The third part of a validation protocol for a particular piece of equipment, abbreviated “PQ.” In contrast to “operational qualification,” which tests the extremes of the performance of the equipment, PQ is designed more to make sure that your equipment performs appropriately and consistently within the “normal” range of testing in which it is expected to operate. As with all parts of validation, objective evidence is required, and this should be documented according to the validation protocol established before the equipment is installed. Other parts of the validation protocol for new equipment are installation qualification and the previously mentioned operational qualification.