My wife has an ozone cleaner for her CPAP. It might be the SoClean2 model you are looking at, not sure off the top of my head. I wish she had at least talked to me about it before getting it because I’m not convinced it’s really all that useful.
Ozone doesn’t clean anything. It’s not a cleaner. If there is some kind of crap on your mask, at the end of the cleaning cycle there is still going to be some kind of crap on your mask. The ozone isn’t going to remove anything.
Ozone might disinfect your mask. Emphasis on “might” because I have some doubts about how effective it is for this type of cleaning unit. The principle is sound enough. Ozone does kill bacteria and viruses. Ozone has been used in wastewater treatment for years.
The reason I am skeptical is because I don’t know how much ozone this machine actually produces, and whether or not it creates a high enough ozone concentration inside the machine, and if it maintains that concentration long enough to be effective.
Whether or not the machine is producing enough ozone to be effective, one thing I can say is that the machine does not leak enough ozone into its surroundings for the ozone to be an issue. According to the folks that make these types of machines, ozone decays fairly quickly back into oxygen, so by the time the cleaning cycle is done there isn’t much ozone in the machine to worry about anyway. Ozone has a fairly distinctive smell, and I haven’t smelled it at all anywhere near the machine, which seems to confirm their claim that the machine leaks very little ozone into its surroundings.
The alarmist warnings on the internet are correct that high enough concentrations of ozone do cause health issues, particular with breathing. However, this machine just doesn’t seem to release enough ozone into its surroundings for it to be worth worrying about.
I have no experience at all with the UV machine. I do know that UV has a tendency to degrade most types of plastics. The UV in sunlight is what causes things to fade if left outdoors, and in addition to fading, it can make plastic brittle, leading to cracking. Some plastics have UV stabilizers added to them, which basically work by preferentially absorbing the UV and releasing it as heat (kinda the same way that sunscreen works on our skin). I very much doubt that the plastics used in a CPAP machine have UV stabilizers in them since CPAP machines are rarely used outdoors in sunlight.
The theory for UV is also sound, as UV light does kill bacteria and viruses. I have no idea how much UV light the machine puts out. I suspect that if it puts out enough UV light to be effective at killing bacteria and viruses, it also has enough energy to degrade any non-UV stabiliized plastics put inside the machine.