PH helmet 2491779 215329790 2008-05-27T18:52:55Z DOI bot 6652755 Citation maintenance. You can [[WP:DOI|use this bot]] yourself! Please [[User:DOI_bot/bugs|report any bugs]]. [[Image:Vickers machine gun crew with gas masks.jpg|right|thumb|200px|British Vickers machine gun crew wearing PH-type anti-gas helmets near Ovillers during the Battle of the Somme, July 1916]] [[Image:Gas Mask 1915 RCR Museum.JPG|thumb|200px|PH-type helmet in Royal Canadian Regiment Museum]] The '''P helmet''', '''PH helmet''' and '''PHG helmet''' were early types of [[gas mask]] issued by the [[British Army]] in the [[First World War]], to protect troops against [[chlorine]], [[phosgene]] and [[tear gas]]es. Rather than having a separate filter for removing the toxic chemicals, they consisted of a gas-permeable hood worn over the head which was treated with chemicals. The P (or Phenate) Helmet, officially called the '''Tube Helmet''', <ref>{{cite web | url = http://www.westernfrontassociation.com/thegreatwar/articles/weapons/gasapparatus.htm | title = The Apparatus Of Gas Warfare On The Western Front In The Great War | work = The Western Front Association | accessdate=2008-01-21}}</ref> appeared in July 1915,<ref>{{cite_journal | journal =Chemical warfare | title=Gas mask development | author = CWS Barker | volume=12 | issue = 7 | pages=11–15 | year=1926 | url=http://www33.brinkster.com/iiiii/gasmask/development.html}}</ref> replacing the simpler [[Hypo Helmet]]. It featured two [[mica]] eyepieces instead of the single visor of its predecessor, and added an exhaust valve fed from a metal tube which the wearer held in his mouth. The exhaust valve was needed because a double layer of flannel &ndash; one treated and one not &ndash; was needed because the solution attacked the fabric. It had flannel layers of cloth-dipped in [[sodium phenolate]] and [[glycerin]] and protected against chlorine and phosgene, but not against tear gas. Around 9 million were made. The PH Helmet (Phenate Hexamine) replaced it in October 1915, and added hexamethylene tetramine, which greatly improved protection against phosgene<ref>[http://www.gutenberg.org/dirs/etext98/rrhin10.txt The Riddle of the Rhine: Chemical Strategy in Peace and War], Victor LeFebure, at Project Gutenberg</ref> and added protection against [[hydrogen cyanide|hydrocyanic acid]].<ref>[http://www.eustis.army.mil/dtpmsec/NBC_School/Mask%20History.pdf History of the U.S. Army's protective mask]</ref> Around 14 million were made and it remained in service until the end of the war by which time it was relegated to second line use. The PHG Helmet appeared in January 1916 and was similar to the PH Helmet but had a facepiece made of rubber sponge to add protection against tear gas. Around one and a half million were produced in 1916-1917. It was finally superseded by the [[small box respirator]] in February 1916, which was much more satisfactory against high concentrations of phosgene or lachrymators. ==References== <references/> ==External links== * [http://www.gasmasks.net/database/uk/uk.htm The gas mask database: The UK] [[Category:Masks]] [[Category:Chemical warfare]] [[Category:World War I military equipment of the United Kingdom]] {{UK-mil-stub}}