials from the ground.Marty
It must be fun to live in an ideal world!
Ben
-
08 Jun 2005 19:46:36 -0700 Bill Baka said:
Those are both wrong. You need to get flat on your face, mud or no mud.
A $300 suit will do you no good if you are hit. There is a slight early
warning sign in that you hair will start to sizzle and stand up. If that
happens, dive to the ground and get as flat as possible. Even that may
not work because the lightning has already established an ionic trail to
you. The upside is that if you get hit in the hand and not a vital spot
the lightning will just go straight through to the ground.I'm sorry, Bill, but you're mistaken. The thought that there might be
some way that you could actually get hit by lighting and still survive
is completely without basis. Most people who die from lightning aren't
even struck directly, they're just close enough to be killed. If you
ever happen to see a tree that was struck you would understand that it
doesn't take a direct hit to kill.Yes, you want to make yourself as "short" as possible, but you also
want to minimize your "footprint" on the ground because the lions
share of deaths occur from nearby strikes which cause surface currents
in the ground. If you are spread out on the ground you're the most
vulnerable to those currents.I understand your reasoning, but it's incomplete. There are other
authorities out there with a lot more experience who have come to a
different conclusion.-
-----------------------------------------------
Jim Adney [email hidden]
Madison, WI 53711 USA
----------------------------------------------- -
Thu, 09 Jun 2005 19:44:29 -0500,
<[email hidden]>, Jim AdneyQuoted message said:
I understand your reasoning, but it's incomplete. There are other
authorities out there with a lot more experience who have come to a
different conclusion.Guinea pigs that've spent more than three semesters in a sixth grade
science classroom have a better understanding of the principles than
some self made geniuses.
--
zk -
Marty said:
The problem with those positions is that the pulse goes through your
heart, which is the real killer (ask any electrician). The ideal stance
would be to stand on one leg and lift the other leg high into the air
above your head. That way your head is safe and your heart is safe too
and you won't get voltage differentials from the ground.Marty
Forget having any kids after that one but it does make sense to not
getit through the heart or head. Some lightning is so overwhelmingly
powerful that no matter where you got struck that part of your body
would be instant charcoal. The survival stories have been light to
medium blasts. I have seen one take down a tree over a foot in diameter
and I know that would kill someone or fry their limbs into uselessness.
Bottom line... avoid getting hit in the first place.
Bill Baka -
Peter said:
Clearly you're still assuming that you'll get hit directly rather than
the more likely situation where the lightning doesn't strike you but
hits close enough that you could still be injured or killed by the
resulting surface currents. The advice from NOAA, the Red Cross, and
similar organizations to crouch rather than lie flat on the ground is
based on studies that showed that it's much more likely that lightning
will hit somewhere near enough to you to cause injury than that you'll
be hit directly. The advice is entirely consistent with Ohm's Law.
I won't argue that point but just how many survivors are around to tell
their story of survival? Flat on your back with you feet pulled in and
your hands crossed on your chest with only your back on he ground gives
a minimal area for ligthing to hit or ground currents to to through.
You could always wear a chain mail suit.
Bill Baka -
Quoted message said:
the lines of reasoning prior are basd=ed onthe idea lightning comes
from the sky. lightning does not generally hit you on the head.
lightning comes up from the ground and strikes the cloud.
Correct. But is you feel of hear the pre-strike sizzle it is time to drop.
Bill Baka -
Jim Adney said:
08 Jun 2005 19:46:36 -0700 Bill Baka said:
Those are both wrong. You need to get flat on your face, mud or no mud.
A $300 suit will do you no good if you are hit. There is a slight early
warning sign in that you hair will start to sizzle and stand up. If that
happens, dive to the ground and get as flat as possible. Even that may
not work because the lightning has already established an ionic trail to
you. The upside is that if you get hit in the hand and not a vital spot
the lightning will just go straight through to the ground.I'm sorry, Bill, but you're mistaken. The thought that there might be
some way that you could actually get hit by lighting and still survive
is completely without basis. Most people who die from lightning aren't
even struck directly, they're just close enough to be killed. If you
ever happen to see a tree that was struck you would understand that it
doesn't take a direct hit to kill.Yes, you want to make yourself as "short" as possible, but you also
want to minimize your "footprint" on the ground because the lions
share of deaths occur from nearby strikes which cause surface currents
in the ground. If you are spread out on the ground you're the most
vulnerable to those currents.I was thinking of laying on your back with your feet pulled in and your
arms crossed on your chest. The ground current could only get your back
and the air strike would have a limited strike zone.Quoted message said:
I understand your reasoning, but it's incomplete. There are other
authorities out there with a lot more experience who have come to a
different conclusion.There are always 'authorities' but have any of them ever been hit? There
are way too many authorities who either don't know what they are talking
about or just try to reason by committee.
Bill BakaQuoted message said:
-
-----------------------------------------------
Jim Adney [email hidden]
Madison, WI 53711 USA
----------------------------------------------- -
Zoot Katz said:
Thu, 09 Jun 2005 19:44:29 -0500,
<[email hidden]>, Jim AdneyQuoted message said:
I understand your reasoning, but it's incomplete. There are other
authorities out there with a lot more experience who have come to a
different conclusion.Guinea pigs that've spent more than three semesters in a sixth grade
science classroom have a better understanding of the principles than
some self made geniuses.
Zoot,
You don't even qualify for a comeback, you are hopeless.
Bill Baka -
yup. one has to be outside and watching the sky for weather.
one very serious (if you are outside)lesson i learned watching florida
thunderstorms (searching for tornado formation)is the lightning path
occuring from (or too) a blue sky area 2-5 miles before the cloud's
apparent path.
you know-"gee here comes the thunderstorm... now hwat?
well, odds are at this juncture the storm is overhead for strike
probabilities!add in the cell phone tower (storm king ten pin sounds) effects where
the lightning path no longer goes more or less directly to ground but
heads off to the tower-
then the observation - "gee here comes..." - no longer "holds"arlene is invigorating(like the NE coast) and now abreast butt we are
a-hole deep in water. -
Bill Baka said:
I was thinking of laying on your back with your feet pulled in
and your arms crossed on your chest. The ground current could
only get your back and the air strike would have a limited
strike zone.Any current flowing trough part of your back is too close to the
heart for my liking.John
-
John Henderson said:
Bill Baka said:
I was thinking of laying on your back with your feet pulled in
and your arms crossed on your chest. The ground current could
only get your back and the air strike would have a limited
strike zone.Any current flowing trough part of your back is too close to the
heart for my liking.John
All right. I will only agree to disagree as to what I would do since I
have been within about 30 feet of a major strike, twice. Once I was
standing on a friends porch and lightning blasted a big tree in his
front yard in two (Chicago area). The other time my wife and I decided
to go out and chase the lightning strikes and see how close we could get
with the windows open (Arkansas). A bolt hit on her side and again blew
apart a big tree maybe 25 to 30 feet directly to the right of the car.
Since I was talking to her about if we would ever see any strikes up
close I saw it dead center. The bolt itself looked to be about 6 inches
in diameter and blasted the tree like dynamite and it was so loud she
jumped clean across the car into my lap. Both of those times I thought
it was about the loudest thing I ever heard, like being under the muzzle
of a 6" cannon or something. I have never even heard illegal fireworks
that loud.
Bill Baka -
Bill Baka said:
I think you missed the boat on this one. Magnetic fields induce
current in metals, not water, as in humans. I will admit 'wrongness'
only if you can provide a reliable source link.Well, think about faradays law for a minute. The changing magnetic
field is going to induce an electric field. If you place a charge in
that field it is going to move, whether it is a electron in a piece of
metal or some ionic species in a cell. I can't think of a good
reference for this, but here are some people using magnets to induce
smaller currents in human brains at a well regarded institution:http://bidmc.harvard.edu/display.asp?node_id=4637
The idea that magnetic fields mediate some of the injury effects of
lightning is pretty new, it was first proposed in 1998 in a letter to
The Lancet:This mechanism was initialy proposed to explain why some lightning
victims had cardiac failure even when there had been no direct path
for current through their heart. Most of the literature on lightning
was written before it occured to people to consider this effect, but
this is the current thought. I believe it has been tested on puppy
dogs and cute little kittens. Just kidding. I think it has been
tested on mice. Anyways, this is what is going in the text books
these days. If your library has a copy of Harrison's (google
"Harrison's"😉 you can check the index for lightning and this is what
you will find. I can't find an online reference. Anyways, I just
have to take these people's word for it, so if they are wrong, I am
wrong. -
10 Jun 2005 17:38:29 -0700 Bill Baka said:
I think you missed the boat on this one. Magnetic fields induce current
in metals, not water, as in humans. I will admit 'wrongness' only if you
can provide a reliable source link.Magnetic fields don't make current, but _changing_ magnetic fields
generate a voltage, V = -n*dPhi/dt. A voltage across a conductor will
produce a current. The human body is a fairly good conductor, although
certainly not as good as a metal, because it's mostly salt water.Refs? Check any first year Physics or E & M text.
Quoted message said:
Quoted message said:
An exception to the surface effect also occurs if you are holding on
to a large conductive object and the object gets struck. This can
cause the charge on the object to flow through you, with a duration on
the order of thousandths of seconds, which is a thousand times longer
than in a direct hit. This sort of current can and will cause deep
burns, cardiac arrest, etc.Quoted message said:
This part is correct because the metal object if large enough can act
like a tuned tank circuit and oscillate, heavily damped, but still an
oscillating circuit.Sure, tuned circuits are a fact of life, but holding one in your hand
won't change the duration of the lightning strike. There might be some
ringing INSIDE the tuned circuit after the strike is over, but once
the strike is over, there's no longer an external circuit, so the only
current that can still be flowing must be within the tuned circuit
itself.And why would you suggest that the tuned circuit created by arbitrary
metal object would be heavily damped? It might be, or it might not; it
would depend on the object. Besides, if it were heavily damped, it's
oscillations would not outlast the strike, so the original claim
fails.The skin depth is a function of the frequency, not the duration. For
any metal object that you could hold in your hand, its resonances
would have to be extremely high frequency, at least as high as the
strike frequencies, so this still doesn't support the OPs claim that
it would make things worse than a plain strike.The only problem with holding a metal object is that it offers the
chance that you have something protruding higher than you otherwise
would, thus increasing your odds of attracting a strike.-
-----------------------------------------------
Jim Adney [email hidden]
Madison, WI 53711 USA
-----------------------------------------------
Active in the last 60 minutes
Active in this thread
0 users · 1 guest ·0 bots ·1 total
No signed-in users are active right now.
No known search crawlers active right now.