Experimental analysis of the transport of airborne contaminants between adjacent rooms at different pressure due to the door opening

Today it is common practice to try and obtain airborne contamination control through pressurization-depressurization areas. Moreover, there is some qualitative evidence that turbulence induced by the operation of a door between different pressure areas, could overcome the differential pressurization effect, and cause a pouring effect between zones, and consequently a contamination. The paper investigates the described matter through an experimental setup, with a scale physical model. Obtained results confirm that door operation is able to produce a dirty air transfer in the clean room, and that transfer entity is almost independent from differential pressure and flow rate imbalance, at least for the experimentally tested values, while it appears strongly related to air volume displaced in the door opening operation, and has the same order of magnitude of it.