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The International System of Units - Fundamentally better

Celebrating World Metrology Day

World Metrology Day, on 20 May, is an annual anniversary celebrating the science of measurement, its achievements and the passionate community working in this field.

Across the world, National Measurement Institutes and Designated Institutes work to advance measurement science by developing and validating new measurement techniques to ensure that accurate measurements can be made everywhere.

World Metrology Day commemorates the anniversary of the signing of the Metre Convention in 1875. This treaty provides the basis for a coherent measurement system worldwide that underpins scientific discovery and innovation, industrial manufacturing and international trade, as well as the improvement of the quality of life and the protection of the global environment.

The theme for World Metrology Day 2019 is The International System of Units - Fundamentally better. This theme was chosen because on 16 November 2018, the General Conference on Weights and Measures agreed perhaps one of the most significant revisions to the International System of Units (the SI) since its inception. Research into new measurement methods, including those using quantum phenomena, underpin the change. 

This change comes into force on World Metrology Day and the SI is now based on a set of definitions each linked to the laws of physics. This has the advantage of being able to embrace further improvements in measurement science and technology to meet the needs of future users for many years to come.

EURAMET members, through the European Metrology Research Programmes (EMRP and EMPIR), have contributed greatly to the scientific basis for the redefinition.

Find out more about the SI redefinition, the SI units and discover how the EURAMET community has contributed to this fundamental change at EURAMET's SI redefinition web pages.

World Metrology Day website
World Metrology Day is jointly organised by the International Bureau of Weights and Measures (BIPM) and the International Organisation of Legal Metrology (OIML) with the participation of the national organisations responsible for metrology.

Further information, including a message from the Directors, posters, and a list of events can be found at the World Metrology Day website for download.


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