1 Infrasonic impedance measurement of buildings for air leakage determination.

Reports preliminary research directed towards developing a new method for measuring the air leakage property of an enclosure. The low-frequency acoustic impedance of the enclosure is measured by an infrasonic method. Describes and analyses a diaphram-type motor-driven source and a pressure sensor with electronic filters used to measure infrasonic impedance.< Reports tests run in enclosures of different volumes and degrees of leakiness. Compares results with blower tests and finds disagreement of less than 10% for small enclosures, but for larger enclosures results differed by more than a factor of three.