Qualifying a stability or climatic chamber
Chambers are qualified for temperature and humidity uniformity, stability and recovery — with acceptance criteria tied to the ICH conditions they will run.
A stability chamber must hold its set condition everywhere product is stored, for months. Qualification therefore emphasises spatial uniformity and temporal stability of both temperature and humidity, and the behaviour of the chamber under disturbance.
Study design
- Calibrated sensors at corners, centre and shelf positions — humidity sensors alongside temperature at a subset.
- Each ICH set point in use, run until stable then for a defined period.
- Empty and loaded configurations.
- Door-opening test with recovery time measured.
- Alarm tests and power-interruption behaviour.
EURAMET cg-20 describes how to characterise chamber uniformity and stability metrologically — the same methods serve qualification when paired with acceptance criteria.
Frequently asked questions
- How many sensors for a stability chamber?
- Nine positions (eight corners plus centre) is a common minimum for a small chamber, more for walk-in units; the plan should be justified in the protocol.
References
- [1]EudraLex Volume 4, Annex 15: Qualification and Validation (2015)
- [2]EURAMET cg-20: Calibration of Climatic Chambers
General technical guidance written against the cited sources. It is not regulatory or legal advice and does not replace the applicable standard, guideline or a qualified reviewer's judgement.
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