What is CPAP rainout? Is CPAP rainout dangerous? In this blog, we’ll talk about the cause of CPAP rainout, prevention methods, and solutions to keep your CPAP device clean and condensation-free.

Moisture is the Catalyst for CPAP Rainout

When using a CPAP machine, some people will experience dry nasal passages, sore throats, nasal congestion, or nosebleeds from the continuous flow of dry air through the mask when they sleep. Heated humidification introduces moisture to the airflow, reducing the side effects of dryness and improving patient compliance. While the heated humid air can increase comfort while using the CPAP machine, it can also cause an entirely new problem due to the temperature difference between the air inside the CPAP device and that of the bedroom. Without an even temperature balance, condensation is going to form.

What is CPAP rainout? 

CPAP rainout is essentially caused by warm, humid air cooling inside the CPAP hose and forming condensation. This condensation builds up in your CPAP hose and then your mask, which in turn causes an uncomfortable feeling of dampness, ‘rain’ dripping onto your face during sleep, and/or a gurgling noise in the tube, all of which can wake you up pretty quickly. That’s CPAP rainout, and it’s a common problem in CPAP devices with heated humidity functionality to improve comfort and air quality. When the CPAP humidifier is on the highest settings, CPAP rainout is almost inevitable. 

Is CPAP rainout dangerous?

Remember, all night long, you’re breathing the air that’s circulating through the machine, so it’s essential to make sure it’s as pure and clean as possible. Aside from the uncomfortable sensations associated with CPAP rainout, the phenomenon itself isn’t particularly dangerous unless you neglect regular cleaning of your CPAP device and accessories. 

Water is a breeding ground for bacteria, so keeping your CPAP mask and hose clean is essential for all CPAP users. Just think about it. While the tubing, your mask, and other parts of the device might look clean, all sorts of nasty germs, mold, dust, and bacteria can and will build up inside, putting you at risk for developing respiratory tract irritation or even a respiratory infection. 

CPAP Rainout Prevention

Luckily, CPAP rainout prevention is relatively simple. Here are a few CPAP rainout solutions to help avoid or even eliminate CPAP rainout.

1. Move your CPAP machine to a surface that’s on a lower level than your mask. Yay, gravity! Moving your machine onto a lower surface means that if water droplets do form, they will flow back down to your device humidifier and not up into your mask. 
2. Use heated CPAP tubing. Heated tubing helps to keep the temperature of the air constant as it travels from the CPAP device to your mask. If the air stays warm, it doesn’t condense into droplets, so they can’t rain onto your face!
3. Wrap your CPAP hose to keep the air warmer. Specially designed CPAP hose wrappers can help insulate the device’s airflow into the mask from the lower temperature of the bedroom, reducing rainout incidents. 
4. Adjust your humidifier settings. You can make small incremental adjustments, but it’s best to consult with your sleep specialist before making any drastic changes. Generally, the best humidity level setting is three. 
5. Choose a CPAP device with automatic adjustment features. Many newer CPAP devices feature built-in climate control features that constantly monitor and adjust the temperature of the air in your mask and tubing for an optimal treatment experience.