What actually happens during IQ, OQ, and PQ

Installation Qualification (IQ) asks one question: is what got built the same as what was designed and specified? We verify equipment against approved drawings and datasheets, check utility connections, confirm calibration certificates on every instrument that will be used downstream, and record serial numbers. Nothing is switched on and tested for performance yet — IQ is a paperwork and as-built exercise, and it is the foundation every later stage cites.

IQ asks: is it what we specified? OQ asks: does it work? PQ asks: does it keep working with real people and real product in the room?

Operational Qualification (OQ) tests the system doing its job under controlled, unoccupied conditions: airflow velocity and volume, filter integrity scans, pressure cascade across every door and hatch, recovery time after a simulated disturbance, and alarm response — does the system actually alarm when a differential pressure gauge is pulled outside its band, and does it log the event. This is where most deviations surface, because it is the first time the installed system is actually exercised against its design intent.

Performance Qualification (PQ) is the one people forget has a duration: it demonstrates the space performs to specification during actual, occupied operation, not a simulated one. That means a monitoring campaign — typically a minimum of three non-consecutive days for a lower-grade support space, extended to a full multi-week campaign with viable and non-viable particle counts for an aseptic Grade A/B suite — run while people and process are genuinely in the room.

Every stage produces a protocol (written and approved before execution, never after), raw data sheets, a summary report, and a deviation log for anything that did not pass first time with its resolution recorded. An auditor who cannot trace a straight line from IQ through OQ to a PQ summary report will not accept the dossier regardless of how the room actually performs.