providing a sensor in {HEAD ~ a substantially fixed position} relative to the insulation in the cavity, wherein the sensor is an air cup that is pressed against {TAIL ~ the insulation} 
providing a sensor in { HEAD ~ a substantially fixed position } relative to the insulation in the cavity , wherein the sensor is an air cup that is pressed against { TAIL ~ the insulation }
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL