National Physical Laboratory

Worldwide Metrology

The need for accurate measurements is evident throughout history and an internationally agreed metrology system is vital for innovation, trade, quality of life and effective regulation.

Worldwide metrology at the highest level operates through a well-established network of National Metrology Institutes (NMIs) and Designated Institutes (DIs). Since it was established in 1900, NPL has been an active player on the international metrology scene.

People round the world
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The central coordination role for worldwide metrology is undertaken by the Bureau International des Poids et Mesures (BIPM), with individual countries represented by National Metrology Institutes (NMIs). NPL is the prime NMI laboratory for the UK, along with LGC and TUV-NEL, the other institutes within the UK National Measurement System (NMS). The National Measurement Office (NMO), an Executive Agency of the Department for Business, Innovation and Skills (BIS), is responsible for managing and developing the NMS and is also responsible for legal metrology. Some key activities are undertaken by the NMIs on a worldwide basis under the auspices of the CIPM, whilst others are undertaken on a regional basis (e.g. within Europe) and are organised by the Regional Metrology Organisations (RMOs). EURAMET is the RMO for Europe.

Find out more about these key organisations (BIPM, NMIs, RMOs and EURAMET).

Vernier measurement caliper
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Key steps in the development of the international metrology system in operation today were the establishment of the BIPM and the Metre Convention in 1875, the introduction of the SI system in 1960 and the establishment of the CIPM Mutual Recognition Arrangement in 1999. Find out more about these key activities, and learn more about CIPM MRA.

Further information on metrology and the international metrology system can be found in the booklet 'Metrology - In Short ' (PDF 1.52 MB) - hard copy available on request (see contact details below).

The UK NMS is funded by the UK Government (BIS), through a number of metrology research programmes which are coordinated and delivered by the UK NMS laboratories, with the prime laboratory being NPL. In particular the NMS International Programme was established in order to ensure a coherent and strategic approach to International issues.

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For further information, please email International Enquiries


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