A Continuous Positive Airway Pressure (CPAP) machine often includes an integrated humidifier to prevent dryness and irritation in the nasal passages and throat. This component adds moisture to the pressurized air delivered during sleep. The quality of the water placed in the reservoir directly impacts the safety and effectiveness of CPAP therapy. Choosing the correct water type protects both the user’s respiratory health and the longevity of the machine.
The Essential Choice: Distilled Water
The definitive recommendation for CPAP humidifiers is distilled water, a choice rooted in its purity. The distillation process involves boiling water into steam and then condensing the steam back into liquid form. This action leaves behind nearly all dissolved solids, minerals, and contaminants.
Manufacturers recommend this water type because it prevents the formation of “scaling” or limescale on the heating plate and in the water tank. Mineral buildup reduces the humidifier’s efficiency, forcing the device to work harder to heat the water and provide the intended humidity. Distilled water ensures the machine operates as designed, maintaining optimal air pressure and humidity output without internal obstruction and extending the functional life of the CPAP unit.
Risks of Using Unfiltered Water
Utilizing tap water, filtered water, or bottled spring water in a CPAP humidifier introduces two primary risks: equipment damage and potential health hazards. Tap water contains minerals like calcium and magnesium, known as “hard water.” When heated, the water evaporates, but these non-volatile minerals remain and concentrate. This results in calcification, which impairs heating efficiency and may void the machine’s warranty.
The second concern involves health risks from inhaling aerosolized contaminants. Tap water, while safe to drink, may harbor trace amounts of microorganisms like bacteria or fungi. When heated and converted into a fine mist by the CPAP, these microbes are delivered directly into the user’s respiratory system. This exposure can lead to respiratory irritation or severe infections. Furthermore, chemicals added to municipal water, such as chlorine or fluoride, can also be inhaled when aerosolized, causing irritation to the lung tissues.
Water Reservoir Maintenance and Handling
Proper handling of the water reservoir is just as important as the type of water used. Users should change the water daily, even if a small amount remains, to prevent the moisture from becoming stagnant. Stagnant water creates an ideal, warm environment for any residual microbes or mold spores to multiply.
Routine cleaning is necessary to maintain a hygienic environment inside the tank. The humidifier reservoir should be washed weekly with a mild, non-abrasive soap and warm water, followed by a thorough rinse. Alternatively, some manufacturers recommend soaking the chamber in a solution of one part white vinegar to three parts water to help dissolve any early mineral deposits.
If distilled water is temporarily unavailable, such as during travel, a short-term alternative is to use sterile water or tap water that has been boiled for at least five minutes and cooled. This boiling process kills any present microorganisms, although it does not remove minerals and should not be a long-term practice. If a temporary substitute is used, the reservoir must be cleaned immediately upon returning to the regular supply of distilled water to prevent mineral buildup.