Can't Equalize My Mask!

[dumpsterDiver]

Lots of people say they learn something new or see something for the first time on every dive. Unfortunately for me, I rarely encounter something I haven’t experienced a number of times before. However, I had an interesting thing happen to me a week or two ago. I suddenly found it impossible to equalize my mask by exhaling into it.

A month ago, I would have said something that this was impossible.

I have a mustache and usually have to hold the bottom of my mask against my upper lip and push inward to make sure that exhalation of air from my nose doesn’t leak out the bottom of the mask. I generally push the mask up, so the bottom of the nostrils are blocked by the bottom of the nose pocket rather than actually pinch the nostrils shut. My technique can be used when your hands are full; I can just push the mask against my forearm. Essentially, if I don’t hold the mask and block the nostrils air will leak out the bottom of the mask before sufficient positive pressure has been generated to equalize the Eustachian tubes.

Any way my little problem developed when freediving. Before I freedive, I usually exhale into my mask so there is little or no vacuum and I also over pressurize my ears. I find this head-start on mask and ear equalization saves some air and makes it quicker and easier.

I started a typical dive and apparently got behind in my mask equalization. I was down about 40 feet and the mask was too tight; it was sucked on my face enough to be uncomfortable. I began to exhale out of my nose, and for whatever reason, did not hold the mask tight enough on my face. About ¼ of my breath exhaled out the bottom of the mask (a distinctly undesirable situation for a freediver and a non-event for a scuba diver).

What was so UNUSUAL was that somehow a bunch of air exited the mask, but it did NOT equalize the mask itself. It was still sucked on my face as tight as ever and I was continuing to sink. Definitely got my attention. I could not understand how air leaves the bottom of the mask without being captured within the mask itself. I quickly held the mask a little tighter, exhaled again and captured the air and the mask equalized as it “always” does..

It was very weird, as an instructor, I had always assumed that if bubbles were leaving the bottom of the mask the student’s mask was equalized. Apparently not always.

 

[RJP]

Essentially, if I don’t hold the mask and block the nostrils air will leak out the bottom of the mask before sufficient positive pressure has been generated to equalize the Eustachian tubes.

I could not understand how air leaves the bottom of the mask without being captured within the mask itself. I quickly held the mask a little tighter, exhaled again and captured the air and the mask equalized as it “always” does..

A question/observation for my own clarification:

It seems like your are talking about two different things:

1. "equalizing the pressure/squeeze of your mask"
2. "equalizing your ears by exhaling through your nose"

I mention this distinction because I've seen students confuse the two things, particularly when they "discover" by accident that the act of equalizing their mask will also often equalize their ears. When that happens they can get into a bit of trouble because they then assume that these two different things are/should be one-and-the-same. This is further compounded when Instructors and DMs and fellow divers continually reinforce that people should "equalize" without specifically saying "equalize your ears" and "equalize your mask" if that's what we mean. So, what happens is that when they start to exhale through their nose - even before any air exits their nose - their ears may equalize. When they feel the relief of pressure on their ears, they stop exhaling before they have exhaled enough air to equalize the mask volume.

On to your specific connundrum of "how can I be putting enough air pressure into the mask for air to escape, without actually equalizing the mask?" Their are two contributing factors that are relatively simple, and again particularly problematic for new divers if they don't understand the issues.

If you don't equalize your mask "early and often" it will obviously press against your face. Today's better masks (with low-volume design and very soft skirt materials) can press against your face without hurting terribly, and in such a way as to create multiple, discrete "spaces." Particularly when combined with an individual diver's physicial facial characteristics.

For instance, with moderate squeeze my Atomic frameless mask can press gently against the bridge and sides of my nose such that the nose pocket essentially becomes a completely seperate "air space" from the main volume of the mask where the lens is. If I exhale gently through my nose I can "equalize" that tiny little space, and any excess air will have an easier time leaking under the mask vs overcoming the now increasing pressure in the rest of the mask. And it's easy to see how that becomes a negative cycle. As you continue to descend, the mask squeeze gets greater. You try to equalize more often, but since the pressure on the remaining volume of the mask is increasing it becomes even easier for the air from your nose to leave the mask from underneath than to "break the seal" between the nose pocket and the rest of the mask.

It's also easy to imagine that even slow, low-force exhalation through the nose could potentially "deflect" the mask skirt away from your upper lip just enough to make that the "path of least resistance" for the air that you exhale.You alluded to this earlier when pointing out that your technique involves ensuring that your nostrils are blocked by the mask skirt when trying to equalize your ears.

 

[dumpsterDiver]

Sounds like you are much more aware of the issue than me... It was something new for me.

I think you are right about the mask being compressed and the compartmentalized with localized squeeze occuring. Now that you mention it, I know a guy who would come up looking like Rudolph the Red Nose Reindeer... Seems the tip of his nose would get sqeezed and he swore that he would always equalize the mask and exhibited no squeeze synptoms in the eyes or other seemingly more sensitive tissues. Finally a new mask seemed to splve the problem.

with regard to the question: I guess that I just block the nostrils, blow (clearing ears) and then I think I must release a little pressure and then this allows air to leave the nostrils and THEN equalize the mask. That is what I think, but I have been doing it so long it is a reflex and I'm not too aware of what I am actually doing. Yesterday I did probably 60 freedives and one scuba dive, so I go through the cycle of equalizing ears and mask many times on a typical day.

 

[Scuba-Jay]

It was very weird, as an instructor, I had always assumed that if bubbles were leaving the bottom of the mask the student’s mask was equalized. Apparently not always.

Ditto. Will need to keep this in mind next time I'm conducting a skills assessment!