Centimetre or millimetre of water

A centimetre or millimetre of water (US spelling centimeter or millimeter of water) are less commonly used measures of pressure based on the pressure head of water.

Centimetre of water

centimetre of water
Unit ofPressure
SymbolcmH2O
Conversions
1 cmH2O in ...... is equal to ...
   SI units   98.0665 Pa
   English Engineering units   1.422334×10−2 psi

A centimetre of water[1] is a unit of pressure. It may be defined as the pressure exerted by a column of water of 1 cm in height at 4 °C (temperature of maximum density) at the standard acceleration of gravity, so that 1 cmH2O (4°C) = 999.9720 kg/m3 × 9.80665 m/s2 × 1 cm = 98.063754138 Pa ≈ 98.0638 Pa, but conventionally a nominal maximum water density of 1000 kg/m3 is used, giving 98.0665 Pa.

The centimetre of water unit is frequently used to measure the central venous pressure, the intracranial pressure while sampling cerebrospinal fluid, as well as determining pressures during mechanical ventilation or in water supply networks (then usually in metres water column). It is also a common unit of pressure in the speech sciences. This unit is commonly used to specify the pressure to which a CPAP machine is set after a polysomnogram.

1 cmH2O (conventional) = 98.0665 pascals[2]
= 0.01 metre water (mH2O), metre water column (m wc) or metre water gauge (m wg)
= 10 mm wg
= 0.980665 mbar or hPa
≈ 0.3937008 inH2O
≈ 0.0009678411 atm
≈ 0.7355592 torr
≈ 0.7355591 mm Hg
≈ 0.02895902 inHg
≈ 0.01422334 psi

Millimetre of water

millimetre of water
Unit ofPressure
SymbolmmH2O
Conversions
1 mmH2O in ...... is equal to ...
   SI units   9.80665 Pa
   English Engineering units   1.422334×10−3 psi

Millimetre of water (US spelling millimeter of water)[3] is a unit of pressure. It may be defined as the pressure exerted by a column of water of 1 mm in height at 4 °C (temperature of maximum density) at the standard acceleration of gravity, so that 1 mmH2O (4 °C) = 999.9720 kg/m3 × 9.80665 m/s2 × 1 mm = 9.8063754138 Pa ≈ 9.80638 Pa, but conventionally a nominal maximum water density of 1000 kg/m3 is used, giving 9.80665 Pa.

1 mmH2O (conventional) = 9.80665 pascals[2]
= 0.001 metre water (mH2O), metre water column (m.wc) or metre water gauge (m wg)
= 0.1 cm wg
= 0.0980665 mbar or hPa
≈ 0.03937008 inH2O
≈ 9.678411×10−5 atm
≈ 0.07355592 torr
≈ 0.07355591 mmHg
≈ 0.002895902 inHg
≈ 0.001422334 psi

In limited and largely historic contexts it may vary with temperature, using the equation:

P = ρ·g·h/1000,
where
P: pressure in Pa
ρ: density of water (conventionally 1000 kg/m3 at 4 °C)
g: acceleration due to gravity (conventionally 9.80665 m/s2 but sometimes locally determined)
h: water height in millimetres.

The unit is often used to describe how much water rainwear or other outerwear can take or how much water a tent can resist without leaking.

See also

References

  1. ^ NOTE: A centimetre of water is abbreviated as cmH2O or cm H2O.
  2. ^ a b nist.gov – Guide for the Use of the International System of Units (SI) page 47, 2008 Edition
  3. ^ NOTE: Millimetre of water is also sometimes addressed as : millimetres water column, abbreviated as mmwg, mmH2O, or mmwc.

Read other articles:

Daily Times of Nigeria

Dailytimes NigeriaTipeMedia publicationFormatCetak dan daringPenerbitFolio CommunicationsRedaksiSam NzehDidirikan6 Juni 1925BahasaInggrisPusatLagos, Negara Bagian Lagos, NigeriaSirkulasi surat kabarSeluruh negeriSitus webwww.dailytimes.ng Dailytimes Nigeria adalah sebuah surat kabar dengan markas besar di Lagos. Pada masa puncaknya, pada 1970an, surat kabar tersebut menjadi salah satu bisnis milik lokal paling sukses di Afrika.[1] Referensi ^ Ismail Babatunde Jose: Newspaper editor wh...

 

Daniel Goldberg

Pour les articles homonymes, voir Daniel Goldberg et Goldberg. Daniel Goldberg Daniel Goldberg en 2012. Fonctions Président de l’Union nationale interfédérale des œuvres et organismes privés non lucratifs sanitaires et sociaux En fonction depuis le 22 septembre 2022(1 an, 6 mois et 6 jours) Élection 22 septembre 2022 Prédécesseur Patrick Doutreligne Député français 20 juin 2012 – 20 juin 2017(5 ans) Élection 17 juin 2012 Circonscription 10e de la Seine-Sai...

 

Kent

County of England This article is about the county in England. For other uses, see Kent (disambiguation). Ceremonial county in EnglandKentCeremonial countyThe White Cliffs of Dover, stained glass depicting Thomas Becket in Canterbury Cathedral, and Rochester Castle Ceremonial Kent within England Ceremonial Kent Historic Kent in the British Isles Historic KentCoordinates: 51°12′N 0°42′E / 51.200°N 0.700°E / 51.200; 0.700Sovereign stateUnited KingdomConstituent c...

Человек прямоходящий

† Человек прямоходящий Научная классификация Домен:ЭукариотыЦарство:ЖивотныеПодцарство:ЭуметазоиБез ранга:Двусторонне-симметричныеБез ранга:ВторичноротыеТип:ХордовыеПодтип:ПозвоночныеИнфратип:ЧелюстноротыеНадкласс:ЧетвероногиеКлада:АмниотыКлада:Синапсиды�...

 

Laccophilinae

Subfamily of beetles Laccophilinae Laccophilus maindroni Scientific classification Domain: Eukaryota Kingdom: Animalia Phylum: Arthropoda Class: Insecta Order: Coleoptera Family: Dytiscidae Subfamily: LaccophilinaeGistel, 1856 Laccophilinae is a subfamily of ground and water beetles in the family Dytiscidae. There are at least 410 described species in Laccophilinae.[1][2] Genera Africophilus Guignot, 1948 Agabetes Crotch, 1873 Australphilus Watts, 1978 Japanolaccophilus Satô,...

 

Vyškov

Questa voce sull'argomento centri abitati della Moravia Meridionale è solo un abbozzo. Contribuisci a migliorarla secondo le convenzioni di Wikipedia. Vyškovcittà Vyškov – Veduta LocalizzazioneStato Rep. Ceca Regione Moravia Meridionale DistrettoVyškov AmministrazioneSindacoMichael Sneobova TerritorioCoordinate49°16′37.99″N 16°59′55.68″E / 49.27722°N 16.9988°E49.27722; 16.9988 (Vyškov)Coordinate: 49°16′37.99″N 16°59′55.68″E࿯...

Hothfield Common

Nature reserve in Kent, England Hothfield CommonSite of Special Scientific InterestLocationKentGrid referenceTQ 968 458[1]InterestBiologicalArea56.5 hectares (140 acres)[1]Notification1985[1]Location mapMagic Map Hothfield Common is a 56.5-hectare (140-acre) biological Site of Special Scientific Interest north-east of Ashford in Kent.[1][2] It is also a Local Nature Reserve,[3][4] and is part of the 86-hectare (210-acre) Hothfield Heathl...

 

哈萨克斯坦总统

此条目序言章节没有充分总结全文内容要点。 (2019年3月21日)请考虑扩充序言，清晰概述条目所有重點。请在条目的讨论页讨论此问题。 哈萨克斯坦總統哈薩克總統旗現任Қасым-Жомарт Кемелұлы Тоқаев卡瑟姆若马尔特·托卡耶夫自2019年3月20日在任任期7年首任努尔苏丹·纳扎尔巴耶夫设立1990年4月24日（哈薩克蘇維埃社會主義共和國總統） 哈萨克斯坦 哈萨克斯坦政府...

 

الجماهيرية العربية الليبية الشعبية الاشتراكية العظمى

ليبيا الجماهيرية العربية الليبية الشعبية الاشتراكية العظمى الجماهيرية العربية الليبية 1977 – 2011 الجماهيرية العربية الليبية الشعبية الاشتراكية العظمىعلم الجماهيرية العربية الليبية الشعبية الاشتراكية العظمىشعار النشيد : الله أكبر عاصمة طرابلس نظام الحكم جماهيري...

جرانيت

غرانيتمعلومات عامةصنف فرعي من صخر جرانيتيplutonic rock (en) [1] سُمِّي باسم أسوانألبيروسو المواد المستخدمة مرو[2]بلاجيوكليز[2]حجر القمر[2] الجوائز  Rock of the Year (en) (2007) صلابة موس 6 ممثلة بـ اضمحلال نشاط إشعاعي[3] تعديل - تعديل مصدري - تعديل ويكي بيانات صورة مقربة للج�...

 

Richard Florida

American urban studies theorist For other uses, see Florida (disambiguation). Richard FloridaFlorida in 2006Born1957 (age 66–67)Newark, New Jersey, U.S.SpouseRana FloridaAcademic backgroundAlma materRutgers College (BA)Columbia University (M.Phil., PhD)Academic workInstitutionsHeinz CollegeGeorge Mason UniversityUniversity of TorontoMain interestsUrban policyNotable worksThe Rise of the Creative Class (2002)Who's Your City? 2008)Notable ideasCreative class Richard L. Florida (born ...

 

Epistle of James

Book of the New Testament Not to be confused with Gospel of James. Chapter numbers redirect here; for the kings, see: James I (disambiguation), James II (disambiguation), James III (disambiguation), James IV of Scotland, James IV of Majorca, James V of Scotland Part of a series onBooks of theNew TestamentPapyrus 46, one of the oldest New Testament papyri, showing 2 Cor 11:33–12:9 Gospels and Acts Four Evangelists MatthewMarkLukeJohn Lukan Acts Acts of the Apostles Epistles and Apo...

Blood (video game)

1997 video gameBloodDeveloper(s)Monolith ProductionsNightdive Studios (remaster)Publisher(s)GT InteractiveEidos Interactive (Europe)Atari (remaster)Director(s)Nick NewhardProducer(s)Matt SaettlerProgrammer(s)Peter FreeseNick NewhardDan LeeksMatt SaettlerArtist(s)Kevin KilstromComposer(s)Daniel BernsteinGuy WhitmoreEngineBuildKex Engine (remaster)Platform(s)MS-DOS, WindowsReleaseNA: March 7, 1997 (Shareware)NA: May 21, 1997 (Registered)EU: June 20, 1997NA: July 15, 1998 (One Unit Whole Blood)...

 

Saint Sarkis Cathedral, Yerevan

Saint Sarkis CathedralՍուրբ Սարգիս Մայր ԵկեղեցիSaint Sarkis CathedralReligionAffiliationArmenian Apostolic ChurchYear consecrated1842StatusactiveLocationLocationcorner of Mesrop Mashtots and Israyelian streets, Kentron District, Yerevan, ArmeniaShown within ArmeniaGeographic coordinates40°10′37″N 44°30′08″E / 40.176980°N 44.502148°E / 40.176980; 44.502148ArchitectureStyleArmenian Saint Sarkis Cathedral (Armenian: Սուրբ Սարգի�...

 

Cénotaphe du général de Lamoricière

Cénotaphe du général de LamoricièreLe cénotaphe dans le transept nord de la cathédrale de Nantes.PrésentationType Cénotaphe avec gisantArchitecte Louis BoitteSculpteur Paul DuboisMatériau marbreConstruction 1878-1879Patrimonialité Objet français classé monument historique (d) (1862)LocalisationPays FranceDépartement Loire-AtlantiqueCommune NantesCoordonnées 47° 13′ 07″ N, 1° 33′ 01″ OLocalisation sur la carte de FranceLocalisation sur...

Verein für Leibesübungen von 1899 1995-1996

Voce principale: Verein für Leibesübungen von 1899. Verein für Leibesübungen von 1899Stagione 1995-1996Sport calcio Squadra Osnabrück Allenatore Herbert Mühlenberg Regionalliga Nord5º posto Coppa di GermaniaPrimo turno 1994-1995 1996-1997 Si invita a seguire il modello di voce Questa voce raccoglie le informazioni riguardanti il Verein für Leibesübungen von 1899 nelle competizioni ufficiali della stagione 1995-1996. Indice 1 Stagione 2 Rosa 3 Organigramma societario 4 Calciomer...

 

Video game industry

Economic sector involved with the development, marketing and sales of video games This article's lead section may be too short to adequately summarize the key points. Please consider expanding the lead to provide an accessible overview of all important aspects of the article. (January 2018) Part of a series on theVideo game industry Development Producer Developer Designer Artist Programmer Design Level design Programming Engine AI Graphics Music Testing Products Video game Specialized / alter...

 

Ordine della Corona (Iran)

Ordine della Corona di PersiaNishan-i-TajGran Cordone dell'Ordine Impero PersianoTipologiaOrdine cavalleresco statale Statuscessato IstituzioneTehran, 1926 Primo capoReza Shah Pahlavi CessazioneTehran, 1979 Ultimo capoMohammad Reza Pahlavi GradiCavaliere di Gran StellaGrand'UfficialeCommendaotreUfficialeCavaliere Onorificenze iranianeOrdine più altoOrdine dei Pahlavi Ordine più bassoOrdine del Sole Nastro dell'ordine Modifica dati su Wikidata · Manuale L'Ordine della Corona fu un ordi...

Ottawa River

River in Canada This article is about the river in Canada. For other uses, see Ottawa River (disambiguation). Ottawa RiverRivière des Outaouais (French)Kichi-Sìbì (Algonquin)The Ottawa River in autumnMap of the Ottawa River drainage basinLocationCountryCanadaProvincesQuebec, OntarioPhysical characteristicsSourceLac des Outaouais • locationLac-Moselle, La Vallée-de-la-Gatineau RCM, Outaouais, Quebec, Canada • coordinates47°38′38″N 75°38�...

 

Maybe (Forse)

Pour les articles homonymes, voir Maybe. Maybe (Forse) Chanson de Valentina Monetta au Concours Eurovision de la chanson 2014 Sortie 14 Mars 2014 Durée 3 min 7 secondes Langue Anglais Auteur Mauro Balestri Compositeur Ralph Siegel Chansons représentant Saint-Marin au Concours Eurovision de la chanson Crisalide (Vola)(2013) Chain of Lights(2015)modifier Maybe (Forse) est une chanson de Valentina Monetta ; elle représente son pays Saint-Marin pour la troisième fois consécutive. ...