Environmental monitoring: a correlation study between viable and nonviable particles in clean rooms

This article describes an environmental monitoring data study for clean rooms. Two parameters were compared in order to investigate the possibility of correlation between them: (1) total airborne nonviable (0.5 and 5 microm) and viable (CFU) particulates, and (2) surface contamination (Rodac). The investigation took into account A, B, and C classified areas, in operational moment or status, which involved "at rest" (just equipment working) and "dynamic" (equipment and operators working) conditions. Available data in the literature indicates that the parameters are not particularly dependent upon the layout or classification of areas, but rather on the use of the areas and operator behaviour. Our results showed a correlation around 0.6 between different sampling places for nonviable 0.5- and 5-microm particles. There was no correlation between nonviable 0.5- and 5-microm particles in places with laminar flow.