With the advent of WTO systems for world trade, the equivalence of national measurement standards has become a more important issue than ever before in international metrology communities. To reduce any technical barriers caused by differences in metrological systems, the NMIs of 38 member states of the Metre Convention, along with two international organizations, signed a Mutual Recognition Arrangement (MRA) in 1999 that was arranged by the CIPM. The agreement allows the signatory NMIs to mutually recognize national measurement standards, as well as the calibration and measurement certificates issued by one another. The CIPM MRA provides transparent, reliable, peer-reviewed, quantitative information on the capabilities of NMIs and the degree
of equivalence of SI units and quantities they measure.

The CIPM MRA also provides a technical framework for several
agreements negotiated upon for international trade, commerce,
and regulatory affairs in such cases where acceptance and equivalence
in measurement results are important. KRISS has been a member
of the CIPM MRA since 1999. To meet the requirements of the global
MRA, KRISS actively participates in key comparisons (KCs) organized
by related regional and international organizations, such as the CIPM
and the Asia Pacific Metrology Programme (APMP), and carries out
peer reviews on calibration and testing services.