AC pressurisation model tests.

Leakage area measurement by fan pressurisation becomes more difficult as the volume of a building is increased. The equipment becomes bulky, and measurements of air flow through the fan and the resulting pressure differential require more care. AC pressurisation offers an attractive alternative. However, in the case of large industrial buildings, the exterior envelope is often constructed of thin flexible sheet material, and also industrial leakage paths may have a much larger area than is found in, say, typical domestic construction. Thus theinertance effect described by Card et al (1) and the flexing constant described by Sherman (2) may be particularly important. In order to explore these problems, tests are being carried out on a laboratory model. This note reports the results of the first sets of measurements.