Typical requirements suggest 1,000 litres per air sample in high risk areas, such as: grade A filling lines, grade B clean rooms, operating theatres etc. As the criticality of the area reduces, the sample size can be reduced. The aim is to achieve a representative sample; so where higher counts would be expected, a smaller sample produces a more realistic number of cfu to count.

SAS samplers were originally designed for Contact plates, however, a Petri dish option has been available for a number of years. It is really a personal choice, although this should be decided at time of purchase, as the sampler will be specifically configured for the plate type chosen. There are advantages for each version and we would be happy to discuss your specific needs.

Settle plates are used to monitor the level of viable particles in the environment through a process of passive air sampling. A viable particle settles on agar plates at a rate dependent on its characteristics and the airflow in the environment.

EU GMP Guide Annex 1 has recommended that 90mm settle plates can be exposed in cleanroom environments for up to 4 hours. However, agar plates may dry out during long exposures where the rate of air exchange is high. So, it might be necessary to use deep filled settle plates, or replace the settle plate after a shorter time to ensure satisfactory growth promotion after exposure.

General purpose media have nutrients that support the growth of most non fastidious culturable microorganisms.

Selective growth media contain components that will inhibit the growth of some types of microorganisms, while supporting the growth of others.

General purpose media, such as Tryptone Soya Agar, are used to produce total counts. While selective media, such as XLD for Salmonella species, are used to test presence/absence of specific types of microorganism.

No, do not put your SAS sampler in a steam autoclave. The only part that can be autoclaved is the drilled head. The unit can be wiped with alcohol wipes to decontaminate it. The only other exception is the SAS Pinocchio, parts of which can be autoclaved.