Inches of Water to Millibars calculator

Inches of Water to Millibars Conversion Table

Below you can generate and download as CSV, Excel, PDF or print the Inches of Water to Millibars conversion table based on your needs.

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• Inch of Water (249.09 Pa)

  Inches of water, inches of water gauge (iwg or in.w.g.), inches water column (inch wc or just wc), inAq, Aq, or inH2O is a non-SI unit for pressure. The units are conventionally used for measurement of certain pressure differentials such as small pressure differences across an orifice, or in a pipeline or shaft. Inches of water can be converted to a pressure unit using the formula for pressure head.

• Millibar (100 Pa)

  The bar is a metric unit of pressure, but is not approved as part of the International System of Units (SI). It is defined as exactly equal to 100,000 Pa, which is slightly less than the current average atmospheric pressure on Earth at sea level. The bar and the millibar were introduced by the Norwegian meteorologist Vilhelm Bjerknes, who was a founder of the modern practice of weather forecasting. The International Bureau of Weights and Measures (BIPM) lists the bar as one of the "non-SI units should have the freedom to use", but has declined to include it among the "Non-SI units accepted for use with the SI". The bar has been legally recognised in countries of the European Union since 2004. The US National Institute of Standards and Technology (NIST) deprecates its use except for "limited use in meteorology" and lists it as one of several units that "must not be introduced in fields where they are not presently used". The International Astronomical Union (IAU) also lists it under "Non-SI units and symbols whose continued use is deprecated". One Millibar is equal to 0.001 bar.