"air bell"?

[The111]

I don't know much about freediving from a technical side and I know even less about SCUBA. I taught myself to freedive at Blue Springs in Orange City, FL and have been diving there for years, never going past 60ft. I found some info on the web about a place called Blue Grotto Springs and am thinking of going there. They advertise something called an "air bell" at 30ft depth, sounds to be intended for SCUBA divers, but none of these springs ever mention freedivers anyways - only SCUBA and snorkel as far as they're concerned. What exactly is the air bell? Has anyone been to BG or a place with a similar bell? Is it what is sounds like, some huge inverted dome full of air? Would it be safe to freedive down into it and come up for air? Obviously if you did breathe that air, you'd have to re-ascend slowly and exhale the whole way... even I with my limited technical knowledge know about decompression syndrome or whatever it's called - I'm pretty sure it's *possible* to ascend 30ft with with pressurized air in (leaving) your lungs, if you do it right, but I'm not sure if it's something that's wise to go out and do 20 times in a day for recreation.

 

[efattah]

We have wrecks here which have air pockets in them (left over bubbles from scuba divers). I have breathed in such air pockets while freediving, and then done 'free ascents' slowly exhaling the air. I don't recommend it. There are many dangers, including nitrogen accumulation (leading to DCS), as well as embolism.

Although I figured out how to exhale as I ascended, if you screw up you're dead (a real danger the first few times). Then, even worse, after many such dives I ascended once and 'forgot' I had extra air to exhale. Suddenly my lungs felt like they were going to explode and I suddenly realized I needed to exhale, ....

Eric Fattah
BC, Canada

 

[Roland]

Air pockets underwater mean that it is trapped air. This air may not always be of a healthy breathing quality, ask the cave explorers or even cave divers and you might hear unpleasant stories about that, even people dying. :naughty

You can never be sure trapped air is safe to breathe unless you analyze it at that moment. It is not only the oxygen content that can be wrong but there can be all kinds of unwanted substances in unhealthy concentrations in that air. :duh zzz

Together with the things Eric said about it it can be a nasty thing to breathe during freediving. Many advise against the use of "spare air" bottles during freediving because of potential dangers but at least that air is clean and has a known oxygen content. :waterwork

I must admit that the idea sounds very cool, especially if there are many air pockets in swimming distance of each other you could explore a whole cave with, but I think I will skip the experience and live a healthy life tomorrow. :crutch

:ban

 

[The111]

Thanks for the replies guys. Both of you expressed the main danger being that the air would be dirty (the other danger being the possibility of what I call "pilot error" - making a mistake on your procedure).

Check out this page about Blue Grotto. http://underwaterflorida.homestead.com/grotto.html

They call it a "fresh air bell" and specifically say you can breathe in it. I've also read that is has a "bubbler" which I'm guessing keeps that air supply fresh, because if it wasn't continuously replenished, it wouldn't stay clean for long with people "surfacing" in there and breathing.

I'm still not planning on using this anytime soon, but was wondering if it was doable. But I am thinking about doing it sometime, maybe after receiving SCUBA training and some practiced "exhale ascents" over progressively longer distances. I'd also probably want to go with another experienced free diver who's done it. I'm sure there are freedivers that go to Blue Grotto and do this. That's why I was curious if anyone knew this particular spring.

 

[Roland]

A "fresh air bell" you can breathe in still can mean many things.

To give an example just considering O2:
As a healthy person you can breathe air with oxygen contents between 14% and 100% at sea level quite normally for quite some time. Certainly considering extreme circumstances it could be considered fresh air. At 10 meters depth or at the about 2 bar air pressure in the air bell as low as 8% oxygen might, considering the circumstances, possibly still be perceived as fresh air. When freediving however, you might suddenly notice a big difference between normal air with 21% O2 and higher or lower O2. Low O2 concentrations might give you a big blackout on the way up to the surface and high O2 gives other problems.

This is just talking O2 and there is much more to it. When freediving you do extreme things with the air you breathe and carry in your lungs so you should set much higher standards then others to what you consider as "normal fresh air".

Be careful and take care with such general terms when doing things like freediving.

 

[hypoxiajunkie]

There is no way I would breath in an "air bell": I don't want to explode my lungs. I would only do so in an emergency.

 

[roy_nexus_6]

One of the Problems with "air pockets"

on the wrecks.

If the air in this pockets comes in to contact with the iron hull of the wreck, chances are this "air pocket" has very low or ZERO oxygen content (oxygen gets used up in oxydizing the metal it came in to contact with). Also chances are this air has been in someone's lungs before it got there, which doesn't bod well for the oxygen content eather.

 

[The111]

"long fins"?

I've already admitted I'm a self-trained non-educated freediver. I use $20 "US Diver" fins from Wal-Mart. Do serious freedivers use really long fins or something?

And no worries, I have no intention of doing anything that would risk freedivers' access to springs. I was actually thinking about going to BG and DD this weekend, I'd never been to either of them. That's very disappointing. How do they define freediving? Are you allowed to snorkel on the surface and dive down 20 ft? Not really looking for answers here, just bitching...

 

[tom yerian]

There is no way I would breath in an "air bell": I don't want to explode my lungs. I would only do so in an emergency.

Im a little confused about your statement, " I wouldn"t want to explode my lungs ". How would your lungs explode in a bell by breathing in it ????...Capt Tom:crutch :crutch :crutch

 

[tom yerian]

Re: One of the Problems with "air pockets"

on the wrecks.

If the air in this pockets comes in to contact with the iron hull of the wreck, chances are this "air pocket" has very low or ZERO oxygen content (oxygen gets used up in oxydizing the metal it came in to contact with). Also chances are this air has been in someone's lungs before it got there, which doesn't bod well for the oxygen content eather.

The first part of your paragraph is ok; o2 absorbed by metal and producing Iron Oxide, leaving a nitrogen atmosphere.
Second part is really not in contention, considering the emergency technique of mouth to mouth resusitation...

 

[tom yerian]

"long fins"?

I've already admitted I'm a self-trained non-educated freediver. I use $20 "US Diver" fins from Wal-Mart. Do serious freedivers use really long fins or something?

And no worries, I have no intention of doing anything that would risk freedivers' access to springs. I was actually thinking about going to BG and DD this weekend, I'd never been to either of them. That's very disappointing. How do they define freediving? Are you allowed to snorkel on the surface and dive down 20 ft? Not really looking for answers here, just bitching...

Yes, long fins are the fins of choice for professional feedivers..... Capt. Tom

 

[JPPLAY]

Im a little confused about your statement, " I wouldn"t want to explode my lungs ". How would your lungs explode in a bell by breathing in it ????...Capt Tom:crutch :crutch :crutch

The air expands as you go up so creating so much pressure that your lungs can't handle it. That is why submariners train how to exhale on accent from a downed submarine.

 

[Chad Carney]

Freediving to the air bell at Blue grotto is certainly possible, but not real wise, as it's about 15 feet back under solid rock at the 30 foot depth level. (No direct access to the surface.) See the diagram attached below.http://www.divebluegrotto.com/

I teach scuba classes there when the weather is bad, and I always wear long freediving fins. After making my class dives, I freedive for a while. It's 40 feet deep in the open basin area.

Devils Den is harder (creepy) to freedive in because of the limited light in the air cavern. It's really hard to see where the surface begins when you are ascending. http://www.devilsden.com/

There is really no reason to mess around with compressed air ascents while freediving. Get scuba certified first, and after that if you still feel like you have to try it, (the novelty will likely be gone by then), do it from your tank, in very shallow water.

Attached are two photos looking up at Devil's Den, and one of my "freedive equipped" scuba students from Blue Grotto this year.

Chad

 

[Erik]

Im a little confused about your statement, " I wouldn"t want to explode my lungs ". How would your lungs explode in a bell by breathing in it ????...Capt Tom:crutch :crutch :crutch

:head

Be careful,
Erik Y.

 

[DeepThought]

After making my class dives, I freedive for a while. It's 40 feet deep in the open basin area.

You do aware that freediving after scuba is usually a 'no no', right?

 

[MKDVR]

To answer your question. IMO it's doable. As a scuba diver and newbie freediver I've done all three sites.

Blue Grotto falls back more. It's not as vertical as Blue Springs. The general plan is to follow the permanent line down to the left to 100'. Loop around the breakdown pile and ascend from the other side. You basically swim a horseshoe. On the ascent you can stop and hang out in the air bell before surfacing. With more than 2 divers it gets a little crowded. I haven't dove there in years but know the water level is down quite a bit since then.

Another point is that Blue Springs is up for sale and recently received no bids at auction. I don't what the current status is but you may want to call ahead.

I wouldn't reccommend using the bell except for emergencies. On another note having had an experience with bad air in a wreck I wouldn't reccommend that either. Fortunately I just started coughing right away and didn't just go hypoxic.

As for Devil's Den I definitely wouldn't freedive in there. The vis. can be real crappy sometimes. Especially in the afternoon. It can be difficult to determine the surface from the ceiling sometimes and can you could possibly get lost temporarily. It's a really cool scuba dive with a good light.

 

[Chad Carney]

(I have edited my original statement, because I believe I should not recommend what others can do.) I have, and know many other divers that have, mixed casual shallow scuba and occasional shallow freediving for decades with no problems. Mixing either type of dives to extreme, can and has caused problems.

The water level in Devils Den and Blue Grotto is actually quite high and clear right now. The stairs platform, that is often dry (second photo), was about 5 feet deep.

This is John L, the resident monster cat at Devil's Den! I'm guessing he goes about 40 lbs. You have to stalk him to get a photo, and he wouldn't let me get him in line with my student for a size reference.

Chad

 

[superhornet59]

actually i will be making an air bell possibly. i have a small creek and large basin, and im going to go to the government and see if i can make a dam to flood the basin, making a small lake/ large pond. there is a bridge with three "tunnels" that i will use as a base for my dam, and im hoping that one of the tunnels will go as such:

a wall goes from the top to one meter from the bottom, swimmer reaches bottom and does a U type thing (goes under wall then goes up). normaly it would flood to like 2 or 3 meters until pressure is equal, and either way water bottom will always be equal to how low the wall goes. instead there will be a "pool" to contain the water, and i will open a few scuba air tanks to get the pressure in there. itd be very very large (25 meters long by 3 meters high by 6 meters wide). would rock.

EDIT: and for those of you talking about gasses, there would be plants, special solar lamps would trigger photosynthesis, and negative ion air filters should get rid of other filth.

 

[DeepThought]

DT,

You can scuba and freedive for a long time in 40 feet with no concerns,
trust me on this one.

Don't be offended if I'll avoid doing that in the future.

 

[SThompson]

To be frank, there is nothing worth risking the use of that bell. While it's mildly interesting from a novelty point while on scuba, there really isn't that much to see. And if something goes bad you are in an overhead environment which reduces your already low chances of survival in case of blackout to pretty much nil.

Devil's Den is an interesting freedive just becuase of the catfish. As you can probably tell from the pictures, the cavern has a very small opening in comparison to the cavern itself. Greenery often obscures it even more. On an overcast day it can be VERY difficult to determine where the surface of the water is located.

In addition, every time I went there it was fairly dark. You will need at least 2 lights (primary and backup) and PLEASE check your batteries before you go. Tech diving safety measures apply to freedivers just like scoobies.

The pool itself is relatively shallow around the top, but is fun to play in. The bottom is silt covered rocks. Because inexperienced scuba divers often come here and bounce off the bottom repeatedly, visibility can be good or complete crap just depending on the day. The problem really lies in the overhead environment of a cavern. Anything deeper than 20-30 feet you will be swimming through openings between fallen slabs of rock or in completely submerged caverns. If you bump your head, you are screwed because any buddy breathing on the surface is gonna have a hard time finding you and you aren't going to float to the surface.

I used to live in that area, and while I went a couple of times it's just not as good a dive as the state park in Orange City. It's dark, often times hard to see, and once you have scouted the main cavern and played feeding the catfish there just isnt that much to do. I think I hit a max of 60feet in this cavern but it scared the bejeesus outta me. It was dark, cramped, and I found myself squeezing through small openings to peek at the scoobies. Finally I came to the realization that this was REALLY stupid diving (huge risk to see.....rocks and catfish in an overhead environment).

Orange City is the best freediving in the area that I have found. Fun, clear, safe, relatively deep, and manatees. The only other place that I found any depth and fun was a small sinkhole that was just north of Tampa in the waterways of a housing development. Although you sometimes have to compete with fishermen, in the winter the warm water provides a wonderful haven for the manatees and they are instinctively curious and LOVE to be scratched. While it's pretty murky on top, it clears up about 25 feet down although you will still need a light. Lot's of large fish to peek at and it's a fun dive. A word of warning though, coming face to face with a 1 ton manatee coming at you aggressively out of the murk becuase it wants you to keep scratching can be a......wetsuit cleaning experience. :t

Best of Luck and be Safe!