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self-contained inflating life vest?

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.


New Member
Aug 19, 2002
With all the fear of SWB, why don’t free divers use inflatable life preservers with self- contained air supply? It seems like a simple idea, wear an inflatable life preserver, like the marine suspender ones, with CO2 cartridges or other air cylinders and inflate if you are feeling iffy on your assent.

You could take it a step further and have some kind of automatic devise that when a person loses consciousness, would activate the inflation device. I was thinking of something like grenade switch that you removed a pin when ready to dive and hold the switch in the closed position with your hand while diving. If you blacked out, your hand would relax and open the switch causing the vest to inflate.

Now granted, this could cause a little problem spear fishing, but with some ingenuity something could be designed so that if your hand came off the spear gun handle it would trigger the inflation.

I saw where there were some posts about self-inflating SMB’s and someone mentioned AP Vales SMBCi. This sounds useful, but why not lift the whole diver, gun and all and have it support the diver, face up at the surface, if he blacks out? How many lives could this save if this was available in package that was with un-obstructive comfort, durability, etc., and priced affordably?

I have done a little searching and what appears to be the closet to this is marine inflation life preservers with pressure relief valves. I believe a relief value would be essential to keep it from bursting on assent if filled at depth. Most have two 2 CO2 cartridges. Of course they don’t have any trigger mechanism for automatic deployment if loss of consciousness, but they do have pull cords if your still coherent enough to recognize the danger. One question though, will the 2 CO2 cartridges have enough pressure to fill the vest at depth?

What do you think? It amazes me that with all of the vendors vying for a piece of diving market, this product does not already exist. Something similar was used with a small air cylinder in The Deep Blue movie, but I have never seen anything like from dive industry. You can’t even find a snorkeling vest with a CO2 fill port!
I think you will find this topic of great interest to Ricardo Hernandez - a regular Deeperblue contributor. I have a feeling he may well chime in on this topic.

He has some great ideas on how to approach this topic.

Be prepared... ;)
We already have a device. It doesn't cost one penny more until you use it but, it's almost never used. Why? Let me mis-quote Dave Sipperly from last week,
"The first indication of SWB is blackout".
Maybe a timer that starts automatically when you leave the surface and must be reset manually in two or three minutes.
I'm with Bill. Its called the release on your weight belt.

If you're going to go for it down there to the extent that SWB and the like is even a consideration, pop the buckle and hold it in place on the way up. You blackout, the belt goes byebye, you go up. Now all you have to do is hope you land face up and your buddy has his/her wits about them.


Originally posted by donmoore

Now granted, this could cause a little problem spear fishing,...
Did you say LITTLE ?...
but with some ingenuity something could be designed so that if your hand came off the spear gun handle it would trigger the inflation.

What size fish do you spear , Don ? Ever try to hold onto your gun whilst being pulled by eg. a wahoo ?

What do you think?

Know your limits , listen to your body , dive with a buddy , if you like (I don't ) do the weightbelt thing .
While I can go for a timed inflation device for you diving-for-numbers, types, the idea of somthing going off automatically when I'm fishing doesn't thrill me.

I can imagine being down and pulling a fish out of the hole, or diddling around trying to free the shaft from a rock :eek: and having that omnipresent little loop of line casually drifting around my ankle and all of a sudden the thing inflates. I'm tied to a rock, the float wants to go up and I'm in the middle. :hmm

Not that that's ever happened of course.:mute

Use your knife

Use your knife to cut the line. Actually I think I would rather have it go off either by choice or unconsciousness myself, than a timer.

In regards to sven’s answer about “pop the buckle and hold it in place on the way up”, that is a good inexpensive idea. In south Texas, where I dive, the water is in the middle to upper 80’s this time of year, so I wear a 1 mm wetsuit, mainly just for protection against the coral and sea-urgents on the rig legs and the jelly fish. A 3 mm is just too hot. With my 1 mm, I am neutral buoyant at about 16 feet, so I only wear a 2 lb weight. That doesn’t leave a lot of buoyancy to get to the surface in time to keep from drowning, and like you said, “hope that you land face up”.

I would rather have something with more buoyancy and was designed to float me on my back with my face out. I don’t thing any wet suit can do that, but your idea of popping the buckle is a good start and I’m going to give it a try. In fact, if my 2 lbs weight was capable of pulling the cord of the CO2 life vest manual switch, I could attach the belt to the cord. That way, if lost consciousness the weight would pull the cord and inflate the vest. The type of vests I am looking at have 35 lbs of lift, so keeping 2 lbs of weight is no big deal, that is unless the vest isn’t capable of fully inflating due to depth compression. If I decide to give it a try, I will do a lot experimenting and report the results

As for Abriapnea’s comments. Fish are big in Texas and float lines don’t work good in legs of oil rigs. If I was fighting anything big, without scuba, I would appreciate 35lbs of lift helping me get to the surface. So keeping my hand on the gun handle well enough not to activate the life vest switch, is not a concern.

I always thought the knife was to tell others not to stay down longer than you. Or to have better gear than you. Ah well, shows what I know...

Some good thinking on the subject. I planned to set the timer at longest dive ever plus say 10 seconds. That way, when it goes off, you need it.
Pretty sipmle

If the device has a timer, it already has an electronic device (unless it's a mechanical, but o well), when it is due it can start an alarm, no response will float you.

Better from this, is to make the diving computer control the floating, keeping previously defined boundries like depth, or even a dive profile which is WAY unreasnable, like after spending 2mins at 25meter you go down to 50, espacially if u've been freediving for the last hour in max 25 depth.

And maybe even recognize the descending rate of freefall (will need calibration per diver) and will not expect you to freefall after 2 mins down.

I'm sure anyone of you could think of better examples.

A programmable multipurpose computer could be worn on the wrist and communicate with the vest remotely. One can define a set of parameters for the type of diving you will do.
You then stick to your parameters consciously or set them at a point that defies logic.

If you overstay a defined time or a defined depth where water is deep enough to use this parameter. an audible alarm should go off for say 10 seconds during which you can override the impending boost if its accidental or not required.

However. i'm not sure i like the potential bulk of this vest and its drag.

As for dropping a weight belt, i'm fairly confident that in an emergency i will probably forget to do it especially as i always surface with both hands above my head. I've never yet heard it actually being done ?

Weight Belt


You're right about that. I have a friend who is a deep diver and one of the best divers in the USA. He's removed his weight belt (just as Sven described) many, many times but the one time he blacked out, he didn't do it and said it never even came to his mind. Luckily, we were there to catch him because after doing a beautiful Samba dance on the surface for a few seconds, he went out hard.

Scott Turgeon
Last year, I heard about a french made safety jacket for freedivers. I must look into my old magazines, and when I'll find it, I will post a scanned picture.
I remember it worked with a programmable timer automaticaly set on with the pressure, and after X minutes, it automaticaly inflated a small fenzy-like jacket from a small air bottle.
Thanks! Now I must not search this article anymore!
For what I can remember, it was this one, but in french, of course.
I don't know if in the published version it had been improved, but However, I can remember the creator was looking for financial in order to make it.
Do you know if it's finally been made?

Thanks again,
just my opinion...

one of the reasons i enjoy freediving so much is because it is not connected to loads of funky equipment. mask snorkel and fins only. nice and easy.
safety is of course a big issue but for me it´s my attitude, my training and my knowledge of myself that gets me back. i don´t want a computer or other technical device to take away my decision and responsibility.

to compare it with scuba diving : i see countless scuba divers with expensive gear and computers who mindlessly follow the displayed information and/or also mindlessly not follow it.
just having that gear doesn´t make you safer underwater.

back to freediving : why should a programmable floating device or whatever not encourage freedivers to push it unreasonably, just trusting the device???

for pushing depth and time limits i´d i prefer a buddy for support anytime.

but if aybody has some first hand experience with a thing like that french vest i´d be definitely curious about how it feels/works.

a lot more safe dives to everybody


No buddy available

I have the same feelings of not wanting anymore complication. Which is probably the biggest reason I haven’t proceeded with it yet. I would love to get a buddy diver, and God knows I have tried, but the reality is if I don’t go when I have time and the weather is good, I’m not going much. Everyone says “ you should freedive with a buddy”, but I bet at least ½ of the people freedive hunting in this group end up doing it on their own, most of the time. It’s easy to find someone who says, “yea I would like to go”, but when the time comes, their not available. After awhile, I get tired of asking.

Your comment “my attitude, my training and my knowledge of myself that gets me back” is good, but not fool proof. Most of the people who have shared their SWB experience on this and other groups, thought they were within their limits. Most had weren’t doing anything different than they had done before. With so many deaths and close calls in this sport, the more safety you can build in, the better. That means have the most you can of judgment, training, experience, buddy, and floatation.

Next month, my wife and I are taking our first freediving course.
hi don

i see your point.

i also have to say that i don´t hunt so i don´t really know wether that makes a difference. all i read about hunting on the forum gives me the impression (correct me if i´m wrong) that when hunting one can more easily get carried away.

i also freedive most of the time by myself but definitely limit my dives as far as depth and divetime is concerned.

i was lucky recently to find a divebuddy in egypt 2 months ago (erik young) where for the first time ever i realised the extra adventures one can have by having proper backup.

i´m also not competing so therefore i don´t have the ambition to push things when i´m diving by myself.
i´ve learned a lot about safety and dangers (also from the forum as well as from erik) and i do believe that i´m within very reasonable limits.

there´s always a certain risk left when even a buddy might not be enough in some situations but then again that´s part of the game (for me at least).

if there should be any worthwhile development coming up (safety gear) i´m more than willing to check it out.

i love the sea and beeing underwater more than anything and i definitely want to continue beeing there in the blue many more times before i leave this planet for good.

at the end of the day it is upon me buddy or not, gear or not.
so i just keep on learning and training hoping that my way in the sport is o.k.

hope to hear some comment from you.

enjoy your freedive course!



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