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mask volume.¿air reserve?

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.


Well-Known Member
Mar 2, 2001


Bill made a comment that he couldn't use 'liquid' goggles because he needs corrective lenses. Actually, fluid goggles work for all eye types, independent of prescription, because the cornea has no power underwater. Thus, even astigmatism disappears. Karoline Dal Toe has bad astigmatism and when she put fluid goggles on, she said she could see better than through any glasses. Of course, the fact that the goggles are not in full production poses serious supply problems at the moment (the waiting list is huge).

Eric Fattah
BC, Canada


Baron of Breathold
Oct 17, 2001

If I'd thought about it, it's the same as scratches on the outside of the plexiglass housing. They disappear in the water. Same refractive index or something.

I did some experiments last week and found it so comfortable to dive with the nose clip that I wanted to give the liquid goggles another try.

Thanks for changing my thinking and I'll let you know how it works out with a little more determination on my part.

Best wishes

Jay Styron

New Member
Aug 31, 2001
Air reserve?

Hi All,
I think this technique is probably better suited for performance freedivers than the general freediver/spearfisherman. The few times I've tried this there has been just enough water, or for lack of a better term "snot" running around in my mask to make this technique difficult to say the least. If practiced enough I guess its a good technique. Just wondering, in a low volume mask are you really getting enough air to make a psysiologic difference or is it just the act of slight inhalation that is giving everybody the percieved benefit? Take care.


Baron of Breathold
Oct 17, 2001
Aloha Jay

I made a few presumptions and a bunch of calculations, I think the answer is both. A great subject. I was taught this technique about 30 years ago and it has become so automatic that I wasn't even aware of doing it.

The math seems to indicate that a 10 second safety factor is available, most of it in the last ten meters. In my case, I must modify masks to seal at the top so, when air excapes it leaves from the bottom and sends any water out first, if I'm pointed at the surface.

Of course, human nature is what it is. If you do this on all dives, you tend to just add the time on at the bottom and eliminate any safety and if you don't always do it you won't remember when it counts. It's the same with taking off your weight belt and holding it in your hand when things become dicey.

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