I need your help for establishing alert and action limits for purified water and when the most results are less than 1. Are Statistic applicable? And if action limit according to SPEC is 100CFU/ml , how to define action and alert level?
Usually in a good designed and operated purified water system results of routine assay are much lower than the specification limits so the statistical analysis does not help to define the warning and action limits, that’s why you should to select some values that represents fixed percentage of specification limits to use during your EMP and validation program. For example 40% of spec limit as alert limit and 60 or 65% as action limit