World Metrology Day: 20 May
- The World Metrology Day is observed on 20 May to celebrate the International System of Units.
- Metrology is the study of measurement.
- The theme for World Metrology Day 2021 is Measurement for Health. The theme aims to create awareness of the important role measurement plays in health, and thus in the wellbeing of every one of us.
- 20 May marks the anniversary of the signing of the Metre Convention in 1875, by representatives of seventeen nations.
- The World Metrology Day project is currently realized jointly by the International Organization of Legal Metrology (OIML) and Bureau International des Poids et Mesures (BIPM).