Air leakage measurement of buildings by an infrasonic method

Describes an infrasonic method as an alternative to blower method for measuring the composite effective size of all the air-leakage passages of a building. Sinusoidally varying volumetric flows between 0.05 and 5Hz are generated by a motor-driven bellows-like source located inside the building under test. Resulting pressure variations are measured using a microphone-like sensor having an electronic signal processor. Reports system design and test results obtained to date. One house, five apartment and three interior rooms have been tested. Finds results of infrasonic tests usually agree with results of blower tests within a factor of three.