Purge valve = foggy mask?

[fisherdvm]

My nephew bought a brand new fancy mask with a purge valve. We dove together for 4 dives. The first dive it fogged so bad, he could hardly see. The second dive I spat so much spit into it, he got along ok. The third dive it fogged again.

So other folks on the boat suggested scrubbing the mask with some scrubber solution. Then reapplied the antifog solution (not spit). Looking at the photos I took home, he still had fog in his mask after the scrubbing.

My theory is, the purge valved encouraged him to breath through his nose, allowing moist air to condense on the cold glass. This depleted the antifogging chemical, and lead to fogging.

Any ideas or solutions? I feel that the purge valve is the cause here.

 

[spectrum]

Your theory of nose breathing may be correct but the purge valve is probably irrelevant. Any mask will vent nicely around the skirt.

My guess is that you did not finish cleaning the mask and did not test it. Here is how I clean and TEST, before I take it diving.
http://home.gwi.net/~spectrum/scuba_mask.html#cleaning

At times like this some detail in your profile would help gauge the conditions better.

Pete

 

[fisherdvm]

Can't see how updating my profile will help my nephew... But I'll do it for your sake, as you have been most helpful.

 

[spectrum]

Can't see how updating my profile will help my nephew... But I'll do it for your sake, as you have been most helpful.

Well, in this case knowing if you were in Florida or New England water at this time of the year would give some indication of the criticality of doing a top notch job.

Also not everyone's spit works the same as a defogger. Try Baby Shampoo or a good purchased anti-fog.

Pete

 

[fisherdvm]

We dove in Freeport and Nassau. Water temperature was about 72 on the bottom. My nephew tried everything, baby shampoo, and different defoggers he bummed from other folks on the boat. I think the best dive was the second one, when I smeared spit all over the mask. Part of the problem is the kid rinsed the mask too well, but still, I've never seen a mask so foggy despite so much attention to it. I always use spit on mine, and never had too much problem.

I'll email him your link about mask clearing.

 

[CLEAR BLUE]

I have a mask with a purge valve and don't have any problem with fogging at all. I use baby shampoo. I LOVE my mask with the purge valve,

 

[Kim]

I'm trying to understand this..........breath through the nose while diving? How? Even if you're only talking about exhaling....do you really mean exhaling through the mask via a purge valve?
Unless you're wearing a full face mask there's no way you could inhale through it!!!

In any event.....I have a purge valve and there's no reason it should cause fogging more than any other mask AFAIK.

 

[fisherdvm]

I'm trying to understand this..........breath through the nose while diving? How? Even if you're only talking about exhaling....do you really mean exhaling through the mask via a purge valve?
Unless you're wearing a full face mask there's no way you could inhale through it!!!

In any event.....I have a purge valve and there's no reason it should cause fogging more than any other mask AFAIK.

You know what I mean... Wonder where you have been for a while, Kim. Maybe my nephew will have to scrub his mask with a real toothbrush to get rid of the stuff Spectrum noted on his article. They tried to scrub it with a cloth on the boat, maybe it wasn't enough.

 

[Butch103]

Try recleaning the mask with toothpaste (not the gel). When you put the defog or spit in it let it dry then just a quik rinse of water. Should be no issues after. The only time I see masks fog are when they are not clean (or properly cleaned) before they are even used or someone spits in it and right away rinses it. This doesn't work.

 

[Matthew]

Kim, I think he means exhaling through the nose. If you do it often enough it can really cause fogging, though it can happen even with a non-purge mask.