Oma.. Welcome to the Forums.
Your post opens a whole can of worms. First.... I'm not a doc. . I'm just a truck driver with sleep apnea who is involved with international abuse testing of cpap machines in semi trucks. So I've got experience in what you are asking about.
I will run a test cpap machine on bottled water and distilled water. I see how long it takes me to break it and why.
At home I test machines on tap water.
But to keep the legal and Irb gremlins from coming out I need to remind you that any information I give might be worth exactly what you pay for it. Nothing....
Next.... to keep the cpap machine manufacturers from getting mad I need to say you should always read and follow the manufacturers instructions for your cpap.
Ok.... now... There are other forums about sleep apnea where your question has been discussed at length.
I happen to be a big fan of America Sleep Apnea Association forums http://www.apneasupport.org/ in the Cpap machine masks. ... forum you could probably find a dozen or so threads started by other users on this topic. Stop by the Asaa forums to get a taste.
Distilled versus tap depends on how often you're going to be on changing the water, how clean is your tap water, how hard is your tap water, what make and model of cpap are you using, and do you have any medical conditions that make you catch upper respiratory tract infections easily?
The first trade off with tap versus distilled are the little bugs swimming around in any tap water. If it's pretty clean US water it's not a big deal. But if you are looking at using tap water while on vacation in Africa that might not be smart. If you dump and replace the water in the chamber every morning that helps.
I've seen some pretty bad cases of the green slymies from folks using tap water and not cleaning things.
My first winter on cpap I got a bad case of bronchitis probably from not being good about cpap cleaning.
So one vote for distilled water if you get infections easily.
The other problem is lime and hard water deposits in the humidification chamber. You can clean them out with vinegar and water. Be sure to rinse everything well.
The humidification chambers on some cpap are much easier to clean than others. ( Fisher Paykel Hc versus the new Icon) Some models have optional disposable humidification chambers (ResMed s9).
So if you don't mind dealing with lime in your humidification chamber that would be a vote for tap water.
For me I hate cleaning humidification chambers and don't like the smell of vinegar so I use distilled water whenever I can. On the other hand living on the road sometimes I run out of distilled water so I use bottled water and deal with the lime when I get home. At home I use tap water because I'm lazy and have an S9 with disposable humidification chambers.
Welcome to being a hose head.
Hope this helps.
Great information here, thanks everyone! Here's information from the CPAP care and maintenance page:
What kind of water should I use to fill my humidifier chamber? Always use distilled water because it is mineral-free. If you are unable to find distilled water, occasional use of bottled water is fine. DO NOT use tap or bottled water continuously, as it will corrode the bottom of your chamber.
Note: You should never top off or reuse the water in your humidifier. You may adjust the amount you put in the chamber if you find that you need less water.
Hi All. I spent some time today reviewing recommendations for humidification from three major CPAP equipment manufacturers, and distilled water is recommended by each for many of the reasons that have already been posted here on the forum. Water quality can vary greatly between locations, especially when traveling internationally. The process of distilling water removes many of the impurities and chemicals found in tap water or other kinds of bottled water.
Good point chillywilly. I've found myself in the situation of not having distilled water when traveling, and the smell of chlorine was overwhelming enough that I could not wear my CPAP!
Short answer is that water which is safe for drinking is safe to use in your humidifier. If you use tap water or rain water you will need to clean your chamber occasionally because it will eave deposits as it evaporates. These are harmless enough but don't look great and, if they from a thick enough layer over the heater plate, may interfere with humidifier operation. Soaking with vinegar and a scrub with a tooth brush usually does the trick. Distilled water will keep you humidifier chamber much cleaner because there is nothing in it to get left behind when it evaporates, so you may never need to clean your chamber.
However, no matter what kind of water you use, you should ALWAYS empty your humidifier chamber daily and dry it out. It doesn't matter what kind of water you use, there are yeasts and moulds floating in the air everywhere and if you leave water in your humidifier long enough they will start to grow in it. If you empty and dry your chamber daily then this is adequate to prevent growth of pathogens.
I have seen the bottom of humidifier chambers corrode, but only very rarely. It is far more likely that there was a fault in the metal responsible for this than anything else. On the other hand I've seen thousands of humidifier chambers used with tap water for years with no corrosion. Regular cleaning was all that was required.
One of the things which varies most from one model of CPAP to another is how easy it is to use, empty and clean the humidifier chamber. The best at present would be the Respironics DreamStation which has the best humidifier design I've ever seen.