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Into the Future with Metrology - The Challenges of Digitalization

Digital Calibration Certificate - DCC

Conventional calibration certificates could soon be a thing of the past. Metrology institutes and calibration laboratories worldwide could in future use "digital calibration certificates" (DCC) instead of analog versions. Above all, machine readability would significantly support manufacturing and quality monitoring processes, where digitalization is becoming increasingly prevalent. The aim is to develop universal exchange formats throughout the metrology sector.

Basic structure of the DCC

  1. The administrative data contain information of central interest. They are indispensable for unique identification. Their data fields are therefore fixed.
  2. The range of measurement results is regulated with respect to the following information based on the SI: identifier, measured value, expanded uncertainty, expansion factor, unit and time (optional). Units can additionally be represented outside the SI (e.g. nautical miles, millimeters of mercury, degrees Oechsle). Irrespective of this, the specifications in SI always apply for the DCC.
  3. Comments and graphics are stored as far as possible without regulation. Likewise, data can be stored here in already established (or yet to be created) data exchange formats.
  4. A human-readable file, which could be modelled based on the analog calibration certificate, completes the DCC.

NEW: DCC User Forum

Starting in November 2022, PTB is offering a weekly online forum on the use and implementation of DCCs and related technologies. More information can be found Opens internal link in current windowhere.

Implementation of the DCC

The DCC is based on the internationally recognized and proven exchange format XML (Extensible Markup Language). This makes the DCC machine-readable and all information can be transferred directly and automatically to all digitally supported processes. At the same time, cryptographic signatures are used as a security procedure to ensure that the integrity and authenticity of a calibration certificate are maintained. The cryptographic procedures used at the DCC have already been tried and tested for a long time in other areas, for example in the application of the Civil Status Act (registry office), in waste management, or in the procurement system of the federal administration. Furthermore, the DCC already meets the requirements of DIN EN ISO/IEC 17025:2018-03, which is important for accredited laboratories.


A comprehensive documentation of the DCC XML schema can be found Opens external link in new windowhere. The development of the DCC is running under active cooperation of numerous organizations and persons also outside PTB. These collaborations are organized on the development platform GitLab Opens external link in new windowhere

As a result of the Opens external link in new windowDCC conference in October 2020, several working groups were formed to work with international partners to advance the development and use of DCC:

  • Digital calibration request (DCR) & Digital calibration answer (DCA)
  • Open Source Software
  • Calibration lab identification
  • Human-readable output
  • Middleware
  • Cryptography
  • International DCC infrastructure

Active participation in these working groups is very welcome. If you are interested, you can simply contact Opens local program for sending emailSiegfried Hackel.

An important element of the DCC is the representation of units and measurement data with measurement uncertainties. For this purpose, a proposal for a data model was developed in the Opens external link in new windowEMPIR project SmartCom: the D-SI. A detailed explanation and examples for the use of the D-SI is published Opens external link in new windowhere. Further development of the D-SI also takes place on the GitLab platform. There you can register yourself and with an email to Opens local program for sending emailDaniel Hutzschenreuter, be unlocked for the area to the D-SI.

Current research and development projects

BMWi GEMIMEG-II "Secure and robust calibrated measurement systems for digital transformation".

To ensure that "Made in Germany" also applies in a digitalized world, the Physikalisch-Technische Bundesanstalt (PTB), together with other research partners and companies, has launched the GEMIMEG-II project, which is funded by the Federal Ministry for Economic Affairs and Energy (BMWi) with 12 million Euros. The project will run for three years and started in August 2020. The overarching goal is to drive forward the digital transformation and strengthen the Germany economy.


More information here: Opens external link in new windowProject website


DCC Conference February 2023

The third international DCC Conference 28.2.-2.3.2023 took once again place to focus on recent developments, practical examples for digital calibration certificates and related projects.

More information can be found on the website ptb.de/dcc




  1. Siegfried Hackel, Frank Härtig, Julia Hornig, Thomas Wiedenhöfer: The Digital Calibration Certificate, PTB-Mitteilungen 127 (2017), Heft 4, Opens external link in new windowDOI: 10.7795/310.20170403
  2. Daniel Hutzschenreuter, Frank Härtig, Wiebke Heeren, Thomas Wiedenhöfer, Alistair Forbes, Clifford Brown et al. (2019). SmartCom Digital System of Units (D-SI) Guide for the use of the metadata-format used in metrology for the easy-to-use, safe, harmonised and unambiguous digital transfer of metrological data (Version D-SI 1.3). Opens external link in new windowDOI: 10.5281/zenodo.3522630