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Metrology

What is metrology?

Metrology is the science of measurement and its application. NIST's work in metrology focuses on advancing measurement science to enhance economic security and improve quality of life. 

What is NIST's role?

Almost all of NIST’s research has a metrology component to it. NIST’s metrology-related resources and activities include  calibrations, standard reference materials, standard reference data, test methods, proficiency evaluation materials, tools that facilitate the evaluation of measurement uncertainty, measurement quality assurance programs, and laboratory accreditation services that assist customers in establishing traceability of measurement results.

A key component of NIST’s metrology work is metrological traceability, which requires the establishment of an unbroken chain of calibrations to specified reference measurement standards: typically national or international standards, in particular realizations of the measurement units of the International System of Units (SI). 

NIST assures the traceability to the SI, or to other specified standards, of measurement results that NIST itself provides, either directly or through an official NIST program or collaboration. Other organizations are responsible for establishing the traceability of their own results to national reference standards maintained by NIST or to other specified reference standards. Learn more about metrological traceability.

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