
This spring-loaded pressure valve helps prevent oxygen or water from flowing back into a CPAP or BiPAP machine when the machine is turned off. When the CPAP machine is operating, the valve allows air to flow normally through the system. When the pressure is eliminated, the valve seals and diverts any excess oxygen or water out of the system through its vents. Respironics recommends using this pressure valve whenever using oxygen or an external humidifier with their CPAP machines.