The MultiTracer Measurement System (MTMS) has been designed to make realtime,
multizone air :flow in buildings. MTMS injects a controlled amount of various
tracer gasses into the test space(s) and by monitoring the resultant concentration, can estimate
the relevant air :flows. The system fills the twin needs for the determination of pollutant
and energy transport. This report describes MTMS including its hardware, principle of operation, and
analysis techniques. Finally, we present results selected from its first year of operation as
an example of its capabilities.