Review of active multitracer measurement methods.

The proposed task addresses the measurement methods using several tracer gases to measure the air flow rates between several zones of a building and between these zones and the outside air. If the building has N zones, there are N(N+1) unknown flowrates, which can be measured simultaneously using N different tracers. In so-called active methods the sampling of the atmospheres of the zones is made an active way, that is using either a mechanical pump or a manually actuated syringe or bag. For the passive methods, the sampling is achieved with an adsorbing medium contained in a cell which is desorbed and analysed later in a laboratory.