The DKD Calibration Certificate documents officially the traceability of measuring results to national and international standards as required by the standards DIN EN ISO 9001 and ISO/IEC 17 025 for the monitoring of measuring instruments. A major difference between works calibra-tion services and DKD-laboratories is the accurate determination of the respective uncertainty of measurement guaranteed by the accredited laboratory and supervised by the PTB. DKD Calibration Certificates are appropriate in uses in which calibrations of an accredited laboratory are requested, where high level calibrations are demanded and for calibration of reference standards and instruments for comparative measurements.

The DKD is a member of the European Cooperation for Accreditation (EA). A multilateral agreement assures obligatory recognition of the DKD-Calibration Certificate in a variety of countries. In addition, since November 2000, 50 accreditation bodies in 41 countries – including the DKD – have signed the first international convention for reciprocal recognition, the "Mutual Recognition Arrangement" (MRA) of the International Laboratory Accreditation Corporation (ILAC). Under this convention, the subscribing bodies agree to reciprocal recognition and to promote acceptance of calibration certificates and test reports from the laboratories accredited by the signatories. (The complete text of this convention can be read on the Internet at www.ilac.org.)