As the U.S. NMI for hardness, NIST's role is to improve hardness measurement at all levels of traceability. The hardness traceability structure begins with the Consultative Committee for Mass and Related Quantities (CCM) Working Group on Hardness (WGH) under the umbrella of the International Committee for Weights and Measures (CIPM). NIST represents the U.S. in this committee by providing input in the development of the hardness definitions. NIST participates in worldwide comparisons between NMIs, and interacts bilaterally with the standardizing laboratories of other countries.
NIST transfers the U.S. national hardness scales to industry by way of SRMs sold primarily to secondary calibration laboratories, and takes additional steps to ensure that the hardness SRMs are used effectively, through participation in laboratory accreditations.
Almost all industrial hardness measurements, whether made at calibration laboratories or industrial facilities, follow the test method procedures developed by Standard Development Organizations (SDOs) such as ASTM-International and the International Organization for Standardization (ISO). Through our participation and leadership in these hardness committees, NIST is able to communicate its expertise, research, and experience.