This is a method for the determination of the overall airtightness of building envelopes. It is not a method for determining the actual air leakage which occurs through a building envelope under the natural influences of wind and buoyancy pressures, or as a result of pressures produced by the operation of air handling systems.

This method is applicable to buildings with air handling systems.

The testing and evaluation of a product against this standard may require the use of materials and/or equipment that could be hazardous. This document does not purport to address all the safety aspects associated with its use. Anyone using this standard has the responsibility to consult the appropriate authorities and to establish appropriate health and safety practices in conjunction with any existing applicable regulatory requirements prior to its use.