If everything has already been internationally agreed upon, why isn't it enough to have a single state institute for the whole world? (FAQ - Quantum)
Maybe we shall see a single European institute one day, and discussion in Europe has considered this as one of a number of possible future options. Meanwhile there are several reasons for maintaining separate national capabilities:
- the current confidence in NMIs depends to a considerable extent on the collaboration and intercomparisons they carry out, and some duplication of primary standards will always be required to maintain confidence in their values and to guarantee continuity of access;
- local delivery of calibration services and metrology advice is still greatly valued by users of NMIs;
- it may prove difficult to obtain the negotiated agreements which will be required to ensure the guaranteed availability of services on demand to all users without introducing unacceptable delays or unnecessary bureaucracy;
- practical issues, such as language differences and the transportation of standards, will have to be addressed,
- in some cases, e.g. short-lived radio-isotopes, calibrations and measurements are required on very short timescales;
- it may always be necessary to maintain some national capability in all fields in case it became necessary to re-establish a full capability for reasons of defence or security.