Diving and lightning

[ebbtide]

ok i had to laugh at that 1 wouldent have to wait for cooked lobster ,
last year i was in the same situation and i asked my instructor what he thaught on it and his reply was that electricity dissapeats faster in water than on land and he had mentioned that you never see any fried fish after it hits the water ide say ya scairs the poopoo right out of me beacuse i too had a HP 3400 psi steel tank on my back , what a hole in the water that woulda made lol

 

[dkerr]

Now I understand having the poop scared out of me. But would that then be considered a "Fried Warhammer"?!?!?

 

[Rick L]

Humm one other good thing that happened that day was i forgot my polespear. Its home made 5 feet long and made of 3/8 stainless steel tubing(can you say lightning rod hehe)
Was 2 great dives vis was great lots of fish around too.
Rick L

 

[amadeus00]

Don't forget that if you can swim at 8.8 knots while the lightening strikes, you can travel thru time.

 

[Scubaroo]

On a similar note to the polespear, the safest thing to do if you're caught in a lightning storm while playing golf, is to stand in the middle of the fairway holding a 1 iron in the air above your head. Not even God can hit a 1 iron

 

[Uncle Pug]

No... not Uncle Pug's nickname... but have you ever seen lightning while you were underwater?

Today in the continuing saga of ERP's assimilation we were being pelted by hail as we got our gear on. Dark clouds roiled overhead as we entered the water. Winds were topping 20 kts but fortunately our dive site was protected from the waves.

During our dive it got very dark and then there was a bright flash. ERP tells me he didn't see it (but he did see the lightning after we surfaced.)

We decided that there had been enough assimilation for the day.

 

[Walter]

Several times. It's a sign from God that it's time to end the dive.

 

[The Chairman]

I am far safer there than out on land. Most Florida Thunderstorms don't last that long. I prefer to stay deep until it passes.

 

[Aquamaniac]

I read a report about two cave divers who claimed to have been "hit" by lightning whilst in a cave (hill 400 for those in the know).
Im still trying to get my head around how this could happen, using electrical theory. (path of least resistance).

Ill try to find the text body of the message, perhaps WYDT or JamesK may remember it also.

Dave

 

[FredT]

Especially if you are in fresh water!

Fresh water works as a pretty effective insulator at the voltage and current loads involved in a normal lightning strike. OTOH your body is a great conductor compared to the water around you. One of the basics of lightning protection design is that fresh water is not a ground plane, but the rock underneath it is. A really bad place to be, at least as bad as being on a hill playing golf, is diving over a submerged hill in the middle of a manmade or natural lake. The ground plane is closer to the surface there and you are the "short" path. Being down in deep canyon or hole would probably be ok but that will depend on the conductivity of the rocks around you though. Basic rule is to get out of fresh water while the storm is still at least 5 miles away

Seawater is a much better conductor than you are and forms a relatively effective ground plane. You are effectively a high value resistor suspended in a much better conductor. Current will still flow, but it is tiny compared to what will flow around you. This doesn't mean that you'll be OK as you have a huge conductor strapped to your back, you are VERY sensitive to leakage currents, and speargun shafts make a dead short if held vertically. Remember that even 0.1% of a 200,000 amp current is 200 amps. If I recall the numbers correctly current of only 0.050 amps at the "right" point in your heart beat cycle will shut it down.

Given a choice of waiting out a Fla thunder bumper under about 30' of seawater, or making a run across a wide beach with Odin on the rampage I'll hang out deep. If I can get to a properly grounded (or insulated) boat hull or lightning protected area I'll go there over hanging out. I really do NOT want to be the high thing on the beach!

FT