Why bump up a thread that's over 2 years old?smallwoodst wrote:BEWARE.BTW, distilled water is by definition pure water, and therefore sterile
Yes Distiled water is pure at some time and if kept in a serile "closed" system. Your humidifier is neither closed nor sterile
Distilled water bought in grocery stores is not usually sterile. Even if it was sterile at some point, the bottling facilities are not usually sealed well enough to stay sterile.
However, bacteria cannot multiply in pure distilled water. Whatever bacteria falls into it may live, but they can't create more bacteria.
Like any other living organisms, bacteria needs food as a source of energy and material to build new copies of itself in order to reproduce. In pure distilled water, there is no food. If there are small amounts of germ food, the germs can grow until they use that food up.
Store bought distilled water will have some germ food in it. So will whatever dust makes it through the filters on the machine. This will accumulate over time as the water evaporates, so it's a good idea to dump out the water, wash the tank and refill occasionally. If you start with distilled water, the concentration of germ food will be lower.
Even if germs grow in the tank, it's hard for them to get into the airstream, through the hose and into your mask. Water evaporating from the tank will not carry germs with it. Unless the water tank is spraying droplets into the air stream, the germs find it hard to get out of the water and into the air stream.
I still want a clean water tank, but you don't need to be fanatical about it.
Don't forget the air we breathe all the time has germ in it anyway. If anything, the CPAP air will probably be cleaner due to the air filters on the back of the machine.
