Measurements of infiltration and air movement in five large single-cell buildings.

A six channel, computer controlled, tracer gas detection system for the measurement of infiltration rates and air movement in large single-cell industrial buildings has been designed, constructed and calibrated. This has been used for over 50 sets of tracer decay measurements in five single-cell buildings ranging in size from 4000 to 31000 m³, The buildings included a sports hall, a vehicle maintenance depot, two factory workshops and an aircraft hanger. Infiltration rates and interzonal flows were derived from the tracer decay curves using methods based on multizone theory. The analysis method includes a specially developed, constrained least squares technique which gives both infiltration rate and internal flow rates. The equipment and method of analysis are briefly described, and results for each data set presented. A comparison of infiltration rates, derived from interzonal flows and from averaged tracer decay data is also given. In addition examples are given of comparisons between measured decay curves and theoretical decay curves reconstructed from the measured flow rates. Finally inconsistencies in the data and the model are discussed, together with suggestions for improvements to the experimental technique and the method of analysis.