The inflow air impacts in the surface of
the culture media, chosen on the basis of the microbiological investigation to be carried out, placed
in a 90 mm Petri dish. At the end of the sampling period the Petri dish is removed and placed into
an incubator. At the end of the incubation it will be possible to count the CFU/cm2 and evaluate the
air biocontamination level of the critical area on the basis of air volume sampled .