International Standard Atmosphere

<p>The International Standard Atmosphere (ISA) is a <a href="/facts/Static_atmospheric_model/EHzlURfA">static atmospheric model</a> of how the <a href="/facts/Pressure/eyc37GRG">pressure</a>, <a href="/facts/Temperature/QyGe4gmj">temperature</a>, <a href="/facts/Density/92p6hh9I">density</a>, and <a href="/facts/Viscosity/QLVfrdCz">viscosity</a> of the <a href="/facts/Earth%2527s_atmosphere/FV97Am25">Earth's atmosphere</a> change over a wide range of <a href="/facts/Altitude/B5eNVurK">altitudes</a> or <a href="/facts/Elevation/h2d0u9nd">elevations</a>. It has been established to provide a common reference for temperature and pressure and consists of tables of values at various altitudes, plus some formulas by which those values were derived. The <a href="/facts/International_Organization_for_Standardization/IacYR7Yg">International Organization for Standardization</a> (ISO) publishes the ISA as an <a href="/facts/International_standard/9R3SMtfH">international standard</a>, ISO 2533:1975. Other <a href="/facts/Standards_organization/8o7wGeYg">standards organizations</a>, such as the <a href="/facts/International_Civil_Aviation_Organization/TzrL1mLr">International Civil Aviation Organization</a> (ICAO) and the <a href="/facts/United_States_Government/VJCxUaf7">United States Government</a>, publish extensions or subsets of the same atmospheric model under their own standards-making authority.
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International Standard Atmosphere open-in-new

International Standard Atmosphere