{"id":19677,"date":"2025-05-21T17:23:57","date_gmt":"2025-05-21T15:23:57","guid":{"rendered":"https:\/\/www.acrn.fr\/metrology-vocabulary-explained-simply\/"},"modified":"2026-04-16T15:48:14","modified_gmt":"2026-04-16T13:48:14","slug":"metrology-vocabulary-explained-simply","status":"publish","type":"post","link":"https:\/\/www.acrn.fr\/en\/metrology-vocabulary-explained-simply\/","title":{"rendered":"Metrology vocabulary explained simply: key terms"},"content":{"rendered":"\n<p class=\"has-black-color has-text-color has-link-color wp-elements-7707f1d07eb731744451629a09b00031 wp-block-paragraph\">In the industrial world, metrology plays an essential role. <\/p>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-bcf3c80ed3a79539f14e28febe551f7a wp-block-paragraph\">It guarantees measurement reliability, product conformity and process performance. Yet its technical vocabulary may seem complex at first glance. <\/p>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-5b299304d847b2995278457354bb9014 wp-block-paragraph\">This article offers a clear and accessible explanation of the main terms used in metrology, to help you better understand this precise and indispensable field.<\/p>\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n<h2 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-da9135513ca754f2eeb66e6dd8d70dbf\">What is metrology?<\/h2>\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-b53d5307bc8c2fa4e24af48efff7418a\">General definition of metrology<\/h3>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-2fcbf7d0d369fc1b0c4dc6f44addac57 wp-block-paragraph\">Metrology is the science of measurement. It covers all methods, resources and practices designed to guarantee the accuracy and reliability of measurements in all fields: industry, health, research, etc.<\/p>\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-be55382cd2b3c9c4aefeb83a031caac2\">Why is metrology important in industry?<\/h3>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-3b998af8c2095771ede0a3e69efbb6b3 wp-block-paragraph\">Metrology ensures : <\/p>\n\n<ul class=\"wp-block-list\">\n<li class=\"has-black-color has-text-color has-link-color wp-elements-7445ac620c72a32eee05914579da7ba5\">Product compliance with standards.<\/li>\n\n\n\n<li class=\"has-black-color has-text-color has-link-color wp-elements-eb1ac2067769fc591ec221dfdb17a05f\">Safety and quality in industrial processes.<\/li>\n\n\n\n<li class=\"has-black-color has-text-color has-link-color wp-elements-663c45aff3e87e3ca8973b5cd71ae2b0\">International comparability of measurements<\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\">\ud83d\udc49 <a href=\"https:\/\/www.acrn.fr\/en\/our-product-lines\/\"><em>Discover our metrology solutions for industry<\/em><\/a><\/p>\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n<h2 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-71cb891c3adf8b48325d7f93f27aadd4\">The main metrology families<\/h2>\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-2f68212221c4eed3d2771845bf3b18ec\">Scientific metrology<\/h3>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-714683c3125a16ee9b0d5b602846b569 wp-block-paragraph\">It focuses on the fundamental units (meter, kilogram, second, etc.) and their definition through universal constants. It is supported by national and international bodies such as the BIPM (Bureau International des Poids et Mesures).<\/p>\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-f865ca74f60205da431ac3c82d53c171\">Industrial Metrology<\/h3>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-94a18526a40821528d78976740d62a0d wp-block-paragraph\">It&#8217;s the one that most concerns us in the production sector. It ensures that the measuring equipment used in the company complies with an adequate level of precision.<\/p>\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-35e38cf22a1966bacdcddf8167114120\">Legal metrology<\/h3>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-e812edaf61a5ef74fa9df547b1141bae wp-block-paragraph\">It concerns measuring instruments used in commercial transactions or for regulatory purposes (commercial scales, road radars, water meters, etc.).<\/p>\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n<h2 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-716c50fefab46f9225d32641051eda41\">Metrology terms<\/h2>\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-c9978a985f28222b190f554bdaa2c254\">Measuring instrument<\/h3>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-5472889c6d059b36ee13e236663ab85c wp-block-paragraph\">A measuring instrument is any device used to measure a physical quantity (length, weight, temperature, torque, etc.).<\/p>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-4f7dee24778341348a67b9617deadf4a wp-block-paragraph\">Example: micrometer, balance, torquemeter (torque measurement tool).<\/p>\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-f3685f097a1de15fd93720d38ea17a70\">Mesurande<\/h3>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-b649a5ee42b25174a80f3c08d4d66a11 wp-block-paragraph\">The measurand is the physical quantity to be measured. Example: the temperature of a liquid, the torque of a screw, the length of a part, etc.<\/p>\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-8ff84e116b4d079a505c6848062a7c6d\">R\u00e9solution<\/h3>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-dc3af1f2dad77716ab19ed67b306892c wp-block-paragraph\">Resolution refers to the smallest variation in magnitude that the instrument can detect. The finer it is, the more precise the measurement.<\/p>\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n<h2 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-469b7431d5940d38b1b3acf9101192bb\">Precision, accuracy and fidelity: what are the differences?<\/h2>\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-f123f879b3a7c35f5c697e020acd4b95\">Precision<\/h3>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-716b7718cb498c5f1a71ae7dbac010b4 wp-block-paragraph\">Precision reflects the dispersion of results obtained from repeated measurements. A precise instrument gives results that are very close to each other.<\/p>\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-ad73d2f61022ec97db32e1b6b8f0ad98\">Trueness<\/h3>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-e1a7ec01363a178d5bf0cbd97207b632 wp-block-paragraph\">Trueness measures the difference between the measured value and the actual value. A fair instrument gives a value close to reality.<\/p>\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-41235d13e65b82a855638fa62153d21a\">Repeatability<\/h3>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-e2f38feec5f2a6a9cb7afe78c894c7ab wp-block-paragraph\">Repeatability is the ability of an instrument to consistently reproduce measurements when conditions remain the same.<\/p>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-d3c8ef27d0c0d907d13d241ee372bc79 wp-block-paragraph\">\ud83d\udd0d Remember: a device can be precise but not accurate, or accurate but not faithful. The ideal is to combine all three!<\/p>\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n<h2 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-884c001a33a9e3722f3093efc39c6de6\">Measurement uncertainty<\/h2>\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-d6e820a448263d47b436380cf8989cd8\">Definition<\/h3>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-a4094bf8b8fd013946ce32986a707dd5 wp-block-paragraph\">Measurement uncertainty expresses the possible margin of error around the measured result. It is essential for the correct interpretation of a measurement.<\/p>\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-ac36fcc597cfea85b9785a8e6a387022\">Types of uncertainty<\/h3>\n\n<ul class=\"wp-block-list\">\n<li class=\"has-black-color has-text-color has-link-color wp-elements-11a8d932c8708650a3b2190314b20f89\">Type A uncertainty: estimated by statistical methods.<\/li>\n\n\n\n<li class=\"has-black-color has-text-color has-link-color wp-elements-e5724406bce107a00e99aa526c8013bf\">Type B uncertainty: estimated from experience, instrument specifications, etc.<\/li>\n<\/ul>\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n<h2 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-6369d45fced3db51b065cc4124be3235\"><strong>Calibration and verification: two complementary concepts<\/strong><\/h2>\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-a828a640ba49a431d379d10c0f6c61ae\"><strong>Calibration<\/strong><\/h3>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-c8c95b74ab457de73f5af0b29ee8ef18 wp-block-paragraph\"><strong>Calibration <\/strong> involves comparing a measuring instrument with a known, traceable reference, in order to determine any errors. It does not lead to acceptance or rejection. It is an essential part of any quality assurance plan.<\/p>\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-8690d78ad726476db59ddac0a1d2f321\"><strong>Verification<\/strong><\/h3>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-e7918ad1d185c23d6e5e5d8f35b96ff5 wp-block-paragraph\"><strong>Verification <\/strong> is the process of ensuring that an instrument meets defined requirements. The result is a decision on whether or not the device conforms.<\/p>\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n<h2 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-869108a59ccfdd27db11b50e66a97da3\"><strong>Metrological traceability<\/strong><\/h2>\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-fee412d81c1ff50399d41874a714d9e5\"><strong>What is traceability?<\/strong><\/h3>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-13eea2d532ab50946af1cc1a8b50e315 wp-block-paragraph\"><strong>Metrological traceability<\/strong> guarantees that a measurement can be linked to a national or international reference, via an unbroken chain of calibrations, each with its own uncertainty.<\/p>\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-af14fad2695fd0af07e679acd69b8ee1\"><strong>Why is this crucial?<\/strong><\/h3>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-bc417e6d9355955f0638be77c950689d wp-block-paragraph\">It enables :<\/p>\n\n<ul class=\"wp-block-list\">\n<li class=\"has-black-color has-text-color has-link-color wp-elements-41a96082b22be444b187c41125f9406e\">Worldwide comparability of results.<\/li>\n\n\n\n<li class=\"has-black-color has-text-color has-link-color wp-elements-79c6653a7d2440d3d31b74836bc1f1ff\">Compliance with iso standards (such as ISO 9001 or ISO\/IEC 17025)<\/li>\n\n\n\n<li class=\"has-black-color has-text-color has-link-color wp-elements-f27065f1f2ae0fd5619f059be1d11ca7\">Credibility of results in audits and certifications.<\/li>\n<\/ul>\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n<h2 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-9841ba8b42bec51c634779499fa9dde0\"><strong>Reference bodies in metrology<\/strong><\/h2>\n\n<ul class=\"wp-block-list\">\n<li class=\"has-black-color has-text-color has-link-color wp-elements-e5bd9936cc45e2688ebe57170d3aa105\"><strong>The BIPM (International Bureau of Weights and Measures)<\/strong> is responsible for defining and maintaining the International System of Units (SI).<\/li>\n\n\n\n<li class=\"has-black-color has-text-color has-link-color wp-elements-4ade3f79ef11121d03d449db1137586a\"><strong>COFRAC (French Accreditation Committee)<\/strong> : accredits calibration laboratories in France.<\/li>\n\n\n\n<li class=\"has-black-color has-text-color has-link-color wp-elements-8f7f7d1b6969fde375337ff3312d34f4\"><strong>LNE (National Laboratory for Metrology and Testing)<\/strong>: the national reference in measurement.<\/li>\n<\/ul>\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n<h2 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-591cf4ce2df2afa926db797b65d5a725\"><strong>Case study: metrology vocabulary applied to control equipment <\/strong>ACRN<\/h2>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-b216553ffa20c120f384b5e18cafe623 wp-block-paragraph\">Let&#8217;s take the example of a <strong>motorized torquemeter<\/strong> used to check the torque applied to a bottle in the food industry :<\/p>\n\n<ul class=\"wp-block-list\">\n<li class=\"has-black-color has-text-color has-link-color wp-elements-cc3ba9d625e82d6068df11b504d8fb1c\"><strong>Measurand<\/strong>: tightening torque in N-m.<\/li>\n\n\n\n<li class=\"has-black-color has-text-color has-link-color wp-elements-cb9f3ad6f5071298c3c9644e4cdec203\"><strong>Measuring instrument<\/strong>: torquemeter.<\/li>\n\n\n\n<li class=\"has-black-color has-text-color has-link-color wp-elements-1f7a460a2089a317a1ea1398263c0326\"><strong>Accuracy<\/strong>: difference between the measurement obtained and the set value.<\/li>\n\n\n\n<li class=\"has-black-color has-text-color has-link-color wp-elements-bcf864e790a8a27f120b70408d9194fe\"><strong>Calibration<\/strong>: carried out regularly with a certified reference.<\/li>\n\n\n\n<li class=\"has-black-color has-text-color has-link-color wp-elements-a1ab6347fd82d4d43fc3ed401529eff7\"><strong>Traceability<\/strong>: ensured by a chain of calibration to a national standard.<\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\"> Find out more about our <a href=\"https:\/\/www.acrn.fr\/en\/torque-measurement\/\"><em>torque measurement solutions<\/em><\/a><em>.<\/em><\/p>\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-link-color wp-elements-9052207b7d2cb94a08f1bcd3f918cc79\">Conclusion<\/h3>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-cfb85adbef68e694575babb9f4ae1f2a wp-block-paragraph\">Understanding the vocabulary of <strong>metrology <\/strong> is essential for any company concerned with quality and precision. Concepts such as measurement uncertainty, calibration and traceability are more than just technical terms: they guarantee process reliability and customer satisfaction.<\/p>\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-d8d6684b068109e7d0b92e4b9d45d622 wp-block-paragraph\">By making these concepts accessible, you&#8217;ll gain in autonomy in your quality procedures and in the efficiency of your controls.<\/p>\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>In the industrial world, metrology plays an essential role. It guarantees measurement reliability, product conformity and process performance. Yet its technical vocabulary may seem complex at first glance. This article offers a clear and accessible explanation of the main terms used in metrology, to help you better understand this precise and indispensable field. What is [&hellip;]<\/p>\n","protected":false},"author":3,"featured_media":19673,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"categories":[332],"tags":[],"dipi_cpt_category":[],"class_list":["post-19677","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-our-news"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.acrn.fr\/en\/wp-json\/wp\/v2\/posts\/19677","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.acrn.fr\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.acrn.fr\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.acrn.fr\/en\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.acrn.fr\/en\/wp-json\/wp\/v2\/comments?post=19677"}],"version-history":[{"count":1,"href":"https:\/\/www.acrn.fr\/en\/wp-json\/wp\/v2\/posts\/19677\/revisions"}],"predecessor-version":[{"id":23930,"href":"https:\/\/www.acrn.fr\/en\/wp-json\/wp\/v2\/posts\/19677\/revisions\/23930"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.acrn.fr\/en\/wp-json\/wp\/v2\/media\/19673"}],"wp:attachment":[{"href":"https:\/\/www.acrn.fr\/en\/wp-json\/wp\/v2\/media?parent=19677"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.acrn.fr\/en\/wp-json\/wp\/v2\/categories?post=19677"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.acrn.fr\/en\/wp-json\/wp\/v2\/tags?post=19677"},{"taxonomy":"dipi_cpt_category","embeddable":true,"href":"https:\/\/www.acrn.fr\/en\/wp-json\/wp\/v2\/dipi_cpt_category?post=19677"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}