preventing mask from fogging?

[alex_can_dive]

I've just "discovered" a new tip while swimming in the pool with my mask+snorkel today.
When the water leaks in (which is inevitable because there's not much pressure at the surface), I just let it there to block air from coming out of my nose.
No air, no fog

Is this a safe thing to do while under water?

 

[gqllc007]

Sometimes I let a small amount of water on a dive in my mask while diving and gently "roll" or "swish" it around my mask to eliminate fogging

 

[ColoDale]

I do it and use the water for defog sometimes. But it can get in my eyes if I exhale hard out my nose. It won't hurt you unless you need to see right away (at the big killer death fish coming your way).

 

[Divin'Papaw]

Ideally you need to learn breath control so that you can stop air coming out of your nose when you breath. You should be able to breath out of just your mouth closing off your nose internally. Competitive swimmers learn to do this pretty early. I can’t really explain it as I learned to do it at a young age.

Also if you are breathing some air out your nose that little bit of water won’t stop it.

Is your mask THOROUGHLY cleaned and are you using defog on the lense? If not you need to do both of those.

 

[jonhall]

Like @gqllc007 and @ColoDale I sometimes purposely let water in my mask and use it to defog. Blowing gently through my nose gets rid of the water.

 

[alex_can_dive]

Is your mask THOROUGHLY cleaned and are you using defog on the lense? If not you need to do both of those.

It's a brand new mask that I'm trying to "break-in". Done a few things including toothpaste trick, burning the lense and yes, I do use the defog gell (Jaw Spit? I think that's waht it's called).
I'd say it works "OK" .. the mask still fogs up occasionally and nowhere as good as the rental mask I used to use (even though I made sure to buy the same one!)

Anything else I should try?

 

[CuzzA]

I flame the glass and scrub with Dawn. Put the gel defog on and leave it until your next dive. Then before you dive use a little water to clean off the dry defog. Should be good all day. When you're done diving again use Dawn and repeat the defog procedure. If I forget, I always keep a little travel bottle of baby shampoo which works excellent.

Every year before the dive season I flame the glass again and clean the mask up really good trying to remove oils, et cetera.

I rarely have fogging issues, unless like I said, I forget or get lazy with my procedure.

 

[Centrals]

Prevention is better than cure.
Using sea water for defogging is just a temporary measure because the mask will fog up pretty soon.

Mask has to be "break in" and there are so many recommended/suggested methods but I would never use fire. After the initial treatment please test it at home to see if warm air will condense inside the mask. eg. Walk into an AC room with the mask on.
I use my own spit or baby shampoo(if available for FREE) for pre-dive.

 

[TMHeimer]

I wouldn't count on water in your mask as a means of clearing a foggy mask. Use baby shampoo (smear on inside of mask lens, rub with T.P until clear. I have NEVER had a mask fog doing that.
For airway control, practice breathing with only your mouth and "lock down" your nose (then vice versa). You should be able to breathe from each independently from the other. Do this in water with no mask (the "no mask" drill).

As far as exhaling through your nose while diving, you actually have to do that a little when descending to eliminate a "mask squeeze". But this is something that should happen naturally either right away or after one or two dives. It is something I rarely if ever think about. If you are exhaling enough to let water in, go back to the airway practice I mentioned.
But the shampoo will kill all fog no matter what you do, even on the 2nd dive without adding any, and even if water does creep in the mask.

 

[CycleCat]

If you can not breathe out your nose with water in your mask then you have the skill to not breathe out your nose with a dry mask. It's only the water reminding you not to breathe.