Heat Exchange/Air Warming Masks

[Craig Shelley]

Hal Weiss in the Secrets of Warmth states that more than 50% of your body’s entire heat production is consumed by breathing when the temperature is 0 deg F.

There is an interesting product online called the AirGuard Health Mask (use google and you will find it if interested). The cost is $9.65.

PSolar has heat exchange masks that are much more expensive.

I don’t know the weight of the AirGuard Mask, but in the older Secrets of Warmth book (1988) it talks about a 3M Air Warming Mask that weighs 1/2 oz.

I think a very lightweight mask of this type could keep one warmer at night and perhaps be used under a balaclava when temperatures get very cold or in an emergency situation.

Anyone using these products?

Craig Shelley

PS: Here’s a review of the Psolar mask. It states it weighs 1.9oz.

http://www.backpackgeartest.org/reviews/Clothing/Accessories/Psolar.EX%20Mask/Andy%20Mytys/Long%20Term%20Report/

[J R]

wear a $.50 dust mask….

[John Chan]

I use the Psolar mask and from what I can see its just corn starch which has been fixed onto a solid medium. I’ve used it to extend my sleeping bag comfort range when I’m camping below 32 F and I’ve taken the combination down to 20 F (with several clothing layers, bivy bag, summer wt foam)… so I would guess that it extends the range of the system by some 10 F.
The downside is you have to “reclaim” that exhaled moisture so breathing is done through the mouth (won’t work, in fact it’ll freeze up if you inhale through your nostrils).

[Craig Shelley]

Joe, have you used a dust mask for this purpose? Do you have any idea how well it worked?

Craig Shelley

[Craig Shelley]

John, are you saying that you breath through your mouth all night long?

Craig Shelley

[J R]

“Joe, have you used a dust mask for this purpose? Do you have any idea how well it worked?”

Ive used lots of things to keep my face warm… A dust mask worked as well as the USGI extreme cold face mask (compair http://www.goldnuggetsurplus.com/online-store/scstore/graphics/HH019%20White%20ECW%20Facemask.JPG vs http://store1.yimg.com/I/maskstore_1875_25965719 ) which worked just as well as a psolar mask I tried.

and they all worked just as well as a balaclava…
which worked just as well as a scarf…
which worked just as well as a shemagh…

For that matter, some Indian tribes in Canada and Alaska used bundles of cedar bark tied over their mouths to help warm the air before it entered the lungs.

All your doing is trapping warm moist air near your mouth so that upon inhaling the cold dry outside air is prewarmed/moistined before hitting the mucus membranes. Masks with more standoff around the mouth keep moisture buildup away from the skin, but they all function in the same general manner.

My big problem with breath warmers is no matter the material, it always deflects warm air into my eyes and causes my glasses to fog.

[John Chan]

That’s the only way… you want to breath in warm air and that happens when there’s a phase change on the starch surface.

There may be other companies that have heat exchangers that cover both breathing orifices.

[paul johnson]

Joe,

Try Rain-X Anti-Fog. Works better than saliva to prevent fogging – wish I had it years ago when I would dive. Works great on bathroom mirrors during long, hot showers even if exhaust fan is not on. I also use it before hiking on my glasses. Sometimes I need to reapply it. I just fill up either BMW mini or BMW micro dropper with it, depending upon whether it’s a day hike or a longer trek.

I guess I’m a bit unclear on the breathing through your mouth. One function of the nose and nasal passages is to pre-warm the air before it travels further along the respiratory tract. So, why are people breathing through their mouth? Granted if it’s cold enough an external “pre-“pre-warmer for the nose might be inorder. Can you please shed some light on this matter?

[John Chan]

Paul,

The heat exchanger on the psolar mask only covers the mouth area which is why you have to breath through the mouth. As I understand it, the principle of warming the incoming air on the exchanger happens through a phase change where the moisture of the outgoing air is captured on the exchanger, and incoming cold air liberates the moisture from the exchanger along with the heat associated with the phase change (from bound H20 to H20 gas). If you only breath out through your mouth and breath in through the nose you will succeed in saturating the exchanger with moisture which will eventually ice up under ambient temperature.
Ideally, the exchanger should cover both breathing orifices but that isn’t the case with the psolar so the user must live with its design limitations.

Hope that explains things,

[paul johnson]

John,

Many thanks for the reply. I pretty much understood what you explained. Since I haven’t used/experienced the system you’re speaking of, I’m just wondering why this artificial means of warming air is considered superior to our own inherent warming system (viz., our nose and nasal passages)?

As far as sleeping goes, besides a nice “tunnel” formed by a cinched sleeping bag hood, a scarf, folded bandana, balaclava, etc. can be loosely placed over the face/nose to assist in warming. No worries about fogging up glasses while one is sleeping.

When awake, the Rain-X Anti-fog plus balaclava and/or scarf, IME, have worked well to provide both relatively warm air for inhalation and clear/unfogged glass lenses.

I never breathe (inhale or exhale) through my mouth, either while asleep or even during sustained high heart rates while ascending hills, so I guess such a system that relies on mouth breathing is not for me. Perhaps, it works well for mouth breathers though. If one is not a mouth breather, I’m also wondering how one continuously alters their manner of breathing to use their mouth instead of their nose, particularly while sleeping? Am I missing the whole point of this system?

[John Chan]

Paul,

The major difference between breathing through the nose (inhale to heat in sinus cavity) and breathing through the heat exchanger is the fact that you are re-claiming moisture through the heat exchanger while you can only exhale moisture using your “non-cybernetically enhanced” orifices. The manufacturer claims that you can re-claim 80% of your exhaled moisture through their exchanger although I’m skeptical of this number.
One thing I did notice last year though, is less condensation on the inside of a 2 man tent after a -20 C night using the exchanger. And for the price of breathing through the mouth all night you don’t have to saturate the breathing tunnel of a winter bag and breathing warmed/moistened air is definitely less laborous than breathing in cold/dry air… even through the nose. Your sleeping bag stays drier too since you sweat less inside to stay warm.

[paul johnson]

John, thanks. That explanation hit the nail on the head – exactly the points I needed clarification on. Just one more question: what do you use, something like a swimmer’s nose clip (?), to close-off the nose so that all breathing is done through the mouth?

[John Chan]

Paul,

As to your other inquiry about training to breath in through the mouth, I am also a natural nose breather but I found it easy to train for mouth breathing. A couple of -30 C days/nights and having much warmer extremities through heat conservation (using the exchanger) really convinced my body to do it the other way fast!

I think under those extreme conditions your physiology will adapt to using the device without too much fuss.

[paul johnson]

John, Thanks again. Sounds like it’s worth a try.

[J R]

Paul, thanks for the tip on RainX. I had been advised while in the Army not to use RainX, and being a good little grunt, I just nodded and went on. Might give it a shot on some older glasses to see how that works out.

[paul johnson]

Joe, Just to make sure I’m clear on two points (one mine & one yours):

Mine) I’m speaking of Rain-X Anti-Fog. My current two plastic bottles are BLACK (as was the very first years earlier); not YELLOW like the Rain-X “invisible” windshield wiper bottles. Since I bought my latest two bottles over a year ago, and package colors may change, the product is clearly labeled with the “Anti-Fog” designation.

Yours) Why did the US Army say don’t use it? Damage to the lenses of the glasses??? I’ve used it for years now (since maybe ’97 or so, IIRC) with no damage to my glasses’ lenses.

In a pinch, I’ve used my own saliva – just like all SCUBA divers are taught to do to prevent fogging/condensation on the face mask glass. I still do this sometimes, but the Rain-X Anti-Fog works better.

Oh…BTW…two other things that seem to affect fogging of glass lenses in very humid or rainy conditions:

1) don’t stop; keep moving even slowly, and lenses don’t fog up as much, and…

2) use a wide brimmed rain hat instead of a hood and glasses don’t fog up as much. A bit more on the hood: the more the hood projects forward (sure it keeps driven rain off of the face) the more the glasses fog up.

Also, put the RainX Anti-Fog on both sides of your lenses, especially the inside/side-towards-your-face, and DON’T TOUCH your lenses afterwards or you will need to reapply it if you touch the lenses too much.

[J R]

“Why did the US Army say don’t use it? “

Not sure, LOL, never asked. It wasnt an army wide policy or anything, just that the First Sergeant said not to do it, because he tried it once and it messed up his glasses. Then another sergeant spoke up and said the same thing. Said it took him weeks to get his glasses back to normal because once he sprayed the RainX on, nothing would get it off (everything just kept beading up and running off).

[paul johnson]

Joe, Since they were experiencing “sheeting action”, it sounds like they were using the regular RainX instead of the RainX Anti-Fog. The “Anti-Fog” product is formulated differently. It basically eliminates the fogging of the lenses in very humid or rainy conditions. There are never any drops to even bead up on the lenses. I’ve used it since ’97 or ’98 on my glasses. One family member in my household (not me) likes to, on occasion, take 45min showers with almost no cold water. The bathroom is like a steam bath. We live in an old house and 9 mos of the year put an exhaust fan in the window when showering. During cold months, we don’t. After these marathon showers, condensation is on everything (even ready to drip from the ceiling). However, the bathroom mirror is totally clear if it has recently been treated with RainX Anti-Fog. There aren’t even any water drops beading up on it, much less running off. Condensation just didn’t occur even though the mirror is at the same temp as most everything else in the bathroom. If that mirror is not treated, then within two minutes the mirror is totally fogged up.

[Author]

Posts