3 ms·

All masks come equipped with an anti asphyxia valve. They are a very simple flap that fails open in the case of a power outage or other failure, a (C|A)PAP mask

• ars 14y ago
  Only full face masks do. The nasal ones don't. Technically you could breath through your mouth if there was a problem, but some people have issues keeping themself from breathing through their mouth, so they use a chip strap to prevent it. And then this hazard comes into play. And you entirely missed my point. The masks are safe because someone thought of the hazard and designed against it. If you are making things homebrew you better make sure you are aware of all the hazards.