What is OUT OF SPECIFICATION
Out of Specification (OOS) refers to any analytical or microbiological testing result that falls outside predefined safety limits, official pharmacopeial standards, or internal product specifications.
Why it is happening
Laboratory Error: Incorrect pipetting, uncalibrated instruments, contaminated media, or calculation mistakes
Manufacturing Failure: Formulation errors, raw material defects, equipment malfunction, or improper environmental controls.
2 phase investigation
Phase I (Lab Investigation): Rule out analyst or equipment error. If lab error is proven, the test is invalidated and repeated.
Phase II (Manufacturing Investigation): If no lab error is found, production records and batch conditions are audited to find the root cause.

