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Calibration certificates go digital

Considerable added value through easy use of all calibration data at a later stage

PTB-News 2.2018
Especially interesting for

the fundamentals of digital metrology

calibration laboratories

quality management and certification

Conventional calibration certificates could soon become history. To furnish proof that a measuring instrument has been calibrated and of how this has been done, metrology institutes throughout the world could, in the near future, use digital calibration certificates (DCCs) rather than their analog version. Especially the fact that they are machine-readable speaks in favour of DCCs for production and quality monitoring processes in which digitalization is becoming ever more important. The ultimate goal consists in developing universal DCC exchange formats valid for all areas of metrology.

In industrial production, the quality of products can only be guaranteed if the measuring equipment used is calibrated at regular intervals – i.e. if it is traced directly or indirectly to the national standards. Ensuring that this is possible is one of the central tasks of national metrology institutes. In this context, calibration certificates play a decisive role in each metrological quality management system.

But digital calibration certificates can do more than just serve as a proof of metrological traceability. Since the newly developed DCC is based on the internationally accepted and approved exchange format XML (Extensible Markup Language), it is machine-readable; moreover all indications, including the numerical calibration curves, can be directly and automatically transferred into all digitally supported processes. At the same time, cryptographic signatures are used as security procedures to guarantee that the integrity and the authenticity of a calibration certificate is still ensured. The cryptographic procedures used for DCCs have proven their worth in other areas such as the civil register office (“Standesamt”), waste management or in the purchasing department of the German federal administration.

The digital calibration certificate is already being further developed: a digital twin could contain even more data and software and would thus enable the measurement process to be simulated. Physical weights already have such digital twins which have been successfully tested. This “digital weight” contains both information from calibrations and estimations concerning the expected behaviour of the weight under certain ambient conditions.


Siegfried Hackel
Project 1.01
Digitalization in the Mechanics and Acoustics Division
Phone: +49 531 592-1017
Opens window for sending emailsiegfried.hackel(at)ptb.de

Scientific publication

S. Hackel, F. Härtig, J. Hornig, T. Wiedenhöfer: The digital calibration certificate. PTB-Mitteilungen 127 (4), 75–81 (2017)