YD Scuba Diving Forums banner

1 - 15 of 15 Posts

·
You want some decorating done ?
Joined
·
146 Posts
Discussion Starter #1
I was watching the lightening from the safety of home and due to my inattentivness at school, I wondered what if the lightening hits the water near a diver. Deep fried or an unpleasant experience?
 

·
apparently diving is fun!
Joined
·
104 Posts
had the experience of being in the water in malta during a lighting storm. Not only in the water, but this was a night dive!
Fantastic light show from under the water - shore cover wern't happy. They told us that the storm had hit several times near by!

Physics of electrical current says when it's hit the water it's earthed out - nothing to worry about as long as you keep your head down..

smudge
www.proscuba.co.uk
 

·
DUE CEO, Booking agent, Coffee maker & Dogsbody...
Joined
·
10,161 Posts
Me and Blan dived the Warilda during a Thunderstorm, i thought there were some very powerful strobes down there at 48m until the penny dropped.

We were fine underwater, however i don't think Ivan and his dog were too chuffed on the boat (Michael Mary).
 

·
Flaccid Member
Joined
·
5,410 Posts
Dave Sydenham said:
It's the big bit of metal strapped to your back which would worry me!! :lightning: :eek:
Naaa lighting would hit your snorkle first and at worst melt your fillings if you were using it at the time :D
 

·
YDs Most Southerly Monkey
Joined
·
6,434 Posts
Mr Grumpy said:
I was watching the lightening from the safety of home and due to my inattentivness at school, I wondered what if the lightening hits the water near a diver. Deep fried or an unpleasant experience?
Personally, I'm guessing that were it to strike near you, most of the electrical discharge would go around you rather than through you, based on the fact that I reckon saltwater would be a way better conductor (due to all those Sodium, magnesium, calcium and chloride ions) than human body fluids which are much more dilute solutions. Add to that your rubber suit (especially drysuit).

Of course, if only 1% goes through rather than around you and the water around you takes 100 amps - ouch, that would probably nbe fatal. So it depends how close you are to the point where the bolt "hits" the water and maybe, whether you are in a wettie, a drysuit or shorts & t-shirt.

Also, you orientation when it hits - if you had your head pointing towards the strike and your feet away from it, maybe the differing field strength between your extremities would be enough to encourage the charge to jolt through you.

I suspect that in that last para, I may be talking bollacks though

Richard M.
 

·
"Three sheds"
Joined
·
12,688 Posts
I'm a freelance scientist, and what you've experienced is technically what's known as a "judder".

Ok. I'm not. But I did do a bit of Physics at school. Basically as soon as the lightening hits the surface of the sea it's gone. If you were in a cave on (or rather under) dry land you'd be fine, and sea water is far more conductive than dry land.

Also you have to ask: where is the lightening "going"? The strike is because of a difference in charge between the sky and the ground / sea. Once the spark has connected the two that's it - lightening finished. In fact I'd be willing to be that if you were at 2m in Wraysbury and the lightening struck the surface above your head you'd be ok.

As aside, I was once in a plane that was struck by lightening. That was scary.

Janos
 

·
Finless: You couldn't invent him...
Joined
·
23,946 Posts
Surely you mean poached and not fried?
 

·
You want some decorating done ?
Joined
·
146 Posts
Discussion Starter #12
Finless said:
Surely you mean poached and not fried?
Boiled even !!

Thanks for the replies ... as Benny hill used to say "learning all the time" ;-)
 

·
Registered
Joined
·
1,277 Posts
arent lightning strikes actually positive charges from the ground heading up to the negatively charge bottom of the cloud? i recall that it was actually the opposite to what it looks like, you kinda just see the residual flash burn if that makes sense.

i think a fair number of people have been struck in water by lightning and lived so you should be alright. although its always recommended you get out of water ASAP!

i do agree that the charge will take the path of least resistance so you may not get a full jolt in water but you will pretty much get a very good shock which could potentially stop your heart and mess with your brain. since the bolt does not have to strike at you but near you to give you a shock.

so on land, if it missess you your pretty safe (aside from side-jumps thingys), in water pretty much guaranteed a shock if your in the vicinity of the strike.
 

·
Registered
Joined
·
2,343 Posts
applepie said:
arent lightning strikes actually positive charges from the ground heading up to the negatively charge bottom of the cloud? i recall that it was actually the opposite to what it looks like, you kinda just see the residual flash burn if that makes sense.
It depends as there are both positively and negatively charged bolts out there. The positive ones are about 100 times stronger than the negative ones!
 

·
Lucky Man
Joined
·
2,163 Posts
Janos said:
As aside, I was once in a plane that was struck by lightening. That was scary.
Ay Carumba, I bet it was! Curious to hear more of this tale Janos if you feel so inclined...

Cheers,
Dave.
 
1 - 15 of 15 Posts
Top