Chapter 2: Humidity is Your Superpower

There are 3 main functions of our nose and upper airway (everything above the vocal cords): Heat, Humidify and Filter the airflow heading for your lungs. We’ll get into the filter part later.
Once air enters your airway, before your lungs, your body exerts energy to heat it up to body temperature and humidify it to 100% relative humidity, which is the highest amount of water content that can be held at that body temperature.
When breathing normally, we can accomplish this by staying hydrated, mostly from drinking water.
Because CPAP therapy delivers airflow at a higher velocity, it is important to supplement that airflow to prevent cracked lips, nasal infections, dry mouth, dry throat, nosebleeds, etc.
But here’s some cool news: if you weren’t using CPAP therapy, and you wanted to calibrate the humidification levels in your environment for sleeping comfortably, exactly the way you desire, it takes a greater amount of work that is more wasteful and less accurate. Picture changing an entire room’s humidification levels by cubic feet vs the cubic feet of the inside of your CPAP tubing.

Remember 2 key points for optimization:
The hotter the air temperature, the carrying capacity of water in the air goes up.
The colder the air temperature, the carrying capacity of water in the air goes down.
Let’s say the air temperature is 97°F (36°C), plus the relative humidity level is 100% at that temperature. Suddenly there is a temperature drop to 93°F (34°C). Because the lower (93°F) temperature has a lower carrying capacity of water, it begins to rain. This is exactly why water droplets or rainout occur inside your CPAP tubing.
One thing you can do to minimize this issue, immediately, is to have your CPAP machine placed in a position lower than your mask and tubing. This way, when and if water droplets do occur, they will roll back into your humidifier chamber, rather than toward your face.
Tools to Upgrade Your Humidification on CPAP Therapy:
Distilled Water – This is the recommended option since it is water in its purest form. I have an AirSense 11 by ResMed right in front of me, and it says on the water chamber: Distilled Water Only. The reason is that it prevents calcification and other growth that could occur if you use tap water. Without using it can make it much more difficult to clean over time, especially if you are on the go. Different cities have different levels of minerals or particulates in tap water. You can buy distilled water for cheap in some places, or you can also invest in a countertop distiller. It is the cleanest, safest form of water you can use. Oh and don't be fooled, distilled water goes through a distilling process, not filtration

Here are some options: 
Buy it already distilled: Distilled H2O on Amazon
Distill it on your own: Countertop H2O Distiller on Amazon
Heated Humidifier – Most modern home CPAP machines (not travel) have a built-in heated humidifier. Below are links on exactly how to adjust your heated humidifier, also known as climate control:
           ResMed AirSense 11 – Heated Humidifier Setup
           ResMed AirSense 10 – Heated Humidifier Setup
           ResMed S9 – Heated Humidifier Setup
           Philips DreamStation 2 – Heated Humidifier Setup

Heated Tubing – Most modern CPAP machines come with a heated circuit which maintains a consistent temperature, end to end on CPAP tubing. Below are links on exactly how to change your heated tubing settings:
           ResMed AirSense 11 – Heated Tubing Setup
           ResMed AirSense 10 – Heated Tubing Setup
           ResMed S9 – Heated Tubing Setup
           Philips DreamStation 2 – Heated Tubing Setup

CPAP Hose Cover – The 3 C’s of CPAP Hose Covers. Condensation: hose covers help protect tubing from environmental temperature changes and maintain a constant temperature in the tubing, reducing water droplets. Comfort: hose covers are much more comfortable to rest your body against if needed, and they won’t leave corrugations from CPAP tubing on your face in the morning. Cats: The number of users and reviews that tell us their hose cover protected their tubing from a cat who would otherwise bite into their tubing normally was shocking.
           CPAP Hose Covers on Amazon
HME – Last but not least, is an HME, also known as a Heat Moisture Exchanger. An HME looks like a slightly larger in-circuit filter, that recycles your exhaled (humidified) air by capturing it when you exhale into the HME. This is how the AirMini travel CPAP works without a heated humidifier, and it can also be a solution for a home CPAP if you don’t have immediate access to a heated humidifier.
           ResMed AirMini HumidX (HMEs) on Amazon
           Home CPAP HMEs on Amazon

Having a basic understanding of humidification can help you calibrate it to a level, potentially more comfortable (from a humidification point of view) then breathing without CPAP therapy.


Email us:

Call us: 1 (888) 709-7377



Brady Nelson RRT
President, resplabs