Requalification and periodic review

Annex 15 requires equipment, facilities, utilities and systems to be evaluated at an appropriate frequency to confirm they remain in a state of control, and requalification to be considered where changes occur. The evaluation should use evidence rather than repeat the original studies by default.

Evidence for periodic review of a storage area

• Continuous monitoring data at the mapped worst-case locations, compared with the mapping baseline.
• Excursion and alarm history.
• Calibration history of monitoring sensors.
• Changes since the last review: racking, HVAC service, door usage, product range.
• Any seasonal extremes not covered by the original mapping.

The review concludes either that the qualified state is maintained, or that targeted re-mapping is needed — and records why.

Change control decides more often than the calendar

Most requalification is triggered by something that happened, not by a date arriving. The useful question at change control is narrow: does this change affect anything the original study established? A repainted wall does not. A new racking layout does, because the airflow that produced the mapped distribution has changed and the worst-case locations may have moved.

What periodic review should actually conclude

The review is a judgement supported by evidence, and it has to end with one of three statements rather than a shrug: the qualified state is maintained and the next review falls due on a stated date; the qualified state is maintained with a specific limitation now recorded; or the qualified state can no longer be demonstrated and targeted work follows. The third outcome is the one people avoid writing, and the reason reviews degenerate into an annual signature.

The strongest evidence is continuous monitoring data at the locations the mapping identified as worst case. If the hot spot found during qualification has been sitting at the same temperature relative to the room average for two years, the distribution has not shifted and the study still describes the room. If it has drifted by a degree, something has changed whether or not anyone raised a change control.

Targeted re-mapping

• Re-map the region that changed, not the whole building, where the change is local and the airflow boundary is clear.
• Keep at least the original worst-case positions instrumented so the new study can be compared with the old one.
• Cover the season the original study missed. A study run in February and reviewed every February has never seen the building in August.
• Write the comparison into the report. A second study that does not reference the first leaves the reader to work out whether anything moved.

An interval with no rationale behind it is itself a finding. Three years for a stable ambient warehouse and one year for a cold room holding a narrow-limit product are both defensible; the same number applied to both because it was in the SOP is not.