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.

