Introduction

When laying down performance requirements for measuring devices to be used for legal metrological control, OIML Technical Committees and Subcommittees need to make decisions as to the extent of these requirements and the severity of the tests to be performed so as to guarantee the quality of a measurement and to reduce disputes over the results.

With the growing complexity in interconnections of measuring instruments and systems, the degree of legal metrological control that is required must be observed in a more detailed way.

Systems containing multiple measuring devices can easily grow to the size of large networks of devices when one takes into account all the interconnections; legal metrological control over such extensive networks is not readily feasible. In order to monitor the metrological aspect of such systems it is necessary to restrict legal metrological control to only those parts of a system that could influence the measurements and parameters which form the basis of a legal transaction. But restricting legal metrological control to only the primary measurement action itself may be insufficient, for example in those cases where this primary result is not recorded in such a way that its original value can be reproduced from recorded results and/or data.