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Standard temperature and pressure

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A technical standard is an established norm or requirement for a repeatable technical task which is applied to a common and repeated use of rules, conditions, guidelines or characteristics for products or related processes and production methods, and related management systems practices. A technical standard includes definition of terms; classification of components; delineation of procedures; specification of dimensions, materials, performance, designs, or operations; measurement of quality and quantity in describing materials, processes, products, systems, services, or practices; test methods and sampling procedures; or descriptions of fit and measurements of size or strength.

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69-623: Standard temperature and pressure ( STP ) or standard conditions for temperature and pressure are various standard sets of conditions for experimental measurements used to allow comparisons to be made between different sets of data. The most used standards are those of the International Union of Pure and Applied Chemistry (IUPAC) and the National Institute of Standards and Technology (NIST), although these are not universally accepted. Other organizations have established

138-417: A coordination problem : it emerges from situations in which all parties realize mutual gains, but only by making mutually consistent decisions. Examples : Private standards are developed by private entities such as companies, non-governmental organizations or private sector multi-stakeholder initiatives, also referred to as multistakeholder governance . Not all technical standards are created equal. In

207-526: A metrology agency, the Bureau of Standards was directed by Herbert Hoover to set up divisions to develop commercial standards for materials and products. Some of these standards were for products intended for government use, but product standards also affected private-sector consumption. Quality standards were developed for products including some types of clothing, automobile brake systems and headlamps, antifreeze , and electrical safety. During World War I ,

276-476: A neutron science user facility: the NIST Center for Neutron Research (NCNR). The NCNR provides scientists access to a variety of neutron scattering instruments, which they use in many research fields (materials science, fuel cells, biotechnology, etc.). The SURF III Synchrotron Ultraviolet Radiation Facility is a source of synchrotron radiation , in continuous operation since 1961. SURF III now serves as

345-582: A NIST team as part of a DARPA competition. In September 2013, both The Guardian and The New York Times reported that NIST allowed the National Security Agency (NSA) to insert a cryptographically secure pseudorandom number generator called Dual EC DRBG into NIST standard SP 800-90 that had a kleptographic backdoor that the NSA can use to covertly predict the future outputs of this pseudorandom number generator thereby allowing

414-694: A combination of vacuum tubes and solid-state diode logic. About the same time the Standards Western Automatic Computer , was built at the Los Angeles office of the NBS by Harry Huskey and used for research there. A mobile version, DYSEAC , was built for the Signal Corps in 1954. Due to a changing mission, the "National Bureau of Standards" became the "National Institute of Standards and Technology" in 1988. Following

483-509: A custom, convention, company product, corporate standard, and so forth that becomes generally accepted and dominant is often called a de facto standard. A technical standard may be developed privately or unilaterally, for example by a corporation, regulatory body, military, etc. Standards can also be developed by groups such as trade unions and trade associations. Standards organizations often have more diverse input and usually develop voluntary standards: these might become mandatory if adopted by

552-488: A draft of the CSF 2.0 for public comment through November 4, 2023. NIST decided to update the framework to make it more applicable to small and medium size enterprises that use the framework, as well as to accommodate the constantly changing nature of cybersecurity. In August 2024, NIST released a final set of encryption tools designed to withstand the attack of a quantum computer. These post-quantum encryption standards secure

621-434: A government (i.e., through legislation ), business contract, etc. The standardization process may be by edict or may involve the formal consensus of technical experts. The primary types of technical standards are: Technical standards are defined as: Technical standards may exist as: When a geographically defined community must solve a community-wide coordination problem , it can adopt an existing standard or produce

690-515: A large user base, doing some well established thing that between them is mutually incompatible. Establishing national/regional/international standards is one way of preventing or overcoming this problem. To further support this, the WTO Technical Barriers to Trade (TBT) Committee published the "Six Principles" guiding members in the development of international standards. The existence of a published standard does not imply that it

759-412: A new one. The main geographic levels are: National/Regional/International standards is one way of overcoming technical barriers in inter-local or inter-regional commerce caused by differences among technical regulations and standards developed independently and separately by each local, local standards organisation , or local company. Technical barriers arise when different groups come together, each with

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828-621: A number of papers in relation to the proliferation of private food safety standards in the agri-food industry, mostly driven by standard harmonization under the multistakeholder governance of the Global Food Safety Initiative (GFSI). With concerns around private standards and technical barriers to trade (TBT), and unable to adhere to the TBT Committee's Six Principles for the development of international standards because private standards are non-consensus,

897-539: A program to provide metrology services for United States scientific and commercial users. A laboratory site was constructed in Washington, DC , and instruments were acquired from the national physical laboratories of Europe. In addition to weights and measures, the Bureau developed instruments for electrical units and for measurement of light. In 1905 a meeting was called that would be the first "National Conference on Weights and Measures". Initially conceived as purely

966-562: A single international standard ; ISO 9001 (quality), ISO 14001 (environment), ISO 45001 (occupational health and safety), ISO 27001 (information security) and ISO 22301 (business continuity). Another example of a sector working with a single international standard is ISO 13485 (medical devices), which is adopted by the International Medical Device Regulators Forum (IMDRF). In 2020, Fairtrade International , and in 2021, Programme for

1035-429: A temperature of 15 °C (59 °F), pressure of 101,325 pascals (14.6959 psi) (1 atm ), and a density of 1.2250 kilograms per cubic meter (0.07647 lb/cu ft). It also specifies a temperature lapse rate of −6.5 °C (-11.7 °F) per km (approximately −2 °C (-3.6 °F) per 1,000 ft). The International Standard Atmosphere is representative of atmospheric conditions at mid latitudes. In

1104-424: A temperature of 20 °C (293.15 K, 68 °F) and an absolute pressure of 1 atm (14.696 psi, 101.325 kPa). This standard is also called normal temperature and pressure (abbreviated as NTP ). However, a common temperature and pressure in use by NIST for thermodynamic experiments is 298.15 K (25° C , 77° F ) and 1 bar (14.5038 psi , 100 kPa ). NIST also uses 15 °C (59 °F) for

1173-644: A user-accessible cleanroom nanomanufacturing facility. This "NanoFab" is equipped with tools for lithographic patterning and imaging (e.g., electron microscopes and atomic force microscopes ). NIST has seven standing committees: As part of its mission, NIST supplies industry, academia, government, and other users with over 1,300 Standard Reference Materials (SRMs). These artifacts are certified as having specific characteristics or component content, used as calibration standards for measuring equipment and procedures, quality control benchmarks for industrial processes, and experimental control samples. NIST publishes

1242-575: A variety of other definitions. In industry and commerce , the standard conditions for temperature and pressure are often necessary for expressing the volumes of gases and liquids and related quantities such as the rate of volumetric flow (the volumes of gases vary significantly with temperature and pressure): standard cubic meters per second (Sm/s), and normal cubic meters per second (Nm/s). Many technical publications (books, journals, advertisements for equipment and machinery) simply state "standard conditions" without specifying them; often substituting

1311-548: A wide range of electronic information, from confidential email messages to e-commerce transactions that propel the modern economy. Four scientific researchers at NIST have been awarded Nobel Prizes for work in physics : William Daniel Phillips in 1997, Eric Allin Cornell in 2001, John Lewis Hall in 2005 and David Jeffrey Wineland in 2012, which is the largest number for any US government laboratory not accounting for ubiquitous government contracts to state institutions and

1380-404: Is always useful or correct. For example, if an item complies with a certain standard, there is not necessarily assurance that it is fit for any particular use. The people who use the item or service (engineers, trade unions, etc.) or specify it (building codes, government, industry, etc.) have the responsibility to consider the available standards, specify the correct one, enforce compliance, and use

1449-479: Is an agency of the United States Department of Commerce whose mission is to promote American innovation and industrial competitiveness. NIST's activities are organized into physical science laboratory programs that include nanoscale science and technology , engineering , information technology , neutron research, material measurement, and physical measurement. From 1901 to 1988, the agency

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1518-457: Is as important to indicate the applicable reference conditions of temperature and pressure when stating the molar volume of a gas as it is when expressing a gas volume or volumetric flow rate. Stating the molar volume of a gas without indicating the reference conditions of temperature and pressure has very little meaning and can cause confusion. The molar volume of gases around STP and at atmospheric pressure can be calculated with an accuracy that

1587-649: Is now the Handbook 44 since 1918 and began publication under the current name in 1949. The 2010 edition conforms to the concept of the primary use of the SI (metric) measurements recommended by the Omnibus Foreign Trade and Competitiveness Act of 1988 . NIST is developing government-wide identity document standards for federal employees and contractors to prevent unauthorized persons from gaining access to government buildings and computer systems. In 2002,

1656-575: Is providing practical guidance and tools to better prepare facility owners, contractors, architects, engineers, emergency responders, and regulatory authorities to respond to future disasters. The investigation portion of the response plan was completed with the release of the final report on 7 World Trade Center on November 20, 2008. The final report on the WTC Towers—including 30 recommendations for improving building and occupant safety—was released on October 26, 2005. NIST works in conjunction with

1725-606: Is the molecular mass of the gas. The US Standard Atmosphere (USSA) uses 8.31432 m·Pa/(mol·K) as the value of R . However, the USSA in 1976 does recognize that this value is not consistent with the values of the Avogadro constant and the Boltzmann constant . Technical standard It is usually a formal document that establishes uniform engineering or technical criteria, methods, processes, and practices. In contrast,

1794-461: Is the mean atmospheric pressure at an altitude of about 112 metres, which is closer to the worldwide median altitude of human habitation (194 m). Natural gas companies in Europe, Australia, and South America have adopted 15 °C (59 °F) and 101.325 kPa (14.696 psi) as their standard gas volume reference conditions, used as the base values for defining the standard cubic meter . Also,

1863-406: Is usually sufficient by using the ideal gas law . The molar volume of any ideal gas may be calculated at various standard reference conditions as shown below: Technical literature can be confusing because many authors fail to explain whether they are using the ideal gas constant R , or the specific gas constant R s . The relationship between the two constants is R s = R / m , where m

1932-575: The Biden administration began plans to create a U.S. AI Safety Institute within NIST to coordinate AI safety matters. According to The Washington Post , NIST is considered "notoriously underfunded and understaffed", which could present an obstacle to these efforts. NIST, known between 1901 and 1988 as the National Bureau of Standards (NBS), is a measurement standards laboratory , also known as

2001-525: The Constitution of the United States , ratified in 1789, granted these powers to the new Congress: "The Congress shall have power ... To coin money, regulate the value thereof, and of foreign coin, and fix the standard of weights and measures". In January 1790, President George Washington , in his first annual message to Congress , said, "Uniformity in the currency, weights, and measures of

2070-752: The Handbook 44 each year after the annual meeting of the National Conference on Weights and Measures (NCWM). Each edition is developed through cooperation of the Committee on Specifications and Tolerances of the NCWM and the Weights and Measures Division (WMD) of NIST. The purpose of the book is a partial fulfillment of the statutory responsibility for "cooperation with the states in securing uniformity of weights and measures laws and methods of inspection". NIST has been publishing various forms of what

2139-710: The International Organization for Standardization (ISO), the United States Environmental Protection Agency (EPA) and National Institute of Standards and Technology (NIST) each have more than one definition of standard reference conditions in their various standards and regulations. Abbreviations: In aeronautics and fluid dynamics the " International Standard Atmosphere " (ISA) is a specification of pressure, temperature, density, and speed of sound at each altitude. At standard mean sea level it specifies

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2208-568: The National Construction Safety Team Act mandated NIST to conduct an investigation into the collapse of the World Trade Center buildings 1 and 2 and the 47-story 7 World Trade Center. The "World Trade Center Collapse Investigation", directed by lead investigator Shyam Sunder, covered three aspects, including a technical building and fire safety investigation to study the factors contributing to

2277-559: The National Medal of Science has been awarded to NIST researchers Cahn (1998) and Wineland (2007). Other notable people who have worked at NBS or NIST include: Since 1989, the director of NIST has been a Presidential appointee and is confirmed by the United States Senate , and since that year the average tenure of NIST directors has fallen from 11 years to 2 years in duration. Since the 2011 reorganization of NIST,

2346-737: The September 11, 2001 attacks, under the National Construction Safety Team Act (NCST), NIST conducted the official investigation into the collapse of the World Trade Center buildings. Following the 2021 Surfside condominium building collapse , NIST sent engineers to the site to investigate the cause of the collapse. In 2019, NIST launched a program named NIST on a Chip to decrease the size of instruments from lab machines to chip size. Applications include aircraft testing, communication with satellites for navigation purposes, and temperature and pressure. In 2023,

2415-870: The Technical Guidelines Development Committee of the Election Assistance Commission to develop the Voluntary Voting System Guidelines for voting machines and other election technology. In February 2014 NIST published the NIST Cybersecurity Framework that serves as voluntary guidance for organizations to manage and reduce cybersecurity risk. It was later amended and Version 1.1 was published in April 2018. Executive Order 13800, Strengthening

2484-842: The Treaty of the Meter , which established the International Bureau of Weights and Measures under the control of an international committee elected by the General Conference on Weights and Measures . NIST is headquartered in Gaithersburg, Maryland , and operates a facility in Boulder, Colorado , which was dedicated by President Eisenhower in 1954. NIST's activities are organized into laboratory programs and extramural programs. Effective October 1, 2010, NIST

2553-583: The WTO does not rule out the possibility that the actions of private standard-setting bodies may be subject to WTO law. BSI Group compared private food safety standards with "plugs and sockets", explaining the food sector is full of "confusion and complexity". Also, "the multiplicity of standards and assurance schemes has created a fragmented and inefficient supply chain structure imposing unnecessary costs on businesses that have no choice but to pass on to consumers". BSI provide examples of other sectors working with

2622-700: The proximity fuze and the standardized airframe used originally for Project Pigeon , and shortly afterwards the autonomously radar-guided Bat anti-ship guided bomb and the Kingfisher family of torpedo-carrying missiles. In 1948, financed by the United States Air Force, the Bureau began design and construction of SEAC , the Standards Eastern Automatic Computer. The computer went into operation in May 1950 using

2691-406: The Bureau worked on multiple problems related to war production, even operating its own facility to produce optical glass when European supplies were cut off. Between the wars, Harry Diamond of the Bureau developed a blind approach radio aircraft landing system. During World War II, military research and development was carried out, including development of radio propagation forecast methods,

2760-729: The Cybersecurity of Federal Networks and Critical Infrastructure , made the Framework mandatory for U.S. federal government agencies. An extension to the NIST Cybersecurity Framework is the Cybersecurity Maturity Model (CMMC) which was introduced in 2019 (though the origin of CMMC began with Executive Order 13556). It emphasizes the importance of implementing Zero-trust architecture (ZTA) which focuses on protecting resources over

2829-702: The EC-DRBG algorithm from the NIST SP 800-90 standard. In addition to these journals, NIST (and the National Bureau of Standards before it) has a robust technical reports publishing arm. NIST technical reports are published in several dozen series, which cover a wide range of topics, from computer technology to construction to aspects of standardization including weights, measures and reference data. In addition to technical reports, NIST scientists publish many journal and conference papers each year; an database of these, along with more recent technical reports, can be found on

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2898-468: The Endorsement of Forest Certification (PEFC) issued position statements defending their use of private standards in response to reports from The Institute for Multi-Stakeholder Initiative Integrity (MSI Integrity) and Greenpeace. Private standards typically require a financial contribution in terms of an annual fee from the organizations who adopt the standard. Corporations are encouraged to join

2967-536: The NIST cryptography process because of its recognized expertise. NIST is also required by statute to consult with the NSA." Recognizing the concerns expressed, the agency reopened the public comment period for the SP800-90 publications, promising that "if vulnerabilities are found in these or any other NIST standards, we will work with the cryptographic community to address them as quickly as possible". Due to public concern of this cryptovirology attack, NIST rescinded

3036-600: The National Metrological Institute (NMI), which is a non-regulatory agency of the United States Department of Commerce . The institute's official mission is to: Promote U.S. innovation and industrial competitiveness by advancing measurement science , standards , and technology in ways that enhance economic security and improve our quality of life . NIST had an operating budget for fiscal year 2007 (October 1, 2006 – September 30, 2007) of about $ 843.3 million. NIST's 2009 budget

3105-511: The US national standard for source-based radiometry throughout the generalized optical spectrum. All NASA -borne, extreme-ultraviolet observation instruments have been calibrated at SURF since the 1970s, and SURF is used for the measurement and characterization of systems for extreme ultraviolet lithography . The Center for Nanoscale Science and Technology (CNST) performs research in nanotechnology , both through internal research efforts and by running

3174-462: The US this information is specified the U.S. Standard Atmosphere which is identical to the "International Standard Atmosphere" at all altitudes up to 65,000 feet above sea level. Because many definitions of standard temperature and pressure differ in temperature significantly from standard laboratory temperatures (e.g. 0 °C vs. ~28 °C), reference is often made to "standard laboratory conditions" (a term deliberately chosen to be different from

3243-487: The United States is an object of great importance, and will, I am persuaded, be duly attended to." On October 25, 1791, Washington again appealed Congress: A uniformity of the weights and measures of the country is among the important objects submitted to you by the Constitution and if it can be derived from a standard at once invariable and universal, must be no less honorable to the public council than conducive to

3312-443: The board of governance of the standard owner which enables reciprocity. Meaning corporations have permission to exert influence over the requirements in the standard, and in return the same corporations promote the standards in their supply chains which generates revenue and profit for the standard owner. Financial incentives with private standards can result in a perverse incentive , where some private standards are created solely with

3381-522: The country. NIST publishes the Handbook 44 that provides the "Specifications, tolerances, and other technical requirements for weighing and measuring devices". The Congress of 1866 made use of the metric system in commerce a legally protected activity through the passage of Metric Act of 1866 . On May 20, 1875, 17 out of 20 countries signed a document known as the Metric Convention or

3450-461: The development of a technical standard, private standards adopt a non-consensus process in comparison to voluntary consensus standards. This is explained in the paper International standards and private standards . The International Trade Centre published a literature review series with technical papers on the impacts of private standards and the Food and Agriculture Organization (FAO) published

3519-493: The director also holds the title of Under Secretary of Commerce for Standards and Technology. Fifteen individuals have officially held the position (in addition to four acting directors who have served on a temporary basis). NIST holds patents on behalf of the Federal government of the United States , with at least one of them being custodial to protect public domain use, such as one for a Chip-scale atomic clock , developed by

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3588-509: The intent of generating money. BRCGS, as scheme owner of private standards, was acquired in 2016 by LGC Ltd who were owned by private equity company Kohlberg Kravis Roberts . This acquisition triggered substantial increases in BRCGS annual fees. In 2019, LGC Ltd was sold to private equity companies Cinven and Astorg. National Institute of Standards and Technology The National Institute of Standards and Technology ( NIST )

3657-411: The item correctly. Validation of suitability is necessary. Standards often get reviewed, revised and updated on a regular basis. It is critical that the most current version of a published standard be used or referenced. The originator or standard writing body often has the current versions listed on its web site. In social sciences , including economics , a standard is useful if it is a solution to

3726-463: The metric system of units defined the standard reference conditions of temperature and pressure for expressing gas volumes as being 15 °C (288.15 K; 59.00 °F) and 101.325  kPa (1.00  atm ; 760  Torr ). During those same years, the most commonly used standard reference conditions for people using the imperial or U.S. customary systems was 60 °F (15.56 °C; 288.71 K) and 14.696  psi (1 atm) because it

3795-409: The national physical laboratory for the United States. Southard had previously sponsored a bill for metric conversion of the United States. President Theodore Roosevelt appointed Samuel W. Stratton as the first director. The budget for the first year of operation was $ 40,000. The Bureau took custody of the copies of the kilogram and meter bars that were the standards for US measures, and set up

3864-429: The network perimeter. ZTA utilizes zero trust principles which include "never trust, always verify", "assume breach" and "least privileged access" to safeguard users, assets, and resources. Since ZTA holds no implicit trust to users within the network perimeter, authentication and authorization are performed at every stage of a digital transaction. This reduces the risk of unauthorized access to resources. NIST released

3933-547: The private sector. All four were recognized for their work related to laser cooling of atoms, which is directly related to the development and advancement of the atomic clock. In 2011, Dan Shechtman was awarded the Nobel Prize in chemistry for his work on quasicrystals in the Metallurgy Division from 1982 to 1984. In addition, John Werner Cahn was awarded the 2011 Kyoto Prize for Materials Science, and

4002-482: The probable cause of the collapses of the WTC Towers (WTC 1 and 2) and WTC 7. NIST also established a research and development program to provide the technical basis for improved building and fire codes, standards, and practices, and a dissemination and technical assistance program to engage leaders of the construction and building community in implementing proposed changes to practices, standards, and codes. NIST also

4071-481: The public convenience. In 1821, President John Quincy Adams declared, "Weights and measures may be ranked among the necessities of life to every individual of human society.". Nevertheless, it was not until 1838 that the United States government adopted a uniform set of standards. From 1830 until 1901, the role of overseeing weights and measures was carried out by the Office of Standard Weights and Measures, which

4140-431: The standard by NSA). NIST responded to the allegations, stating that "NIST works to publish the strongest cryptographic standards possible" and that it uses "a transparent, public process to rigorously vet our recommended standards". The agency stated that "there has been some confusion about the standards development process and the role of different organizations in it...The National Security Agency (NSA) participates in

4209-415: The surreptitious decryption of data. Both papers report that the NSA worked covertly to get its own version of SP 800-90 approved for worldwide use in 2006. The whistle-blowing document states that "eventually, NSA became the sole editor". The reports confirm suspicions and technical grounds publicly raised by cryptographers in 2007 that the EC-DRBG could contain a kleptographic backdoor (perhaps placed in

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4278-524: The temperature compensation of refined petroleum products, despite noting that these two values are not exactly consistent with each other. The ISO 13443 standard reference conditions for natural gas and similar fluids are 288.15 K (15.00 °C; 59.00 °F) and 101.325 kPa; by contrast, the American Petroleum Institute adopts 60 °F (15.56 °C; 288.71 K). Before 1918, many professionals and scientists using

4347-791: The term "standard conditions for temperature and pressure", despite its semantic near identity when interpreted literally). However, what is a "standard" laboratory temperature and pressure is inevitably geography-bound, given that different parts of the world differ in climate, altitude and the degree of use of heat/cooling in the workplace. For example, schools in New South Wales , Australia use 25 °C at 100 kPa for standard laboratory conditions. ASTM International has published Standard ASTM E41- Terminology Relating to Conditioning and hundreds of special conditions for particular materials and test methods . Other standards organizations also have specialized standard test conditions. It

4416-431: The term with older "normal conditions", or "NC". In special cases this can lead to confusion and errors. Good practice always incorporates the reference conditions of temperature and pressure. If not stated, some room environment conditions are supposed, close to 1 atm pressure, 273 K (0 °C), and 0% humidity. In chemistry, IUPAC changed its definition of standard temperature and pressure in 1982: NIST uses

4485-523: Was $ 992 million, and it also received $ 610 million as part of the American Recovery and Reinvestment Act . NIST employs about 2,900 scientists, engineers, technicians, and support and administrative personnel. About 1,800 NIST associates (guest researchers and engineers from American companies and foreign countries) complement the staff. In addition, NIST partners with 1,400 manufacturing specialists and staff at nearly 350 affiliated centers around

4554-615: Was almost universally used by the oil and gas industries worldwide. The above definitions are no longer the most commonly used in either system of units. Many different definitions of standard reference conditions are currently being used by organizations all over the world. The table below lists a few of them, but there are more. Some of these organizations used other standards in the past. For example, IUPAC has, since 1982, defined standard reference conditions as being 0 °C and 100 kPa (1 bar), in contrast to its old standard of 0 °C and 101.325 kPa (1 atm). The new value

4623-553: Was named the National Bureau of Standards . The Articles of Confederation , ratified by the colonies in 1781, provided: The United States in Congress assembled shall also have the sole and exclusive right and power of regulating the alloy and value of coin struck by their own authority, or by that of the respective states—fixing the standards of weights and measures throughout the United States. Article 1, section 8, of

4692-719: Was part of the Survey of the Coast—renamed the United States Coast Survey in 1836 and the United States Coast and Geodetic Survey in 1878—in the United States Department of the Treasury . In 1901, in response to a bill proposed by Congressman James H. Southard (R, Ohio), the National Bureau of Standards was founded with the mandate to provide standard weights and measures, and to serve as

4761-619: Was realigned by reducing the number of NIST laboratory units from ten to six. NIST Laboratories include: Extramural programs include: NIST's Boulder laboratories are best known for NIST‑F1 , which houses an atomic clock . NIST‑F1 serves as the source of the nation's official time. From its measurement of the natural resonance frequency of cesium —which defines the second —NIST broadcasts time signals via longwave radio station WWVB near Fort Collins , Colorado, and shortwave radio stations WWV and WWVH , located near Fort Collins and Kekaha, Hawaii , respectively. NIST also operates

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