Frequently Asked Questions - Humidification


Click on the questions below to view the responses regarding Humidification.

What are the overall benefits of humidification?

Up to 40% of PAP users experience nasal congestion and dryness of the nose and throat. These symptoms can be severe enough to prevent patients from continuing their treatment. The HumidAire 3i heated humidifier adds moisture and warmth to the air delivered by a CPAP or bilevel system. This reduces symptoms of dryness and congestion, improving patient comfort and compliance. Research also shows that nasal resistance can promote mouth breathing, which in turn leads to additional dryness. Heated humidification can prevent the large increase in nasal resistance that results in mouth breathing and leaks.

How much water should a humidifier use during a night?

The amount of water needed varies from one humidifier to the next, from one patient to the next, and with the temperature and humidity of the bedroom.

Why does the amount of water used vary so much night to night?

Mouth breathing or mouth leak. can make you use more water from your heated humidifier.  All the escaped air through the mouth (which can vary from night to night), uses up the water more quickly.

I have a full face mask; will I need more water during the night?

A full face mask should not change the amount of water used each night. If you had a mouth leak before, you could have been losing lots of air and humidity through your mouth, in which case you should use less water now.

I can't use my humidifier during some nights because my hose fills up with water condensation. What can I do about it and why does this happen?

This condensation is called "rainout." If your room is cold, the warmed, humidified air hits the colder room temperature and cools. When air cools, the amount of humidity (water vapour) that it can hold is reduced, which causes the humidity to "rain out." The amount of water air can carry varies with temperature: warmer air can carry more water while cold air can carry less. As warm air becomes cooler (eg, overnight), it has less capacity to carry water, so water condenses and forms droplets.

There are a couple of ways to deal with this situation. (1) You can try turning your humidity level down. (2) You can raise the temperature of your bedroom at night to lessen the difference between the room temperature and the humidifier—make sure that your bedroom window is closed. (3) You can run the air tubing beneath your blankets to keep it warm. Alternatively, you can cover the tube with our Tubing Wrap, aluminium foil or a tube sock. The goal is to keep the tube and its air warm.

I have heard that wrapping the continuous positive airway pressure (CPAP) hose with fabric will help with "rainout." Is this true?

Yes. Wrapping the hose helps to insulate your treatment air from the lower temperature of the room, reducing "rain out."

Can I put my CPAP on top of the humidifier? Or should it only go next to it?

The CPAP should always be placed either at the same level or above the humidifier to reduce the risk of water entering the CPAP machine. To further ensure water does not enter your CPAP machine, empty the water chamber and disconnect the humidifier from your CPAP machine before transporting it.

How often should I change the water in the chamber? I never seem to use it all in one night's time.

The water should be changed for each use.

Does heated humidification wear out my mask and hoses faster?

No, the tubing supplied with CPAP machines can withstand far higher temperatures than the heat generated by the humidifier.

How do I know what temperature setting to use with my humidifier?

The setting on your humidifier will set how much moisture you receive to alleviate your symptoms. The higher the setting, the more moisture, and this is best checked first with your Clinician and user manual. If you start your setting for example at a midway point, and if your symptoms are not resolved, you may need to turn it up another setting. Continue in this manner until your symptoms are resolved. If you start to experience moisture in the mask tube, you need to turn it down, heat the room or use our Tubing Wrap.

How often do I need to clean the water chamber on my humidifier?

It is recommended that you wash your humidifier and tubing daily in warm water, using a mild detergent. Rinse them thoroughly with clean water and allow them to dry away from direct sunlight. Inspect the water chamber weekly for wear and deterioration. Replace the water chamber if any component has cracked, become cloudy or pitted. If you notice white powder or deposits in the water chamber: (1) Fill the water chamber to the maximum water level and mark with a solution of one part vinegar to ten parts water (2) Let the solution soak for ten minutes (3) Discard the solution and rinse the water chamber with clean water.

Should I turn on my humidifier before I go to bed to make sure the water is warm first?

If you find the air dry and irritating, then you may want to turn your humidifier on 20 minutes prior to going to bed.

I usually use my humidifier during only the winter months when the heat is on in our house and, therefore, the air is dryer. Am I shortchanging myself? Should I be using it all year round?

If you are finding that you have nasal symptoms at other times of the year, then you should probably use your humidifier. The added humidification will probably increase the comfort of the air as it is more fully moisturised.

What are the benefits of using a heated air humidifier vs. cold? Nasal pillows vs. mask? Which is a better choice when using humidification?

Because you can adjust the level of heat, heated humidification offers greater flexibility and reduces more severe symptoms. Both nasal pillows and masks are a viable option when using humidification; however, "rainout" (moisture caused by having the humidifier turned up too high) when using nasal pillows may become more of an issue as the moisture is directed into the nostrils.

Is humidification helpful for Upper Airway Resistance Syndrome (UARS)?

Humidification doesn't really help with OSA or UARS. It helps with side effects caused by CPAP. If you are already on CPAP treatment and experiencing nasal dryness/symptoms, then humidification should help decrease the symptoms. The nasal symptoms are due to the increased flow of air through the nasal passages. Humidification adds moisture to the air breathed and helps the nasal passages cope with the increased flow of air.




Do you have a question you would like answered?

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If you have a specific, individual health concern—especially one related to your treatment—please discuss it directly with your health professional.