Diving and lightning

[cudachaser]

I was diving of the beach...Near the end of the dive started noticing strobe lights going off...surfaced and a hellacious summer Florida T'Storm was going on. We got to edge of the reef and just hung underwater till the storm abated.

After that incident I spoke with some lightning experts at work (work for NASA).

Here's the way it was explained to me:

Beach Diving

Worst place to be, on the beach. Stay under water, but you are not big target on the surface. Strike liklihood is kinda low. If a lighting strike is near you the charge will travel around you since the ocean is more saline then your body. Biggest concern would be the concussion of the strike.

On a boat...if you are boarding...bad place to be...the charge is trying to get to the ocean. If you are half in and out of the water, your body can become a potential path.

Fresh Water...new rules

Your body is more conductive than fresh water. When lightning strikes arond fresh water the charge travels along the water surface. If you are on the surface, even some distance from the strike, you can get zapped. Underwater, if touching any solid ground you can get zapped....I would hover not touching any solid wall etc...then the water will act like an insulator.

 

[DiverBuoy]

Lightning and diving

NOAA report on scuba and lighting (not safe)

I also found several reports that commented - if you are caught in the water you are safer staying below the water surface, and the deeper you are the better.

 

[WVMike]

=-) Anyone have any information on what to do if a storm with lightning strikes moves in while under water.

Specifically in regards to lake diving, but I am quessing the ocean is the same.

Are you safer in the water?
Under water?
At the surface?
Or on land?

Any technical or scientific answers would be appreciated.

Thanks

Mike:bolt:

 

[-BlueHole-]

This topic has been discussed also in the past, I did a sarch last week, maybe there you will find useful info

http://www.scubaboard.com/showthread.php?s=&threadid=22911&highlight=lightning

http://www.scubaboard.com/showthread.php?s=&threadid=19301&highlight=lightning

http://www.scubaboard.com/showthread.php?s=&threadid=10479&highlight=lightning

http://www.scubaboard.com/showthread.php?s=&threadid=7157&highlight=lightning

http://www.scubaboard.com/showthread.php?s=&threadid=2150&highlight=lightning

many of those link contains other links,
hope it helps

 

[SCUBedoobedoo]

is it even possible to get struck by lightning 60 feet underwater?

 

[WVMike]

Those links were very helpful,

Thanks

mike

 

[DrSteve]

My local out door pool is paranoid about lightning. One rumble of thunder, one flash of lightening and the pool is closed. Same with the local beach. Yet as a sailor I have sailed through many storms.

So I got to wondering...you are out diving and you surface into a thunder storm...what should you do? Say you get hit by lightening, it's not good period. But what if you are in the water? Also what if there is a strike in your vicinity and you are underwater at the time?

 

[Genesis]

is gradient assuming the water gets hit (if YOU get hit, you're toast!)

In salt water, which is quite conductive, it would have to be very close to get you.

In fresh water though, which is much LESS conductive, you are at far more risk from a "close" strike than in saltwater. That's the bad news.

The good news is that its the gradient between different parts of your body that will get you, not the absolute EMF at any particular point.

So....

If in salt water, don't get hit in the water, and hope the boat doesn't get hit.

If in fresh water, you've got more to worry about, but what can you actually do about it? No point in getting too worked up if you can't fix it, right?

Note that people get killed with some regularity in fresh water marinas when there is a current leak into the water for this reason. In salt water marinas you have to be EXTREMELY close to the source of the leak to get electrocuted due to the greater conductivity of the liquid.

I know it sounds backwards, but that's how it works out.

 

[Knavey]

Learned a lot from that post. Thanks Genisis.

 

[chrispete]

I've surfaced into a couple of thunderstorms and each time we just get out of the water as quickly as possible. I'd think that you would almost be safer underwater than standing in the open covered with metal, but...

Yikes, two posts in the time it took me to write mine, thanks for the info Genesis.