As part of a maintenance review, a ZES consultant realised that a sterile isolator's independent environmental particle counter sensor's 'As Received' calibration tolerance limits, set by the Supplier, were actually outside those as stated by ISO-21501.

After speaking with the Supplier, it turned out that the Supplier had decided to allocate a ±10% tolerance (100% extra) for 'As Received' (Supplier Terminology) calibration values and then would adjust back to within the ISO standard of ±5%, without issuing an Out of Calibration Certificate or even formally notifying the Life Science Organisation.

Only on the 'As Left' Calibration Certificate did the Supplier's Calibration Certificate clearly state 'This calibration complies with the requirements of ISO-21501'.

In the experience of the ZES consultant, other Clean Room Environmental Monitoring System Suppliers comply with the ISO Tolerances for their 'As Found' or 'As Received' calibration tolerance criteria.

ZES find it astonishing that a Life Science Supplier should just decide to apply their own criteria, which differed from the ISO standard, for 'As Found'or 'As Received'calibrations.

The Calibration Certificates were reviewed and accepted by a non-technical representative of the Life Science Organisation, who had very little understanding of calibration.

For the benefit of the reader: 'As Found' and 'As Received' calibration checks are the same (calibration check before adjustment). Different organisations use different terminology.

Do you really know what your suppliers are doing on a technical basis?

If your organisation would like a maintenance or calibration review contact ZES.