Patent ID: 8172154

Claim:
A method of monitoring the moisture content of air located in a structure comprising: A) measuring the moisture content in a sample of air at a reference location and using the moisture content in the sample of air from the reference location as a normal value, the reference location being in a position whereat air flowing into the structure is representative of the total air flowing into the structure; B) measuring the moisture content in air located at a selected location within a structure and using the moisture content in the air from the selected location as a sensed value; C) smoothing the temporal characteristics of the measured values over at least one time frame to reduce the effects of measurement noise and short term moisture transients; D) relating the smoothed sensed value of moisture content from the selected location to the smoothed normal moisture content from the reference location and defining a differential moisture content; and E) generating an alarm if the differential moisture content exceeds a preset value.