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Most Probable Count (MPC) in Environmental Monitoring

In pharmaceutical cleanrooms and controlled environments, active air sampling is a critical component of environmental monitoring. It ensures that airborne microbial contamination remains within defined limits, protecting product sterility and patient safety. During active air sampling, microbial particles impact a nutrient agar plate through a grid of holes in samplers such as slit-to-agar samplers or RCS (Reuter Centrifugal Sampler). However, the raw colony count on the agar plate often underestimates the actual number of microorganisms in the sampled air because multiple particles can impact the same hole. This is where the Most Probable Count (MPC) and Feller correction come into play. 🌿 What Is Most Probable Count (MPC)? The Most Probable Count (MPC) is the statistically corrected number of microbial colonies in a given air volume during active air sampling. It accounts for the possibility of multiple particles hitting the same hole or impact site on the agar surfac...
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