The micro-organisms naturally present in normal conditions in a closed environment, are not evenly distributed in the air due to the fact that they are airborne by particulates. Several factors like moisture, temperature, electrostatic charge, light, U.V., air movement, human presence, etc. influence the airborning. It is therefore necessary to perform a microbiological air test that is really representative, to consider this element.

It is suggested that, to obtain representative results of the natural microbial population, two paired air samplers or a new generation two heads air sampler should be used to have the possibility to calculate an average value. It is not a coincidence that the microbiological standards for Good Microbiology Practice report that the bacterial count test should be performed always in double to calculate the average and to obtain the true value. We forget too often that biology is not an exact science like mathematics!

The DUO-SAS-360 air sampler by international pbi has been developed with the purpose to reach this goal: a single body with two contiguous aspirating heads for a simultaneous sampling. The main performances of the instrument are: the high flow rate of 180+180 lts/m is ideal for low contamination environments. Two different media can be used for simultaneous sampling. Up to ten sequential sampling cycle for "in operation" monitoring, according to USP recommendations. 1000 litres of air in 3 minutes for faster sampling. It can be used either with RODAC or Petri dishes.