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Distilled vs. Tap Water: What To Use in Your CPAP Machine

Distilled vs. Tap Water: What To Use in Your CPAP Machine

Most continuous positive airway pressure (CPAP) machines have heated humidifiers built into their designs. These humidifiers are essential to adding moisture into the air to make your mouth less dry throughout the night and morning. 

Since these humidifiers require manual water refills to run efficiently, new CPAP users are commonly confused by what type of water to use for this equipment. In this blog, we’ll share our guide to choosing between distilled vs. tap water and explain what to use in your CPAP machine. To learn more, check out the article below.

Distilled Water

The majority of CPAP manufacturers and manuals recommend using distilled water. There are several reasons why manufacturers prefer distilled water over tap water, and the number one advantage is safety. When you use bottled, distilled water, you ensure that zero microbes or chemicals are present in your humidifier’s water.

When traveling, using distilled water is even more crucial. Unfortunately, the quality of your tap water can vary depending on your location. Luckily, distilled water is a standard product sold at most grocery and drug stores.

Most manufacturers also assert that using distilled water will elongate the use and life of your CPAP machine.

Tap Water

According to the FDA, tap water is only safe to use when cleaning your CPAP machine. Of course, you should dry your equipment before use; however, the type of water used for cleaning your equipment should not affect the safety or quality of your CPAP machine. If you do not have distilled water for your CPAP machine, manufacturers recommend boiling and cooling tap water before using it. 

What To Consider

Now that we’ve outlined the differences between distilled and tap water, how should CPAP users know what to use in their CPAP machine? The key to deciding between these two types of water is weighing safety. The water that you add to your CPAP machine will produce steam that you inhale as you sleep. So it’s crucial to make sure that the air you’re breathing at night does not contain harmful bacteria or microbes.

The safest option you can use for your CPAP machine is distilled water. This filtered water will eliminate microbes and bacteria so that you can have peace of mind while you sleep. If you prefer to use tap water for your CPAP machine or have concerns about using distilled water, speak with your doctor immediately. 

We hope our guide to understanding these two options for your CPAP humidifier has been helpful. Here at Nationwide Medical, we offer CPAP equipment and advice to help you manage sleep apnea successfully. To learn more about our company and equipment like our CPAP machine filter replacements, check out our CPAPnation website.


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