A four zone ventilation test facility.

This paper describes a laboratory model for the testing and validation of tracer gas measurement techniques. Previous attempts at experimental validation have often been limited to two zones, or a particular measurement strategy, or a particular range of flows. The model consists of four zones, each of 1m³ internal volume. The zones are connected so that all possible inter-zone flow paths exist. The flow down each path is driven by a pump and monitored by a flow meter. A control panel enables any combination of interzone flows to be set, within the capacity of the pumps. By the application of scaling, one can also represent real buildings in which the zones are not of equal volume. The model may be used to validate tracer gas measurement techniques for the extraction of inter-zone flows and for the determination of Ventilation Effectiveness parameters. In principle, the model can be used with any tracer gas injection strategy and any tracer gas measuring method. Examples are given of the use of the model in exploring these parameters.