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 - Second Edition

This guide specifies principles for determining the use of units in digitised communication of machine-readable data. These principles form the basis for all applications that transmit or require measurement data according to the specifications of the Système International d'Unités (SI). Basic principles for harmonised, clear, easy to understand and secure digital communication of metrological data are defined for real, complex, vector and constant quantities.

The metadata model described is essential for the exchange of metrological information in all fields of Information and Communication Technologies (ICT). In terms of content, the model takes into account essential international metrology guidelines and standards. For the first time, in conjunction with the globally established SI, measures are defined which are essential for an easy, secure, harmonised and unambiguous exchange of metrological data. The handling of non-SI units and the requirements for conversion between SI and non-SI quantities are taken into account.

In addition, a classification for the suitability of metrological data for interoperability and machine readability is made (medal system). The classification results from the use of SI units as defined in the 9th edition of BIPM's SI brochure.

Finally, this guide is the second edition of "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". It adds a comprehensive appendix with rules for using the D-SI and an improved reference to the XML implementation for the D-SI.