Validation tests for a passive tracer gas technique.

In the frame of a Swiss research project, a passive tracer gas technique for the determination of multizone air flow and contaminant transport in buildings was tested, based on previous work in several other countries. First emission characteristics of the three different sources (PMCP, PMCH and o-PDCH) and the adsorption characteristics of the passive samplers (standard Perkin-Elmer AD400 adsorption tubes) were established. Then, tests were conducted in a 85m3 air flow chamber in order to determine the influence of the source and sampler position in the room on the concentration measurement accuracy. Tests were made with constant and variable air flow and temperature conditions. First results showed a non-negligible influence of sinks for these tracer gases in the air flow chamber. Additional tests then showed, that sink problems may also to be expected in typical office or residential building rooms. The paper gives an outline of the research project, summarises the results of these first tests and discusses the influence of the findings on the applicability of the method.