View source for Kilogram-force per square centimetre

{{short description|Unit of pressure}}
{{Infobox unit
| bgcolor = 
| name = Kilogram-force per square centimetre
| image = Da Lat locomotive dials.JPG
| caption = Soviet-made pressure gauges using kgf/cm<sup>2</sup>
| standard = 
| quantity = [[Physics:Pressure|Pressure]]
| symbol = kgf/cm<sup>2</sup>
| symbol2 = at
| units1 = SI units
| inunits1 = {{convert|1|kgf/cm2|kPa|sigfig=7|disp=out}}
| units2 = FPS units
| inunits2 = {{convert|1|kgf/cm2|psi|sigfig=7|disp=out}}
}}
[[File:Kgcm meter wiki1.jpg|thumb|right|Pressure gauge from unknown source produced by ISGUS GmbH.]]
[[File:Kgcm meter wiki2.jpg|thumb|right|Pressure gauge from unknown source. Note the "square" instead of <sup>2</sup>. ({{lang|sv|Olja}} means "oil" in Swedish)]]

A '''kilogram-force per centimetre square''' (kgf/cm<sup>2</sup>), often just '''kilogram per square centimetre''' (kg/cm<sup>2</sup>), or '''kilopond per centimetre square''' (kp/cm<sup>2</sup>) is a deprecated unit of [[Physics:Pressure|pressure]] using metric units. It is not a part of the [[International System of Units]] (SI), the modern metric system. 1&nbsp;kgf/cm<sup>2</sup> equals 98.0665&nbsp;kPa (kilopascals). It is also known as a '''technical atmosphere''' (symbol: at).<ref>{{Cite book|url=https://books.google.com/books?id=TCLOBgAAQBAJ&q=technical+atmosphere&pg=SA3-PA12|title=CRC Handbook of Engineering Tables|last=Dorf|first=Richard C.|date=2003-11-24|publisher=CRC Press|isbn=9780203009222|language=en}}</ref><ref>{{Cite web|url=https://www.nist.gov/pml/special-publication-811|title=Special Publication 811|last=Suplee|first=Curt|date=2009-07-02|website=NIST|language=en|access-date=2019-05-17}}</ref>

The kilogram-force per square centimetre remains active as a measurement of force primarily due to older pressure measurement devices still in use.

This use of the unit of pressure provides an intuitive understanding for how a body's ''mass'' can apply ''force'' to a scale's ''surface area'' i.e.'''kilogram-force per square (centi-)metre'''. 

In SI units, the unit is converted to the SI derived unit [[Pascal (unit)|pascal]] (Pa), which is defined as one [[Newton (unit)|newton]] per square metre (N/m<sup>2</sup>). A newton is equal to 1&nbsp;kg⋅m/s<sup>2</sup>, and a [[Kilogram-force|kilogram-force]] is 9.80665&nbsp;N,<ref>[http://physics.nist.gov/Pubs/SP811/appenB9.html#PRESSURE The NIST Guide for the use of the International System of Units], ''National Institute of Standards and Technology'', 18 Oct 2011</ref> meaning that 1&nbsp;kgf/cm<sup>2</sup> equals 98.0665 kilopascals (kPa).

In some older publications, '''kilogram-force per square centimetre''' is abbreviated '''ksc''' instead of '''kg/cm<sup>2</sup>'''.

{{Pressure Units|sp=us}}

:{|
|-
|valign=top rowspan=2|1&nbsp;at&nbsp;||= 98.0665 kPa
|-
|≈ {{val|0.96784}} standard [[Physics:Atmosphere (unit)|atmosphere]]s
|}

==Ambiguity of at==
The symbol "at" clashes with that of the [[Katal|katal]] (symbol: "kat"), the SI unit of catalytic activity; a kilotechnical atmosphere would have the symbol "kat", indistinguishable from the symbol for the katal.  It also clashes with that of the non-SI unit, the attotonne, but that unit would more likely be rendered as the equivalent SI unit, the picogram.

==References==
<references/>

{{DEFAULTSORT:Kilogram-Force Per Square Centimetre}}
[[Category:Units of pressure]]
[[Category:Non-SI metric units]]

{{Sourceattribution|Kilogram-force per square centimetre}}