N. 82 - Sampling viable organisms by microbial active air samplers

IMPORTANCE OF THE IMPACTION ON AGAR SURFACE. Effect of jet velocity, nozzle size, nozzle distance from the agar surface, quality of medium, volume of medium inside the culture, expiration date of the plate, moisture content and sterility of the medium, temperature should be considered to obtain the optimization of these variables. These facts are determinative to obtain an efficient design of a microbial air sampler. ISO-14698 standard mentions that impaction velocity should be less than 20 metres per second.