Only one format is chosen for microbiological validation: Usually this is the one with the lowest treatment time available i.e., the smallest bottle because it runs at highest speed and represents the most critical condition.
In agreement with both parties, also the main contractual format or the one with the most difficult shape or geometry may be selected as the validation format.
If the microbiological performance has been proven with this format all other formats perform equal or better. In this case, no further microbiological tests with other formats are required.
