How I Started Caring About Heat Exchanger Masks
Back in the 90s I started riding my bike to work after a hiatus of a few years. My coworkers would regularly ask me if I was going to be like Tom, a notoriously all-weather rider. As winter came on, I realized what most people who cycle in the winter do, it isn’t as hard as it looks. It can, however, be cold. With the internet in its infancy, it wasn’t easy to find quality information on how to stay warm in winter, but I knew at the time that my airways were a weak point in that I couldn’t really insulate them from the cold air that passed over them. Then I read about a product called LungPlus and my obsession began.
The Untold Story
The human body is remarkably good at keeping itself heated. The circulatory system will gradually move blood flow away from the surface and away from extremities to keep its vital organs warm. Activity, including shivering, will help by generating heat. But in order to do any sort of activity, one needs to breathe, and in the cold, that means breathing cold air.
The air passages are designed to warm up air as it enters the body so that the blood can pick up oxygen from it. Unfortunately, this is exactly the same as wind chill. On top of that, the airways are damp, which means they are subject to evaporative cooling just the same as if a person was to go outside still damp after a shower. Except that the lungs have approximately 5 times the surface area of skin, and they are always naked.
Well, What the Heck am I Supposed to do About it?
If you stop breathing you will die.
The simplest form of heat retention is the extended hood that Northern peoples have used for millennia. It creates a pocket of warm air around the person’s face, and helps take the edge off breathing in extremely cold air. In turn, this pocket of warm air requires less warming by the airways and lungs and so is pulling less heat from the body.
The next low-tech solution is the scarf, Buff, mask, or bandana across the face. These do capture some heat from the outgoing breath to warm the incoming air, but their primary purpose is to warm the face itself. They are great for preventing frostbite on the face, but they do relatively little to prevent heat loss through breathing.
The next technological step is to use a heat retention or heat exchange device to capture the heat from outgoing air and return it to the incoming air, and that is what this article is about.
Yes, 6 Heat Exchanger Masks.
What follows is a brief description and mini-review of the 6 heat exchanger devices that I personally own. Yes, I could have gotten away without buying more of them, but in my efforts to optimize, I have continued to purchase more.
This device is the only one on this list that does not have a mask with it. It was the first one that I used back in ’99 or ’00. The device is a bit like the mouthpiece of a snorkel with a heat exchanger built in to it. It isn’t fashionable, or really even dignified, but it does work. This is the device I used on the ITI in 2002
- It helps keep glasses unfogged by routing breath away from the eyes.
- It is an effective heat exchanger and helps to keep the body warm
- it routes the captured water away from my chin and reduces beardcicles.
- It is compact for carrying in a pocket or bag
- it is nearly indestructible
- Looks like a science fiction device worn by Venutians to breathe the earth’s poisonous oxygen.
- It routes air through the mouth and I find it sometimes makes my teeth cooler
- droolcicles at the end
Oh yeah, this device lets you breath warmer-than-room temperature air. Oh damn, when I exercise it is like breathing through a straw. This is the best device for waiting for the bus.
- fit is adjustable
- Warm, warm, warm
- Oh, so very warm
- Very restricted breathing, not suitable for any activity.
This device is great, if they still made them, I’d have bought more.
- great heat exchanger
- close fit to the face
- low profile balaclava works well with other hats
- very free breathing and the air path does not ice up
- the exchanger sits close to the lips and can contribute to chapped lips
- the exchanger forms a shelf that can collect snot
- they were bought by another company and were discontinued
This unit is a little more sophisticated than a long hood on a parka, but not much.
- Simple, never clogs
- keeps the mouth and nose clear so skin stays un-chapped.
- no real heat exchange, only a pocket of exhaled breath at the mouth
- some (Tadhg) find it restricts breathing
I bought this one based on a review from a friend with more cold weather experience than me (yes, those people exist).
- Very effective heat exchanger
- good airflow for high-output activity
- keeps wet parts off the face
- the “Darth Vader” look
- great balaclava
- does eventually get somewhat wet
- the “Darth Vader” look
- the great balaclava is a bit tight on my enormous head
This and the Ergodyne are my go-to masks for cooler days. Back to back testing today gives the edge to the AirTrim for warmth.
- doesn’t restrict breathing
- away from the mouth and nose for reduced chapping
- doesn’t put pressure on the nose – less runny nose
- is available with a selection of exchangers with greater flow, or warmer air depending on activity
- Recently, a grade 2 kid said it looked like a pig nose
- it does not cover the upper cheeks – risk of frostbite
- if you neglect to blow the water out of it the water can drip on clothing
Finally a recommendation
On the bike, and this is at least partly a blog about bikes, the Ergodydne (associate link) has the edge because of its coverage of the cheeks. However, if you have or can get a face mask that covers the cheeks and leaves the mouth and nose free, the AirTrim’s superior performance will win out. All this week, I was outside in temperatures as low as -29ºC with the AirTrim on, and I dressed exactly the same as I would have for -12ºC without the AirTrim (yes, it is that good). I now get a commission if you buy it through this Amazon Associate Link to the Airtrim Sport, though I’d still be grateful if the good folks at AirTrim were to send me 3 more for the rest of my family, (hint, hint). I bought my AirTrim from skiwax.ca
Below -25ºC roughly 90% of a body’s heat is lost through respiration. if you could reduce even 15% of that it would be equivalent to doubling your clothes. When you keep your core warmer, it signals the brain to send more blood to your extremities, so in a way, the heat exchanger mask is a handwarmer too. Not that I want to discourage you from buying a pair of the pogies I make by hand.
What About Medical Benefits?
We’ve all heard about the dangers to lungs and airways of breathing extremely cold air. I am not a physician, nor do I play one on TV. I am way too lazy to do the research as to what medical benefits these masks may give to users. Even if it were no medical benefit, I would still use one for comfort and for warmth. Airtrim and Lungplus have some medical articles on their sites that I have not read.
Updated testing (Feb 2021)
At -25ºC, I have now done some more objective testing with my 3 favourite (and available) heat exchangers. After 5 minutes outside, breathing through my mouth, I measured the air temperature inside my mouth. The Airtrim Asthma filter was warmest (12º), Then the Ergodyne (10º), then the Airtrim Sport (9ª), followed by the AirTrim racing filter (7º), and finally the Lungplus (5º). For reference, I measured using a blue surgical-style mask (-5º), and no mask at all -10º). The blue surgical mask was way better than nothing at all, a full 5º warmer, but the remaining masks were another 10-17º warmer. I did not do anything more strenuous than walk in a circle for this test, and results could be different for exercise.
Feb 10: further testing, since some people have recently questioned me about the Cold Avenger, I measured, and it performs somewhat worse than a buff or blue surgical mask. The Cold Avenger balaclava is very warm, and for those mostly looking to keep moist cloth off their face and have a balaclava, it may be a good chooice.
Lungplus sent me free product in about 2000 with no conditions attached. I have purchased all the other products myself with my money. At the time I am writing this, I derive no benefit from sales of any of these devices. edit: I now have an amazon associate link for the Ergodyne 6970. I have received no money for this review, but I won’t turn down offers of free product. Edit: I also now have this Amazon Associate Link for the Airtrim Mask.