How dangerous is a thunderbolt of lightning while diving?

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Texasguy

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I just don't log dives
Is there a difference between danger in salt water vs fresh?

I don't know much about physics of lightning in water, does the charge go straight down or does make a cylindrical kill zone of some indeterminate diameter?

Would diving at depth make it safer, then how deep?
 
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Chance of getting hit by lightning while diving < chance of getting bitten by a shark < chance of dying from a bee sting << chance of dying driving your car/crossing the street
 
There was a thorough explanation of the physics some time back. If you search, you can probably find it. The bottom line is that unless you are very close to or on the surface you are safe. The electrical charge that hits the water rapidly diffuses widely as it penetrates. So, being a few feet down renders the diver safe. The bigger problem occurs for divers on the surface waiting to get on a boat. Fatalities have occurred from lightning strikes.
 
When lightning strikes the water it is dispersed over a wide area rather then continuing to the bottom in a straight line. How wide and deep the effected area is would depend on the size of the strike. I do not know if there is a safe depth but it would have to be deeper in salt water because salt water conducts electricity far better then fresh water so the effected area would be much larger.
 
Being at depth, probably it would be safer to stay in horizontal position than vertical, judging after how electric charge will dissipate. At least theoretically.
 
Chance of getting hit by lightning while diving < chance of getting bitten by a shark < chance of dying from a bee sting << chance of dying driving your car/crossing the street

I don't agree with yr assessment. :)

I personally know three people who have been hit by lightening while diving and none that have been bitten by sharks.
-I have no fear of being bit by a shark...the reality is it is beyond unlikely: I'd have to be in the wrong place (eyeline of a great white or similar) at the wrong time (when it is so hungry/angry/scared it can't tell i don't look like food).
-I *am* concerned-and rightly so- about getting hit by lightening. As mentioned, I personally know 3 people who have been hit by lightening in the water, one with permanent cardiac repercussions. I also know of several other instances (one or two removed, not Kevin Bacon-related) with various degrees of severity.

Just making a point. I don't dive in thunderstorms even though I am usually "protected" underground in a cave.
 
I do not know if there is a safe depth but it would have to be deeper in salt water because salt water conducts electricity far better then fresh water so the effected area would be much larger.

At least theoretically it should be the other way. Salt water conducts electricity better so the resistance of the water is less and thus at the same distance between two points of the body contacting the water the voltage drop should be less.
Think about birds sitting on electric lines. The wire conducts electricity well so the current goes through it without any harm to the bird
 
....but.....but.....looking up at lightning while diving is cool.....another thing to add to the not safe list. Oh well.
 
At least theoretically it should be the other way. Salt water conducts electricity better so the resistance of the water is less and thus at the same distance between two points of the body contacting the water the voltage drop should be less.
Think about birds sitting on electric lines. The wire conducts electricity well so the current goes through it without any harm to the bird

Because salt water conducts electricity better the effected area will be bigger but the voltage should be less at the outer edges of that area. The only reason a bird can sit on a live wire is because it is not touching anything else at that time. If it touched the pole for example the current would travel through the bird to the pole killing the bird in the process.
 
At least theoretically it should be the other way. Salt water conducts electricity better so the resistance of the water is less and thus at the same distance between two points of the body contacting the water the voltage drop should be less.
Think about birds sitting on electric lines. The wire conducts electricity well so the current goes through it without any harm to the bird


Actually the bird on the wire becomes charged (electrified) to the same voltage as the wire. It isn't harmed because no electricity is flowing through the bird to the ground. If you connected a wire from the bird to the/a ground the bird would be electrocuted. Much the same happens when lighting strikes the water, the water and anything in it become charged but since the charge is equal all around no harm is done.
An example of being at the same potential voltage of a power line.
[video=youtube;LIjC7DjoVe8]http://www.youtube.com/watch?feature=player_detailpage&amp;v=LIjC7DjoVe8[/video]
This could be done without the suit but would feel very uncomfortable, sort of like an intense tingling over the body. Birds don't normally land on ultra high voltage power lines (50,000 volts and above) because of it, they sense it when they get close.
 
https://www.shearwater.com/products/teric/

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