A prototype semi-automated system for measuring air infiltration in buildings using sulphur hexafluoride as a tracer.

Describes a system which automatically operates a small gas chromatograph and measures parts per billion concentrations of sulphur hexafluoride in air. It samples air on a 10-minute cycle and records the response on a strip chart recorder. When SF6 in distributed in the air of a building, data is obtained from which air infiltration rates may be determined.