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DEEPEST FREEDIVER EVER

Descent of 541 Feet Planned Oct. 12 in Dominican Republic

Imagine descending on a weighted sled to an underwater depth of 541 feet (165m). Think about doing it without a submersible, diving bell, submarine, or even a scuba tank. Now imagine diving on a single breath of air. Such is the
challenge facing Audrey Mestre, 28, of Miami, Fla., as she attempts to becomethe deepest freediver ever. In fact, deeper than even her husband, Francisco “Pipin” Ferreras, 40, who holds the current “No Limits” record of 531.5 ft.
(162 m).

The International Association of Free Divers (IAFD) in conjunction with Viva Dominicus Beach, located in La Romana, Bayahibe, Dominican Republic, will host this freediving world record attempt on Oct. 12, 2002.

For the competition in the “No Limits” category, Mestre will rocket down a vinyl-coated stainless steel cable on a weighted sled, then will return to the surface beneath an inflated lift bag for a total elapsed time of approximately 2-1/2 to three minutes. Her previous “No Limits” record dive
was 426.5 ft. (130 m), set in May 2001 off the coast of Ft. Lauderdale. She is currently ranked the world’s fifth deepest freediver, male or female.

Audrey Mestre will have to overcome intense pressure. At this depth she will be subjected to 241 pounds of pressure per square inch, 16 times the normal atmospheric pressure - akin to having an NFL linebacker standing on every single square inch of her body.

Mestre’s depth will be confirmed by careful measurement of the guide wire, a diving computer on her wrist, visual confirmation from 10 safety divers, and a computerized depth gauge worn on her back. The dive will be sanctioned and covered by the International Association of Free Divers (). The attempt will be filmed in high definition digital for the upcoming film Oceanwomen. If Audrey succeeds, she will hold the record for the deepest ever freedive by a human, male or female.

Freediving is perhaps the oldest form of undersea exploration. Using little more than fins and sometimes a mask, a diver descends on a single breath of air. To many, the sport of so-called breath-hold diving is the purest form
of underwater accomplishment. Purists use the term “apnea” which means without breathing. “No Limits” is the most extreme form of the sport. To avoid wasting air to adjust the pressure inside the mask, competitive freedivers
do not even wear a facemask. They use only fins, and perhaps a nose plug to aid in the rapid equalization of pressure in their ears.

....I think this is one that most people can't say, "been there, done that".

Hope this was of interest to anyone,

FantaSea Scuba & Travel

Thanks for the update.
Going to that depth and dealing with the pressure is incredible... Although it's not the purest form of freediving, the No Limits Discipline has got to be one heck of a rush. I'm like most freedivers, show me Constant Ballast records and then I'm really impressed! In the No Limits there is no expelling of energy, but there is the tremendous amount of pressure, cold, and darkness to deal with. She will no doubt, not use a mask, maybe wear fins but never use them (some people wonder why Pipen endorses fins). She will fill her sinus cavities and eustachian tubes with water to compensate the pressure, a technique I'm not fired up about learning (and to me is the most impressive thing about the No Limits divers). And HOLY PRESSURE... I CAN'T IMAGINE!!!!

Not trying to take away from the No Limits divers, it's just that it is a completely separate discipline to what I think of as pure freediving. Now, Please don't tell me that the most pure form of freediving would have to be without swimsuit.

Just my opinion folks.. but it is shared by many other freedivers/spearfishermen.

Impressive none the less.

Fred

I can understand the pressure changes in the body's air cavities causing concern. But the pressure on the rest of the body shouldn't matter much. The body is mostly water anyway. Am I missing something?

Jason,
You're right, the bodies air cavities are affected and with the main air cavity being the lungs it can get interesting. They fill with a viscous fluid to keep them from collapsing, this actually starts to happen fairly early.. around -120' or so. Other parts of the body, such as the exremeties, let blood flow from them to essential organs of the body. This alone causes many changes in the vital organs. Of course, the heart slows to maybe less than 20 bpm. I've read as low as 7pbm. There are also many other things to deal with such as nitrogen narcosis & O2 toxicity. It's definitely going to be a very risky ride for Audre. I wish her the best! Hold your breath and GO girl!

Fred

Fred -
Never thought about fact that O2 toxicity should be a big risk.
If I have this right, 541 FSW is equal to approx. 17ATA. O2 partial pressure would then be 17 x 0.21 = 3.57ATA O2 exposure for about 2 minutes.
That's seems way over the max 1.6ATA for 45min in the nitrox tables. Don't know the criticality of the time factor, but that high an O2 pressure just sounds bad.
Man, talking about needing antioxidants in your diet....
Dan

Hi Dan,
If your numbers are correct I would imagine the only variable would be the 2 minutes you're using for time at depth. Just what the equivalent time at depth (as to the nitrox tables) would be on a rocket ride down and up I do not know. I have heard that Audre has passed out before on the return to the surface from what they believe was O2 toxicity and then awoke as she got closer to the surface and the pressure was reduced. I found the following link while looking to verify some of the numbers, although it didn't help me with the numbers some may find it an interesting read.

Fred

Further research is needed on this, but some factors to keep in mind: The 02 ATA p.p. and gas exchanges are an issue. But as far as the O2 toxicity, and partial preasures raising enough for these problems to occur, most likely isn't the MAIN cause of her concern.

The mathematical formula your working off of is for BREATHING that gas at those depths. Since Audry will only be taking the SAME single breath with her from the surface to depth, and back, she is not introducing a higher partial pressure into her body from an outside source. When breathing from a tank from depth, it would require "x" amount of gas to fuill her lungs for her to breathe off of, that would require more compressed gas volume than at the surface. Higher O2 pp causing oxygen burns (toxicity) tend to result in higher incedences of convulsion, not blackouts.

Her blacking out on the way to the surface was most likely caused from CO2 build up and Hypoxia in the central nervous system. As she descends, Audry will have the gas exchange in her lungs sending her breath throughout her body. As the pressure increases, her lungs are minimizing their internal holding volume. Upon ascent, those lungs will be drawing gas exchange back from her body to refill their air spaces and thus depleting oxygen from her bodies tissues (and since no new oxygen source a new breath) is beign introduced). This depletion in the brain and central nervous system is what will most likely be a cause if she has a blackout. Most of the professional no limits freedivers have had this occur, many more than once as it has become an "occupational hazard". The safety divers over the years have become well attuned to this occurance resulting in finely-tuned drills practicing getting the freediver to the surface, revived and breathing normal again. Almost all the freedivers int eh circuit today have this and practice this in a pool through their trainign and the days of competition. They train their bodies to get used to the Hypercania/Hypoxia. The blackout itself shows no real long term damages as long and the time period hasn't been too great. Drowning is more of a critical hazard when the blackout occurs more than O2 depletion. (Though, when I've spoken with Pipen and some of the others...I think the 02 depletion may have long terms effects.)

The lungs themselves are very resourceful. They can come together and the walls may actually touch, but the interanl lining in them keeps them from fusing together thus ability them to reshape upon ascent. Most of the time, these freediver will flood the nasal passages and sinus membranes more for the effect that they no longer have to waste the valuable gas in their lungs to help equalize those airspaces upon descent. Instead, they force equalize on the way down, then pull the nose plug, then the water filling the cavilities acts as a tool, to equalize for the diver. Thus the diver no longer needs to use the valsalva techniques or other forms of forced equalization throught the duration of the dive. (Too scary for me though).

I think she'll do alright, its the ascent and the last 10m which are the hard part. The safety-divers though, they have much more risk, but that's another subject. ;D

Quote "This depletion in the brain and central nervous system is what will most likely be a cause if she has a blackout. Most of the professional no limits freedivers have had this occur, many more than once as it has become an "occupational hazard". The safety divers over the years have become well attuned to this occurance resulting in finely-tuned drills practicing getting the freediver to the surface, revived and breathing normal again"

It was my understanding that this passing out I was referring to was not SWB but rather a O2 toxicity reaction. I understood that she revived... not with the help of others but as she got closer to the surface. In this case it could not have been a SWB, as it is when you "awake" from swb your reaction is to breath.. she was, as I understand it, still quite some distance from the surface when she passed out, and it sounded to me like some distance from the surface when she "awoke" (on her own). But hey, it's something I read... written by someone who had communicated with Audre about it. I wasn't there.

Fred

I am saddened by the following news... sometimes you have that feeling that something is going to happen....

Fred
Taken from the deeperblue bulletin board I frequent..

We regret to hear that tragedy has struck the Audrey Mestre's IAFD World Record Attempt in No Limits.

The facts we know at the moment are as follows:

- Audrey Mestre was brought to the surface by rescue divers, during an attempt to do a no limits dive to 171 meters. She was underwater for over 9 minutes. She was pronounced dead at a hospital in La Romana later that afternoon.

There is a bit more info at

Very sad news Fred. No disrespect intended but IMO it just doesn't seem right to risk your life to set a record, what a tragedy. :'(