Cave diving during thunderstorms

[jpdiver]

All joking aside, do you usually decide to go ahead and cave dive or not dive when those summer thunderstorms roll in as you are gearing up?
I'd love to hear why or why not.

[sdenney]

If I already have my gear setup, then yes. If not, I wait it out or bag the dive depending on the conditions.

[Angie Reim]

Oh hell no! Never again! I damned near died. I can be fully geared up and if there is a strong peal of thunder within what I consider the 15minute time zone (native Floridians are pretty good at this) I'll wait it out until I know the danger has passed.

[Kelly Jessop]

Oh hell no! Never again! I damned near died. I can be fully geared up and if there is a strong peal of thunder within what I consider the 15minute time zone (native Floridians are pretty good at this) I'll wait it out until I know the danger has passed.

Agreed. My buddies and I got hit around the Nicholson tunnel at Peacock

[Capt Tom McMillan]

Yep

I agree with Kelly. I was with him when we got hit by lightning in Peacock.

It was not fun...

[mgersch]

Agreed. My buddies and I got hit around the Nicholson tunnel at Peacock

WOW. Can you elaborate. I really didn't think it was possible to get hit by lightening inside the cave. If you don't mind me asking...

What happened?
Was there a loud noise?
Did you feel an electric shock?
How do you know it was lightening strike?

I certainly worry about lighening when I am on the surface, but I really thought if I was underwater 600 ft back in a cave that I'm fine. Along those lines, I don't know if it helps on not, but on days when I'm diving at Ginny and I come out of the eye only to see its a major lightening storm, I have been known to stay down under the rock ledge and wait it out for another 10 min. I figure, less chance of getting struck there. Maybe I wrong.

[cavedivenut]

Oh hell no! Never again! I damned near died. I can be fully geared up and if there is a strong peal of thunder within what I consider the 15minute time zone (native Floridians are pretty good at this) I'll wait it out until I know the danger has passed.

I also agree. After my incident at Peacock I wouldn't even consider diving prior to a thunderstorm. (read my post in the "Diver killed by Lightening" topic)

[scubaqueen]

I have been wondering about this, and I am glad to hear everyone's responses, especially those who have been zapped while diving. Not being of the scientific type, but knowing some basic things about electricity, I always felt that being in water during an electrical storm was risky, especially wearing steel tanks. I have heard numerous anecdotes about the risks of indoor activities during electrical storms: bathing, using telephones, or coming into contact with anything that conducts electricity, or attracts lightning. My knowledge is limited, but I understand that electricity must have a means to enter and exit your body.

I was wondering if some of you scientific folks out there could offer some advice with the following:

1. Does being inside the cave offer any protection?
2. If you are in water, how close would you have to be to the actual lightning strike before you might feel it?
3. Would it likely matter if you were in a wetsuit or a drysuit?

Thanks.

[DBBDV]

Having been hit once during a cave dive, I whole-heartedly agree with Kelly and the others who have experienced this. I will not start a cave dive if there is any indication that a thunder/lightning storm is approaching.

DB

[FW]

1. Does being inside the cave offer any protection?
It is the water that conducts lightning, so no, the cave offers no protection.



2. If you are in water, how close would you have to be to the actual lightning strike before you might feel it?
My estimate (being on the land when Angie got hit) anything less than a mile.



3. Would it likely matter if you were in a wetsuit or a drysuit?
Probably not, since your head and hands are in the water.

[DeWayne]

Salt water is a much better conductor, so when lightening strikes the surface it tends to radiate out from the strike along the surface. This means that you are likely safer at depth when out in salt water. Fresh water on the other hand is a lousy conductor so the strike penetrates the water column looking for a suitable ground source. This means that in fresh water you cannot count on descending to depth to protect yourself.

[Angie Reim]

3. Would it likely matter if you were in a wetsuit or a drysuit?
Probably not, since your head and hands are in the water.

Well I don't remember if I was technically diving wet or dry at the time of 'the incident' but I do remember that I was wet by the time it was over. :twisted: :lol:

It seems rather silly and academic to debate it further. :roll:

[skip]

I found this Letter on the internet:

We hypothesize that lightning hitting water spreads out mostly along the surface of the water and the more electrically conductive the water is, e.g. salt water, the more it stays near the surface. How far it spreads out along water and remains a danger is even more uncertain. Lightning striking ground can still be dangerous over 100 feet from where it struck. Some believe lightning will go even further in water, because it's a conductor. But lightning in ground often spreads out in 'ground streamers', quasi-radial tendrils of electricity, which allows it to go farther than if it was dissipating uniforming. Some believe lightning is less likely to form these streamers in water, dissipating more uniformly. So the total area affected may be larger than on land, because water is a better conductor, but the distance it remains dangerous may be less, since it may not form ground (sic) streamers. However, I'm extremely confident that "6 feet to the post" is insanely inadequate for safety. At that distance, you're in danger of a lightning 'side flash' from the post through the air to you, even before it finds the water. General lightning safety guidance uses 6 miles as a reasonable compromise between safety and lifestyle impact.


Metal does not attract lightning. When thunderstorms are nearby, there are three main factors determining what gets struck, the objects: 1) height relative to other objects, 2) isolation, and 3) pointiness. But the path of least resistance (technically, impendence) from the cloud to the ground can be very convoluted, so lightning is more likely to strike tall isolated pointy objects, but there are no guarantees. However, large long metal objects are still an especial lighting hazard because if they are hit coincidentally, they can carry the dangerous electricity a long distance. Think of crowds of sports fans pressed against a long metal fence or railing with thunderstorms nearby -- scary!

In Florida, water related activities (swimming, boating, and fishing) is the #2 activity for lightning casualties. You also mentioned loading the boat with lightning nearby. The lightning casualty stories are replete with events where people were within minutes of getting to a reasonably safe location (large fully enclosed building with wiring and plumbing, or a vehicle with a solid metal roof and sides). If they had started for shelter just a little sooner, or hadn't stopped to load the boat or pack their picnic or whatever, they likely would've avoided the casualty. When you consider the threat to life and the more frequent life-long debilitating injuries lightning causes, it is smart to obey the lightning safety guidelines.

A wealth of good lightning safety information is available at
www.lightningsafety.noaa.gov, https://www.patrick.af.mil/45og/45ws/lightningsafety. The latter website has links to 2 excellent websites on lightning and boating.

Since you are in Florida, I'll contact you directly to offer lightning safety training.

Bottom-line: lightning and water related activities are a bad combination. Please learn more about lightning safety and avoid becoming a statistic.

Enjoy! Lightning Safety: https://www.patrick.af.mil/45og/45ws/LightningSafety

William P. Roeder, 45 WS/SYR
1201 Edward H. White II St., MS 7302
Patrick AFB, FL 32925-3238
william.roeder@patrick.af.mil
Primary Office (CCAFS): Secondary Office (PAFB):
(321) 853-8410 (voice) (321) 494-7023 (voice)
DSN 467-8410 (voice) DSN 854-7023 (voice)
(321) 853-8295 (fax) (321) 853-4315 (fax)
DSN 467-8295 DSN 467-4315 (fax)

Mike Holt's Comment: If you have any comments or feedback, please let me know, Mike@MikeHolt.com


Copyright © 2003 Mike Holt Enterprises,Inc.
1-888-NEC-CODE (1-888-632-2633)

-skip

[Kelly Jessop]

Agreed. My buddies and I got hit around the Nicholson tunnel at Peacock

WOW. Can you elaborate. I really didn't think it was possible to get hit by lightening inside the cave. If you don't mind me asking...

What happened?
Was there a loud noise?
Did you feel an electric shock?
How do you know it was lightening strike?

I certainly worry about lighening when I am on the surface, but I really thought if I was underwater 600 ft back in a cave that I'm fine. Along those lines, I don't know if it helps on not, but on days when I'm diving at Ginny and I come out of the eye only to see its a major lightening storm, I have been known to stay down under the rock ledge and wait it out for another 10 min. I figure, less chance of getting struck there. Maybe I wrong.

The dive we did was Waterhole to P1 by way of the Peanut restriction and Cisteen. When we entered Waterhole it was a sunny day,but what we were unaware of in that long dive was that the weather had changed. When we were making the jump from Cisteen line to Nicholson I thought a rock fell out of the ceiling and hit me in the head,because it felt like a sledge hammer,but I couldn't find any silt from a falling rock which puzzled me. My buddies who were about 75' behind me thought a light head had broken and grounded out around them. We continued our dive and when we got to the P1 cavern it became apparent what was happening with the heavy rain and flashes of lightening. We blew off any safety stop and got out quickly. Capt Tom's wife who was in the car said that lightening struck somewhere in the park. Our theory is that a pine tree may have been struck and grounded out near us. Pine trees have moist bark and a long tap root,excellent lightening rod. I recall losing some feeling in my arm for the day,and my little finger for a week. I have a lot of respect for lightening,and call a dive when the weather has changed for the worse.

[Kelly Jessop]

1. Does being inside the cave offer any protection?



I once escaped a tornado warning in the vicinity by cave diving. Not a moment of genius in retrospect because what if a tree fell across the entrance. I am glad I have survived my Darwinian moments.

[Randy Thornton]

Saturday, I was teaching a Advanced Nitrox/Deco class in an open water hole in Utah called "The Crater". We were down about 50 feet, when I started hearing rumbling sounds and started seeing what I thought were underwater camera strobes. I started feeling slight tingling on my face, and them I finally realized what was going on. It was pretty scarry and I didn't dare bring the class any shallower until the storm passed. The top of the crater is about 100 feet above ground level and is the highest point around the area. I'm sure the crater was struck several times over about 2 or 3 minutes. With all of this talk lately about lightning strikes, it really had me rattled! I wouldn't choose to dive in a lightning storm on purpose, that's for sure!

[Dave Lizdas]

Fresh water is a lousy conductor of electricity, while salt water is a fine conductor. Your body is a bag of salt water. It probably conducts electricity far better than the fresh water that surrounds you. If you are in the dissipation area of a lightning strike, you certainly qualify as part of the path of least resistance.

Scary. I've extended my deco to let a thunderstorm pass before I got out.

[nic160]

"salt water is a fine conductor"
So is Mgersch.............

[Line Squirrel]

1. Does being inside the cave offer any protection?
It is the water that conducts lightning, so no, the cave offers no protection.


Actually i'm pretty sure that water does not conduct electricity it's the stuff "in" the water that does, that's why salt water is a better conductor, heavier specific gravity due to all the minerals, etc. dessolved in the water.

I don't believe that distilled water will conduct electricity which proves the point. We need a physics student to chime in.

[Webmaster]

You're right, distilled water has basically 0 conductivity. It's the dissolved solids, which water in karst areas often has a fair amount of, that increase the conductivity.

There are a number of reports I've read of folks quite a distance back in a (air filled) stream cave experiencing odd feelings while standing in a stream. On exit they discovered there was a major thunderstorm going on while they were underground.

[wingman]

Saturday, I was teaching a Advanced Nitrox/Deco class in an open water hole in Utah called "The Crater". We were down about 50 feet, when I started hearing rumbling sounds and started seeing what I thought were underwater camera strobes. I started feeling slight tingling on my face, and them I finally realized what was going on. It was pretty scarry and I didn't dare bring the class any shallower until the storm passed. The top of the crater is about 100 feet above ground level and is the highest point around the area. I'm sure the crater was struck several times over about 2 or 3 minutes. With all of this talk lately about lightning strikes, it really had me rattled! I wouldn't choose to dive in a lightning storm on purpose, that's for sure!

Is that the crater at homestead? i got a dive in there a couple of years ago and if i remember right the crater is shaped pretty much like a volcano that you enter from a walking tunnel bored into the side...it certainly seemed to be pretty much "indoors" with only a small opening at the top. Bill Huth

[scubaqueen]

Never again will I go cave diving (or any other kind of diving, including the bathtub variety) during an approaching thunderstorm. I have been fortunate in my ignorance, not ever to have been shocked during a dive.

Up in my neck of the woods, we have an electric ray that makes its home at a popular dive site. It's huge, and every once in a while, someone who doesn't know what it is, tries to play with it, and gets zapped. Curiously, the description of the electric ray shock (getting hit with a 2 x 4) was very similar to those of you who described being hit by lightning.

Safe diving all!

[Randy Thornton]

Is that the crater at homestead? i got a dive in there a couple of years ago and if i remember right the crater is shaped pretty much like a volcano that you enter from a walking tunnel bored into the side...it certainly seemed to be pretty much "indoors" with only a small opening at the top. Bill Huth

Yes, it was the Homestead crater. The water was way too warm for 4 dives in one day - about 96 degrees. Felt pretty terrible by the time the day was over. It sure is nice and comfortable in the winter however! What on earth were you doing diving out in Utah?

[wingman]

Yes, it was the Homestead crater. The water was way too warm for 4 dives in one day - about 96 degrees. Felt pretty terrible by the time the day was over. It sure is nice and comfortable in the winter however! What on earth were you doing diving out in Utah?

Had a conference at the resort there, i spend my nondiving time in canyonlands and vicinity...that water was indeed warm...planning a lake powell adventure in september...hope to dive there, you dive any on the lake? Send me a pm...Bill Huth

[scubaqueen]

A wealth of good lightning safety information is available at
www.lightningsafety.noaa.gov

-skip

I checked out this site and it really has a lot of information including survivor stories from those who have suffered lightning strikes. Most of the survivors have residual symptoms, including seizures, headaches, memory loss, fatigue and depression.

I had no idea central Florida was the lightning capital of the US. It is estimated that in a span of 80 years, a person's chance of being struck by lightning is 1/5,000. The scary thing is that it can travel through windows, through telephone and electrical cords, and it can even find you on a sunny day.

Now if you live in central Florida.......hmmmm.......hell, you'd better run inside.

[Wizard]

Attach some 10 guage wire to a copper bar and the other end to you p-valve.
The copper bar drags along the bottom so you are properly grounded.

:lol: