Calibration minimizes uncertainty by ensuring that the test equipment output is within the allowable accuracy range. After any calibration exercise, a certificate is mandatory.
The calibration certificate is an official document that gives evidence of instrument calibration. Through the certificate, pne can maintain device traceability. ELPRO provides a calibration certificate for data loggers because it validates any calibration claims and provides credibility.
One will find crucial information about the logger's working condition within the document, including out-of-tolerance details. Although the certificate contents will vary according to geographical location, important details include calibration dates, traceability statement, the calibration procedure, and interval. The document should also state clearly the standard used for the calibration process.
The calibration procedure for a cold chain data logger involves both temperature and, when applicable, humidity checks. For temperature calibration, a bath is necessary to allow the logger and the calibrator to come to the temperature point.
A humidity generator provides a reference value during humidity calibration. If the logger's temperature and humidity values do not correspond to the standard, an adjustment may be necessary or a replacement according to the perceived discrepancies.
Calibrating a data logger begins with inserting the device under test and the reference into the same environment. After some time, one can make comparisons of the readings from both devices. If the difference is more than the allowable tolerance, then readjustments must follow.
The process continues until the deviation falls below the tolerance limit or there is no deviation at all. One should include all the calibration documentation adjustments to provide an accurate establishment of the adopted calibration procedure.
If there is a need for repair, the final documentation must show why, how, and what initiated the repair. It must also report on the success or failure of the endeavor. Hereafter, the issuance of a calibration certificate follows for the particular data logger.