{TAIL ~ An air flow sensor} and pressure sensor is positioned to monitor air flow channeled to {HEAD ~ the mask} 
{ TAIL ~ An air flow sensor } and pressure sensor is positioned to monitor air flow channeled to { HEAD ~ the mask }
TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD