General information

PTB promotes the international cooperation in legal metrology. A key objective is the harmonization of metrology. In the field of legal metrology this is achieved by co-operation in the OIML (International Organization of Legal Metrology).
Germany is a founding member of the OIML, which was created by an intergovernmental Treaty signed in 1955. Membership of the OIML now stands at 127 Member States.
The primary goal of the OIML is to internationally harmonize the numerous regulations of the various countries and metrological tests of measurement devices, and to promote mutual recognition of test results and certificates, thus reducing technical barriers to trade in the sense of the WTO (World Trade Organization) agreement.
Uniform recommendations on requirements for measuring instruments as well as the mutual recognition of equivalent certificates support the German import and export industry. This concerns equipment that is subject to legal control such as scales and gas pumps as well as gas, water and electricity meters.
The OIML certification system aims at harmonizing type approval procedures of measuring instruments by recognizing type approvals on the basis of OIML recommendations.
An OIML certificate attests that an instument pattern has passed the necessary conformity tests specified in the relevant OIML Recommendation.
A large number of OIML recommendations are normative documents in Europe as defined in the MID (Measuring Instruments Directive) and NAWID (Non-Automatic Weighing Instruments Directive), which in turn form the basis of over 100 million calibrated measuring instruments in Germany.