Metrology | NIST

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<div class="nist-block nist-block--no-margin"> <div class="entity-reference"> <img loading="lazy" src="/web/20230927061217im_/https://www.nist.gov/sites/default/files/images/2021/02/18/Metrology_1200x248.png" width="1200" height="248" alt="Black background. Green lighting. Kilograms under glass domes." typeof="foaf:Image"/> </div> </div> </div> <div class="nist-section-header__main grid-container"> <div class="grid-row"> <div class="nist-section-header__title"> <h1 class="nist-page__title">Metrology</h1> </div> </div> </div> </div> </div> <div class="grid-container"> <div class="nist-page__region nist-page__region--topic-description padding-top-4 margin-top-1"> <div class="nist-region-heading"> <h2>Overview</h2> </div> <div class="grid-row"> <div class="tablet:grid-col-8 padding-right-5 margin-bottom-4"> <div class="text-with-summary"> <p>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. </p> <p>Almost all of NIST’s research has a metrology component to it. NIST’s metrology-related resources and activities include <a data-entity-substitution="canonical" data-entity-type="node" data-entity-uuid="d731b841-8e78-4fd4-9e23-8c9a41e30b3b" href="/web/20230927061217/https://www.nist.gov/calibrations" title="Calibrations">calibrations</a>, <a href="https://web.archive.org/web/20230927061217/https://www.nist.gov/srms">standard reference materials</a>, <a href="https://web.archive.org/web/20230927061217/https://www.nist.gov/srd">standard reference data</a>, test methods, proficiency evaluation materials, tools that facilitate the evaluation of measurement uncertainty, measurement quality assurance programs, and <a data-entity-substitution="canonical" data-entity-type="node" data-entity-uuid="e1e059d6-c5af-443d-974c-faa6ec719b6e" href="/web/20230927061217/https://www.nist.gov/nvlap" title="National Voluntary Laboratory Accreditation Program (NVLAP)">laboratory accreditation services</a> that assist customers in establishing traceability of measurement results.</p> <p>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). </p> <p>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 <a data-entity-substitution="canonical" data-entity-type="node" data-entity-uuid="4adf979c-d4ae-47fe-9d9e-38d646f2d212" href="/web/20230927061217/https://www.nist.gov/publications/metrological-traceability-frequently-asked-questions-and-nist-policy" title="Metrological Traceability Frequently Asked Questions and NIST Policy">metrological traceability</a>.</p> </div> </div> <div class="tablet:grid-col-4"> <div class="nist-block nist-block--no-margin"> <h2 class="nist-block__title">Featured Content</h2> <div class="nist-field nist-field--label-hidden nist-field--link-list link font-sans-sm"> <div class="nist-field__items"> <div class="nist-field__item"><a href="/web/20230927061217/https://www.nist.gov/si-redefinition">SI Redefinition</a></div> <div class="nist-field__item"><a href="/web/20230927061217/https://www.nist.gov/metrology/metrological-traceability">Metrological Traceability: Frequently Asked Questions and NIST Policy</a></div> <div class="nist-field__item"><a href="/web/20230927061217/https://www.nist.gov/nist-quality-system">NIST Quality System</a></div> <div class="nist-field__item"><a href="https://web.archive.org/web/20230927061217/https://uncertainty.nist.gov/">NIST Uncertainty Machine</a></div> </div> </div> </div> </div> </div> </div> </div> <div class="bg-base-lightest padding-y-5 margin-y-4"> <div class="nist-page__region nist-page__region--topic-list grid-container"> <div class="views-element-container nist-block margin-bottom-0"> <div><div class="js-view-dom-id-ad487a32df7b6f870ce445069e2a1ec766b01a95171ccafe4a66e8638754c358"> <div class="nist-block margin-bottom-0"> <div class="nist-region-heading"> <h2>Metrology Topics</h2> </div> <ul class="add-list-reset link-list"> <div class="grid-row"> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20230927061217/https://www.nist.gov/amount-substance" hreflang="en">Amount of substance</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20230927061217/https://www.nist.gov/dimensional-metrology" hreflang="en">Dimensional metrology</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20230927061217/https://www.nist.gov/electrical-electromagnetic-metrology" hreflang="en">Electrical / electromagnetic metrology</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20230927061217/https://www.nist.gov/flow-metrology-rheology" hreflang="en">Flow metrology & rheology</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20230927061217/https://www.nist.gov/force-metrology" hreflang="en">Force metrology</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20230927061217/https://www.nist.gov/humidity-metrology" hreflang="en">Humidity metrology</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20230927061217/https://www.nist.gov/ionizing-radiation-metrology" hreflang="en">Ionizing radiation metrology</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20230927061217/https://www.nist.gov/mass-metrology" hreflang="en">Mass metrology</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20230927061217/https://www.nist.gov/metric" hreflang="en">Metric</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20230927061217/https://www.nist.gov/optical-photometry-laser-metrology" hreflang="en">Optical / photometry / laser metrology</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20230927061217/https://www.nist.gov/pressure-vacuum-metrology" hreflang="en">Pressure & vacuum metrology</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20230927061217/https://www.nist.gov/thermometry-metrology" hreflang="en">Thermometry metrology</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20230927061217/https://www.nist.gov/time-frequency-metrology" hreflang="en">Time & frequency metrology</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20230927061217/https://www.nist.gov/weights-measures" hreflang="en">Weights & measures</a></div></div></li> </div> </div> </ul> </div> </div> </div> </div> </div> </div> <div class="nist-page__region nist-page__region--main"> <div class="nist-block"> <div class="grid-container margin-y-5"> <div class="paragraph paragraph--type--topic-research paragraph--view-mode--default"> <div class="nist-region-heading"> <h2>The Research</h2> </div> <div class="grid-row"> <div class="tablet:grid-col-8 padding-right-5 margin-y-2"> <h2 class="nist-block__title">Projects & Programs</h2> <article role="article" about="/programs-projects/precision-electro-mechanical-experiments-preme" class="nist-teaser"> <div class="nist-teaser__image"> <div class="entity-reference"> <a href="/web/20230927061217/https://www.nist.gov/programs-projects/precision-electro-mechanical-experiments-preme" hreflang="en"><img loading="lazy" src="/web/20230927061217im_/https://www.nist.gov/sites/default/files/styles/thumbnail/public/images/2021/04/30/nist-4.jpg?itok=XwzL7MbX" width="66" height="100" alt="NIST-4" typeof="foaf:Image"/> </a> </div> </div> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/web/20230927061217/https://www.nist.gov/programs-projects/precision-electro-mechanical-experiments-preme"><span>Precision Electro-Mechanical Experiments (PREME)</span> </a></h3> <div class="nist-teaser__type"> <div class="nist-badge display-inline-block margin-y-1 nist-badge--blue boolean">Ongoing</div> </div> </header> <div class="nist-teaser__content"> <div class="text-long"> The Precision Electro-Mechanical Experiments (PREME) program develops precision electro-mechanical measurements for fundamental traceability of the SI units and </div> </div> </div> </article> <article role="article" about="/programs-projects/quantum-transport-measurements" class="nist-teaser"> <div class="nist-teaser__image"> <div class="entity-reference"> <a href="/web/20230927061217/https://www.nist.gov/programs-projects/quantum-transport-measurements" hreflang="en"><img loading="lazy" src="/web/20230927061217im_/https://www.nist.gov/sites/default/files/styles/thumbnail/public/images/2020/02/20/cr1.png?itok=JKP9ip_5" width="100" height="47" alt="Measuring interactions between chiral edge states. 2D heterostructure (left); magnetoresistance data (right)." typeof="foaf:Image"/> </a> </div> </div> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/web/20230927061217/https://www.nist.gov/programs-projects/quantum-transport-measurements"><span>Quantum Transport Measurements</span> </a></h3> <div class="nist-teaser__type"> <div class="nist-badge display-inline-block margin-y-1 nist-badge--blue boolean">Ongoing</div> </div> </header> <div class="nist-teaser__content"> <div class="text-long"> We are developing the foundational knowledge and measurement infrastructure that will facilitate the use of solid state systems with emergent quantum properties </div> </div> </div> </article> <article role="article" about="/programs-projects/acoustic-techniques-fluid-metrology" class="nist-teaser"> <div class="nist-teaser__image"> <div class="entity-reference"> <a href="/web/20230927061217/https://www.nist.gov/programs-projects/acoustic-techniques-fluid-metrology" hreflang="en"><img loading="lazy" src="/web/20230927061217im_/https://www.nist.gov/sites/default/files/styles/thumbnail/public/images/2016/12/14/acoustic_thermometer_a.jpg?itok=2PQeXWqx" width="90" height="100" alt="The NIST Acoustic Thermometer" typeof="foaf:Image"/> </a> </div> </div> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/web/20230927061217/https://www.nist.gov/programs-projects/acoustic-techniques-fluid-metrology"><span>Acoustic Techniques in Fluid Metrology</span> </a></h3> <div class="nist-teaser__type"> <div class="nist-badge display-inline-block margin-y-1 nist-badge--blue boolean">Ongoing</div> </div> </header> <div class="nist-teaser__content"> <div class="text-long"> The Fluid Metrology Group leads the world in designing and using gas-filled acoustic resonators for measuring the thermodynamic temperature T , the Boltzmann </div> </div> </div> </article> <article role="article" about="/programs-projects/chemical-metrology-polymers-manufacturing" class="nist-teaser"> <div class="nist-teaser__image"> <div class="entity-reference"> <a href="/web/20230927061217/https://www.nist.gov/programs-projects/chemical-metrology-polymers-manufacturing" hreflang="en"><img loading="lazy" src="/web/20230927061217im_/https://www.nist.gov/sites/default/files/styles/thumbnail/public/images/mml/csd/dscn0651_1.jpg?itok=x_BsTY-b" width="100" height="75" typeof="foaf:Image"/> </a> </div> </div> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/web/20230927061217/https://www.nist.gov/programs-projects/chemical-metrology-polymers-manufacturing"><span>Chemical Metrology for Polymers Manufacturing</span> </a></h3> <div class="nist-teaser__type"> <div class="nist-badge display-inline-block margin-y-1 nist-badge--blue boolean">Ongoing</div> </div> </header> <div class="nist-teaser__content"> <div class="text-long"> Chemical metrology for polymers manufacturing is a new area of endeavor for the Chemical Sciences Division. At the outset, efforts have involved mostly </div> </div> </div> </article> <div class="link-list"><a href="/web/20230927061217/https://www.nist.gov/laboratories/projects-programs/topic/249051">View All Projects/Programs</a></div> </div> <div class="tablet:grid-col-4 margin-y-2"> <h2 class="nist-block__title">Additional Resources Links</h2> <div class="nist-field nist-field--label-hidden nist-field--link-list link nist-field--link-list font-sans-sm"> <div class="nist-field__items"> <div class="nist-field__item"><a href="/web/20230927061217/https://www.nist.gov/publications/search?k=&d%5Bmin%5D=&d%5Bmax%5D=&t=&a=&s=All&ta%5B0%5D=249051&ta%5B1%5D=249051&n=">Publications</a></div> <div class="nist-field__item"><a href="/web/20230927061217/https://www.nist.gov/laboratories/tools-instruments/topic/249051">Tools & Instruments</a></div> </div> </div> </div> </div> </div> </div> <div class="paragraph paragraph--type--topic-featured paragraph--view-mode--default nist-content-row--width-full bg-base-lightest margin-y-5"> <div class="grid-container"> <div class="nist-card nist-card--horizontal nist-card--horizontal-full nist-card--base-lightest"> <div class="nist-card__inner"> <div class="nist-card__image"> <a href="/web/20230927061217/https://www.nist.gov/video/romance-precision-measurement"> <div class="entity-reference"> <figure class="nist-image"> <img src="/web/20230927061217im_/https://www.nist.gov/sites/default/files/styles/800w_x_400h/public/images/kaltura_import/2018/01/04/the_romance_of_precision_measurement_thumbnail.jpeg.webp?itok=tji6siMo" width="800" height="400" alt="The Romance of Precision Measurement Thumbnail" title="The Romance of Precision Measurement Thumbnail" loading="lazy" typeof="foaf:Image"/> <figcaption class="nist-image__caption"> <div data-caption-editable="true" class="nist-image__caption-content"> </div> </figcaption> </figure> </div> </a> </div> <div class="nist-card__title"> <h3> The Romance of Precision Measurement </h3> </div> <div class="nist-card__content"> <div class="text-long"><p>In 1953, then-NBS director Allen V. Astin spoke before the American Physical Society about NBS/NIST’s values, and the critical role scientific advances played in supporting U.S. industry. It’s a message that has resonated with NBS/NIST directors ever since.</p></div> </div> <div class="nist-card__links"> <div class="nist-card__button"> <a href="/web/20230927061217/https://www.nist.gov/video/romance-precision-measurement" class="usa-button ">View video</a> </div> </div> </div> </div> </div> </div> <div class="grid-container margin-y-4"> <div class="nist-region-heading"> <h2>News</h2> </div> <div class="margin-bottom-5"> <div class="entity-reference"> <div class="nist-card nist-card--horizontal nist-card--horizontal-full"> <div class="nist-card__inner"> <div class="nist-card__image"> <a href="/web/20230927061217/https://www.nist.gov/blogs/taking-measure/last-artifact-brings-metrology-tv"> <div class="entity-reference"> <img loading="lazy" src="/web/20230927061217im_/https://www.nist.gov/sites/default/files/styles/600w_x_360h/public/images/2020/08/20/Filming%20in%20the%20Kibble%20balance%20lab.jpg.webp?itok=c1xuNt9k" width="600" height="360" alt="Film crew films a pair NIST researchers operating the NIST Kibble balance" typeof="foaf:Image"/> </div> </a> </div> <div class="nist-card__title"> <h3><span>‘The Last Artifact’ Brings Metrology to TV</span> </h3> </div> <div class="nist-card__content"> <div class="text-with-summary"> Remember that documentary you saw that finally explained metrology and why measurements are critical to practically every aspect of modern life? Yeah, neither do I. Probably because that documentary doesn’t exist … Or does it? The Last Artifact , a new one-hour film that PBS stations are planning to broadcast starting this month , aims to fill that cinematic void by bringing metrology to the </div> </div> <div class="nist-card__links"> <div class="nist-card__button"> <a href="/web/20230927061217/https://www.nist.gov/blogs/taking-measure/last-artifact-brings-metrology-tv" class="usa-button ">Read more</a> </div> </div> </div> </div> </div> </div> <div class="paragraph paragraph--type--dynamic-news-list-topic paragraph--view-mode--default"> <div class="views-element-container"><div class="js-view-dom-id-b926c675539360ffeddc099572262bcf256993b4125d37c246cc31ec615bac32"> <div class="grid-row grid-gap-2"> <div class="nist-card tablet:grid-col-4 nist-card--topic "> <div class="nist-card__inner"> <div class="nist-card__image"> <a href="/web/20230927061217/https://www.nist.gov/news-events/news/2023/09/working-their-thermal-magic-digging-details-ambitious-new-thermometry"> <div class="entity-reference"> <img loading="lazy" src="/web/20230927061217im_/https://www.nist.gov/sites/default/files/styles/800w_x_400h/public/images/2023/09/25/DSC_1801.png.webp?itok=EtB93COI" width="800" height="400" alt="Thinh Bui with the Thermal MagIC system" typeof="foaf:Image"/> </div> </a> </div> <div class="nist-card__title padding-y-5"> <h3><span property="schema:name">Working Their Thermal MagIC: Digging Into the Details of an Ambitious New ’Thermometry Camera’</span> </h3> </div> <div class="nist-card__links"> <div class="nist-card__button"> <a href="/web/20230927061217/https://www.nist.gov/news-events/news/2023/09/working-their-thermal-magic-digging-details-ambitious-new-thermometry" class="usa-button ">Read more</a> </div> </div> </div> </div> <div class="nist-card tablet:grid-col-4 nist-card--topic "> <div class="nist-card__inner"> <div class="nist-card__image"> <a href="/web/20230927061217/https://www.nist.gov/news-events/news/2023/09/metric-week-2023-seven-days-si-fun"> <div class="entity-reference"> <img loading="lazy" src="/web/20230927061217im_/https://www.nist.gov/sites/default/files/styles/800w_x_400h/public/images/2023/09/19/2023-Metric%20Week_0.png.webp?itok=PzBSgbeP" width="800" height="400" alt="Graphic with dates of 2023 Metric Week" typeof="foaf:Image"/> </div> </a> </div> <div class="nist-card__title padding-y-5"> <h3><span property="schema:name">Metric Week 2023: Seven Days of SI Fun</span> </h3> </div> <div class="nist-card__links"> <div class="nist-card__button"> <a href="/web/20230927061217/https://www.nist.gov/news-events/news/2023/09/metric-week-2023-seven-days-si-fun" class="usa-button ">Read more</a> </div> </div> </div> </div> <div class="nist-card tablet:grid-col-4 nist-card--topic "> <div class="nist-card__inner"> <div class="nist-card__image"> <a href="/web/20230927061217/https://www.nist.gov/news-events/news/2023/09/unity-photon-community"> <div class="entity-reference"> <img loading="lazy" src="/web/20230927061217im_/https://www.nist.gov/sites/default/files/styles/800w_x_400h/public/images/pml/div686/14pml031_triplets_lr.jpg.webp?itok=j5AG1IRF" width="800" height="400" alt="NIST chip containing a single-photon detector made of superconducting nanowires. 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