ventilators don't just pump air. they also monitor and control the amount of air, and beep when something is wrong. plus a bunch of other features...
In any case, a standard Resmed CPAP like the one in the article has a humidifier built in, and if you buy the optional heated hose, it can heat the air too. The tank is kinda small on the humidifier, so you'd have to refill it pretty often. Probably want to hack it into having a lot more volume, if you need the humidity.
Many (most?) CPAP's do that. When you have to fill the reservoir every night you get an interesting perspective on the amount of water you breathe in eight hours.
I accidentally found out one night that I don't need the air to be humidified. That was a revelation, and one that's saved me a lot of work since.
Even at that high setting it does not affect your lungs ... the purpose of a CPAP is keep your upper airways open i.e back of your throat ... you still need to breath on your own.