This morning I upcycled a CPAP machine. This was my Mother-in-law's. These things are hard to get rid of. You cant sell them cause they are prescription. You can give them to a recycler, but I would have to pay the shipping and then they are going to "refurbish" and sell it. Then I had an idea this morning.
My new fresh air supply respirator
I pulled all the intake/exhaust flaps off to get as much flow thru as possible. It works really well. It will be even better with a longer hose. Right now it almost has too much pressure and flow.
Honestly I don't know how anyone could sleep with one of these strapped to your face(not this mask). I have empathy for anybody with sleep apnea.
From one who wore one for nearly 10 years....
Yes they suck, but so did waking up with a splitting headache like a hangover every day. I've since learnt to sleep in a better position and only wear it when it's really cold or dry so I don't get a sore throat.
A few observations from experience
1. Your tube and mask will get damp and musty, you will probably need to clean/sterilise it occasionally (hot soapy water or I used 96% ethanol spray)
2. Make sure you keep it well away from any dust and dirt when not in use because of above, or you'll end up with gunk up your tube
3. Having a mask wrenched off your face can be painful if the tube gets caught, it might pay to do something like the SCBA gear and run a hose to a belt mount/connector and then onto your air outlet (machine, fixed pipe, whatever). That way you could also disconnect if you need to temporarily without having to take it off
4. If the airflow is too much, you should be able to add an inline valve to restrict it. They're built to work against your out breath as well, so a bit of pressure shouldn't hurt it
When I first saw your post I thought it was about making a vacuum pump (I used an asthma nebuliser for a vacuum pump).
Steve