Patent attributes
New methodology, realizable with both manual and new semi-automatic imaging technology, has transformed both the inspection and the batch release Attribute Sampling Inspection for contaminating visible particles in injectable solutions into statistically replicable procedures. In this new non-destructive inspection procedure, a calibration curve relates NIST traceable measurement of maximum particle size to the rejection probability of the particle. Data for this calibration curve is determined with a graduated set of single durable stainless steel and glass microspheres that are sized with NIST traceability. Use of the calibration curve transforms the probabilistic variability of visible particle inspection data described by Knapp into the ‘simply replicable form’ required by the Attribute Sampling Tables. The present invention uses cutting edge imaging technology to achieve 1% sizing accuracy within 10 μm from 50 to 1,000 μm. An improved alternative sizing technique used in this invention uses the particle information to achieve an integral particle sizing function.
