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<p>NIST supports accurate and compatible measurements by certifying and providing over 1300 Standard Reference Materials® with well-characterized composition or properties, or both. These materials are used to perform instrument calibrations in units as part of overall quality assurance programs, to verify the accuracy of specific measurements and to support the development of new measurement methods.</p><p>Industry, academia, and government use NIST SRMs to facilitate commerce and trade and to advance research and development. Presently NIST SRMs are currently available for use in areas such as industrial materials production and analysis, environmental analysis, health measurements and basic measurements in science and metrology. NIST SRMs are also one mechanism for supporting measurement traceability in the United States.</p><p>Each NIST Standard Reference Material® is supplied with a Certificate of Analysis and a Materials Safety Data Sheet, when applicable. In addition, NIST has published many articles and practice guides that describe the development, analysis and use of SRMs.</p><p>The SRM Program references a number of definitions in connection with the production, certification, and use of its SRMs and RMs. Certain definitions, adopted for SRM use, are derived from international guides and standards on reference materials and measurements while others have been developed by the SRM Program to describe those activities unique to NIST operations.</p><p>An NTRM (NIST Traceable Reference Material) is a commercially produced reference material with a well-defined traceability linkage to existing NIST standards. This traceability linkage is established via criteria and protocols defined by NIST. Commercial reference materials producers may affix the NTRM trademark to materials produced according to these criteria and protocols.</p><p>Links to the laboratories at NIST that produce SRMs:</p><ul><li><a href="https://www.nist.gov/el" id="http://www.nist.gov/el|">Engineering Laboratory (EL)</a></li><li><a href="https://www.nist.gov/mml" id="http://www.nist.gov/mml|">Material Measurement Laboratory (MML)</a></li><li><a href="https://www.nist.gov/pml" id="http://www.nist.gov/pml|">Physical Measurement Laboratory (PML)</a></li></ul>
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