Presumptive out-of-tolerance (OOT) testing is the first step of a scientific metrological means for the quantitative assessment of the relative strength of the scientific validity of the filter during its previous calibration cycle. For our measurement model, aA presumptive OOT observation is recorded when the mean value of triplicate as-received measurements of the filter is excluded from the corresponding measurement uncertainty interval for its previous calibration. In the event of the recording of a presumptive OOT observation, rigorous post-calibration execution of science-based analysis of independent measurements to confirm or negate a presumptive OOT mean value is available at any time afterwards at an additional cost through Stranaska Scientific Documentation Services.