metrologii

Metrology is the science of measurement and its application across science, industry, and daily life. It covers the development and maintenance of measurement standards, the methods used to obtain measurement results, and the assessment of measurement uncertainty. The goal is to ensure measurements are accurate, reliable, and internationally comparable, enabling fair trade, scientific progress, and safe technology.

Metrology is commonly divided into scientific, industrial, and legal metrology. Scientific metrology develops and maintains fundamental standards; industrial metrology covers calibration, instrumentation, and quality control in manufacturing; legal metrology concerns regulatory requirements for measuring instruments used in trade and safety. Across these domains, traceability to the SI is central.

The SI provides the global framework for measurement, overseen by the CGPM and administered by the BIPM, with the CIPM handling technical matters. It defines base units—the second, metre, kilogram, ampere, kelvin, mole, and candela—and derived units. In 2019, several base units were redefined in terms of fundamental constants: the second by cesium-133, the metre by the speed of light, the kilogram by the Planck constant, the ampere by the elementary charge, the kelvin by the Boltzmann constant, and the mole by the Avogadro constant.

National metrology institutes coordinate national standards, provide calibration and measurement services, maintain reference materials, and participate in international comparisons to assure consistency. Measurements rely on metrological traceability, the unbroken chain of calibrations linking results to SI units, with associated uncertainty estimates.

Legal metrology governs measurement-related regulation in commerce, health, and safety, setting requirements for devices such as scales, fuel dispensers, gas meters, and taximeters. Metrology underpins a wide range of sectors, including manufacturing, pharmaceuticals, healthcare, environmental monitoring, and energy management, ensuring reliability, quality, and compliance.