World Library  
Flag as Inappropriate
Email this Article

Inch of water

Article Id: WHEBN0011101076
Reproduction Date:

Title: Inch of water  
Author: World Heritage Encyclopedia
Language: English
Subject: Pipe organ, Centimetre of water, Miner's inch, Pressure regulator, Pounds per square inch
Publisher: World Heritage Encyclopedia

Inch of water

Inches of water, wc, inch water column (inch WC), inAq, Aq, or inH2O is a non-SI unit for pressure. The units are by convention and due to the historical measurement of certain pressure differentials. It is used for measuring small pressure differences across an orifice, or in a pipeline or shaft.[1] Inches of water can be converted to a pressure unit using the formula for pressure head.

It is defined as the pressure exerted by a column of water of 1 inch in height at defined conditions for example 39 °F (4 °C) at the standard acceleration of gravity; 1 inAq is approximately equal to 249 pascals at 0 °C.

Alternative standard conditions in uncommon usage are 60 °F, or 68 °F (20 °C), and depends on industry standards rather than on international standards.

In North America, air and other industrial gasses are often measured in inches of water when at low pressure. This is in contrast to inches of mercury or psi for larger pressures. One usage is in the measurement of air ("wind") that supplies a pipe organ and is referred simply as inches. It is also used in natural gas distribution for measuring utilization pressure (U.P., i.e. the residential point of use) which is typically between 6 and 7 inches WC (6~7" WC) or about 0.25 psi.

1 inAq ≈ .036 psi, or 27.7 inAq ≈ 1 psi.

1 inH2 = 248.84 pascals (60 °F)[2]
= 2.4884 mbar or hectopascals (60 °F)
= 2.54 cmH2O (4 °C)
≈ 0.0024558598569 atm
≈ 1.86645349124 torr or mmHg (0 °C)
≈ 0.0734824209149 inHg (0 °C)
≈ 0.0360911906567 PSI

See also


This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from World eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.