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54-648: The Small Box Respirator (SBR) was a British gas mask of the First World War and a successor to the Large Box Respirator. In late 1916, the respirator was introduced by the British with the aim to provide reliable protection against chlorine and phosgene gases. The respirator offered a first line of defence against these. The use of mustard gas , was begun by the Germans; a vesicant ("blister agent") that burnt

108-407: A device that contained elements that allowed breathing through a nose and mouthpiece, inhalation of air through a bulb-shaped filter, and a vent to exhale air back into the atmosphere. First Facts states that a "gas mask resembling the modern type" was patented by Lewis Phectic Haslett of Louisville, Kentucky , who received a patent on June 12, 1849. U.S. patent #6,529 issued to Haslett, described

162-417: A face mask made of rubberized fabric connected by a rubber fabric hose to a canister made of tinplate containing a chemical absorbent. The respirator mask is light in weight and is made from khaki cotton fabric that is plated with a thin layer of black rubber. Khaki cotton tape, located in the middle of forehead region of the mask, connects to black elastic strips from the cheeks to ascertain a suitable fit for

216-404: A good fit. Crucially, it is connected to a filter cartridge near the mouth either directly, or via a flexible hose. Some models contain drinking tubes which may be connected to a water bottle. Corrective lens inserts are also available for users who require them. Masks are typically tested for fit before use. After a mask is fitted, it is often tested by various challenge agents. Isoamyl acetate ,

270-484: A mask made of chemical-absorbing fabric which fitted over the entire head: a 50.5 cm × 48 cm (19.9 in × 18.9 in) canvas hood treated with chlorine-absorbing chemicals, and fitted with a transparent mica eyepiece. Macpherson presented his idea to the British War Office Anti-Gas Department on May 10, 1915; prototypes were developed soon after. The design was adopted by

324-403: A negatively charged substrate may be used. Examples of substrates include activated carbon , and zeolites . This effect can be very simple and highly effective, for example using a damp cloth to cover the mouth and nose while escaping a fire. While this method can be effective at trapping particulates produced by combustion, it does not filter out harmful gases which may be toxic or which displace

378-424: A resin can be tailored to a particular toxic group. When the reactive substance comes in contact with the resin, it will bond to it, removing it from the air stream. It may also exchange with a less harmful substance at this site. Though it was crude, the hypo helmet was a stopgap measure for British troops in the trenches that offered at least some protection during a gas attack. As the months passed and poison gas

432-515: A string to hold the mask in to the face, and was thus an improvement to the hand-held cloth. However, it was of fragile construction, required training to use effectively, and largely immobilized its wearers because they were concerned about the mask coming loose. The Black Veil Respirator was soon replaced by the British Smoke Hood , an over the head canvas hood treated with chlorine-absorbing chemicals, invented by Cluny MacPherson . Following

486-405: A synthetic banana flavourant, and camphor are often used as innocuous challenge agents. In the military, teargases such as CN , CS , and stannic chloride in a chamber may be used to give the users confidence in the efficacy of the mask. The protection of a gas mask comes with some disadvantages. The wearer of a typical gas mask must exert extra effort to breathe, and some of the exhaled air

540-474: Is delivered. According to Popular Mechanics , "The common sponge was used in ancient Greece as a gas mask..." In 1785, Jean-François Pilâtre de Rozier invented a respirator . Primitive respirator examples were used by miners and introduced by Alexander von Humboldt in 1799, when he worked as a mining engineer in Prussia . The forerunner to the modern gas mask was invented in 1847 by Lewis P. Haslett ,

594-558: Is further classified by NIOSH air filtration ratings . A filter type that can protect against multiple hazards is notated with the European symbols concatenated with each other. Examples include ABEK, ABEK-P3, and ABEK-HgP3. A2B2E2K2-P3 is the highest rating of filter available. An entirely different "multi/CBRN" filter class with an olive color is used in the US. Filtration may be aided with an air pump to improve wearer comfort. Filtration of air

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648-434: Is only possible if there is sufficient oxygen in the first place. Thus, when handling asphyxiants , or when ventilation is poor or the hazards are unknown, filtration is not possible and air must be supplied (with a SCBA system) from a pressurized bottle as in scuba diving. A modern mask typically is constructed of an elastic polymer in various sizes. It is fitted with various adjustable straps which may be tightened to secure

702-464: Is re-inhaled due to the dead space between the facepiece and the user's face. The exposure to carbon dioxide may exceed its OELs (0.5% by volume/9 grammes per cubic metre for an eight-hour shift; 1.4%/27 grammes per m for 15 minutes' exposure) by a factor of many times: for gas masks and elastomeric respirators , up to 2.6% ); and in case of long-term use, headache , dermatitis and acne may appear. The UK HSE textbook recommends limiting

756-595: The Second Battle of Ypres , Belgium on April 22, 1915. An immediate response was cotton wool wrapped in muslin, issued to the troops by May 1. This was followed by the Black Veil Respirator , invented by John Scott Haldane , which was a cotton pad soaked in an absorbent solution which was secured over the mouth using black cotton veiling. Seeking to improve on the Black Veil respirator, Cluny Macpherson created

810-407: The U.S. Army Chemical Corps found that the level in the filter was acceptable, but suggest caution when using, as it is a carcinogen . The filter is selected according to the toxic compound. Each filter type protects against a particular hazard and is color-coded: Particle filters are often included, because in many cases the hazardous materials are in the form of mist, which can be captured by

864-620: The British Army and introduced as the British Smoke Hood in June 1915; Macpherson was appointed to the War Office Committee for Protection against Poisonous Gases. More elaborate sorbent compounds were added later to further iterations of his helmet ( PH helmet ), to defeat other respiratory poison gases used such as phosgene , diphosgene and chloropicrin . In summer and autumn 1915, Edward Harrison , Bertram Lambert and John Sadd developed

918-508: The British began issuing cotton wool wrapped in muslin to its troops by 3 May. This was followed by the Black Veil Respirator, invented by John Scott Haldane. The Black Veil was a cotton pad soaked in an absorbent solution which was secured over the mouth using black cotton veiling. The mask was treated in a solution of sodium hyposulphate , sodium carbonate , glycerine and water. The solution retained sufficient moisture so that it

972-468: The Iran Yasa factories. Absorption is the process of being drawn into a (usually larger) body or substrate, and adsorption is the process of deposition upon a surface. This can be used to remove both particulate and gaseous hazards. Although some form of reaction may take place, it is not necessary; the method may work by attractive charges . For example, if the target particles are positively charged,

1026-528: The Large Box Respirator. This canister gas mask had a tin can containing the absorbent materials by a hose and began to be issued in February 1916. A compact version, the Small Box Respirator , was made a universal issue from August 1916. In the first gas masks of World War I, it was initially found that wood charcoal was a good absorbent of poison gases. Around 1918, it was found that charcoals made from

1080-718: The atmosphere. For reasons of civil defence and personal protection, individuals often buy gas masks since they believe that they protect against the harmful effects of an attack with nuclear, biological, or chemical ( NBC ) agents, which is only partially true, as gas masks protect only against respiratory absorption. Most military gas masks are designed to be capable of protecting against all NBC agents, but they can have filter canisters proof against those agents (heavier) or only against riot control agents and smoke (lighter and often used for training purposes). There are lightweight masks solely for protection against riot-control agents and not for NBC situations. Although thorough training and

1134-466: The availability of gas masks and other protective equipment can nullify the casualty-causing effects of an attack by chemical agents, troops who are forced to operate in full protective gear are less efficient in completing tasks, tire easily, and may be affected psychologically by the threat of attack by those weapons. During the Cold War , it was seen as inevitable that there would be a constant NBC threat on

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1188-489: The battlefield and so troops needed protection in which they could remain fully functional; thus, protective gear and especially gas masks have evolved to incorporate innovations in terms of increasing user comfort and compatibility with other equipment (from drinking devices to artificial respiration tubes, to communications systems etc.). During the Iran–Iraq War (1980–88), Iraq developed its chemical weapons program with

1242-406: The carrier. The circular eye pieces are set in metal rims that are consistent of celloid which is sealed on with rubber sealant. A circular wired nose clip with rubber covered jaws sits between the internal region of the eyes. The mask contains an internal mouthpiece with an exhale valve made of black rubber consisting of a flange to fit both mouth and teeth. The mouthpiece is joined by a brass tube to

1296-466: The chlorine gas; issues later presented when the helmets could not withstand the effects of the phosgene gas . Chlorine was readily detected in battles as the gas tainted a yellowish green cloud and had a pungent odour. The situation became problematic on the introduction of the mixed phosgene and chlorine as phosgene is colourless and smells of freshly cut hay. Phosgene was up to six times as potent than chlorine and did not suggest any urgent symptoms that

1350-421: The development of chemical agents in warfare, filling the need to protect against ever more deadly threats, biological weapons, and radioactive dust in the nuclear era. However, for agents that cause harm through contact or penetration of the skin, such as blister agent or nerve agent , a gas mask alone is not sufficient protection, and full protective clothing must be worn in addition to protect from contact with

1404-452: The earlier and less effective gas masks, the PH helmet . The PH helmet was used throughout early 1916 by British troops in which was designed to be tucked under the shirt of the wearer. The masks were an evolution of the P Helmet, and were effective against phosgene gas by adding hexamine to sodium phenate solution which acted as an absorbent to the phosgene gas. Both equipment were to be present on

1458-457: The first "Inhaler or Lung Protector" that filtered dust from the air. Early versions were constructed by the Scottish chemist John Stenhouse in 1854 and the physicist John Tyndall in the 1870s. Another early design was the "Safety Hood and Smoke Protector" invented by Garrett Morgan in 1912, and patented in 1914. It was a simple device consisting of a cotton hood with two hoses which hung down to

1512-402: The floor, allowing the wearer to breathe the safer air found there. In addition, moist sponges were inserted at the end of the hoses in order to better filter the air. The First World War brought about the first need for mass-produced gas masks on both sides because of extensive use of chemical weapons . The German army successfully used poison gas for the first time against Allied troops at

1566-465: The front lines, a special type of gas mask was developed that dogs were trained to wear. Other gas masks were developed during World War I and the time following for horses in the various mounted units that operated near the front lines. In America, thousands of gas masks were produced for American as well as Allied troops. Mine Safety Appliances was a chief producer. This mask was later used widely in industry. The British Respirator, Anti-Gas (Light)

1620-419: The gas mask prior to 1915s development of the small box respirator were crude and ineffective as no troops had yet experienced poison warfare. One of the first gas masks seen in the early part of the war was the British hypo helmet , after recent failure and ineffectiveness of the black veil respirator. The helmet was intended to replace the black veil in order to effectively protect against chlorine attacks. Yet,

1674-825: The help of European countries such as Germany and France and used them in a large scale against Iranians and Iraqi Kurds. Iran was unprepared for chemical warfare. In 1984, Iran received gas masks from the Republic of Korea and East Germany , but the Korean masks were not suited for the faces of non- East Asian people , the filter lasted for only 15 minutes, and the 5,000 masks bought from East Germany proved to be not gas masks but spray-painting goggles. As late as 1986, Iranian diplomats still travelled in Europe to buy active charcoal and models of filters to produce defensive gear domestically. In April 1988, Iran started domestic production of gas masks by

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1728-514: The mask provided unreliable protection as the eye pieces were extremely fragile. The protective valve of the Hypo Helmet was vulnerable and prone to breaking. The helmet, much like the black veil, was dipped in anti-gas chemicals such as sodium hyposulphite, washing soda , glycerine and water. The choice of chemicals used was refined to develop better and more effective masks. The helmet was made from viyella (cotton wool blend) and flannel fabric that

1782-475: The oxygen required for survival. Gas masks have a useful lifespan limited by the absorbent capacity of the filter. Filters cease to provide protection when saturated with hazardous chemicals, and degrade over time even if sealed. Most gas masks have sealing caps over the air intake and are stored in vacuum-sealed bags to prevent the filter from degrading due to exposure to humidity and pollutants in normal air. Unused gas mask filters from World War II may not protect

1836-406: The particle filter before entering the chemical adsorber. In Europe and jurisdictions with similar rules such as Russia and Australia, filter types are given suffix numbers to indicate their capacity. For non-particle hazards, the level "1" is assumed and a number "2" is used to indicate a better level. For particles (P), three levels are always given with the number. In the US, only the particle part

1890-464: The phosgene mixed chlorine gas. Small Box Respirators lowered mortality rates significantly; for this reason the creation and usage of the mustard gas, a vesicant that burned the skin, was introduced as the new weapon of chemical warfare in 1917. Canadian troops began to receive small box respirators in late November 1916. While the respirators acted as the first line of defence in some British troops, other Canadian and some British troops were still using

1944-510: The poison gases. The Small Box Respirators were introduced into British and Imperial forces on the Western Front in 1916 and issue was complete early in 1917. The first use of phosgene and chlorine gas in combination had been on 19 December 1915, when it was used against French and Canadian units in the Second Battle of Ypres . It was used in six attacks up to August 1916. British anti-gas helmets - P then PH and PHG - were appointed to repel

1998-437: The respirator. The respirator could be worn above the eyes to protect against tear gas. The structure and material of the respirator made it effective for about five minutes against the regular dosage concentrations of chlorine attacks. The mask was issued at 20 May 1915. A more effective respirator that could last longer was needed; the hypo helmet was created in hopes it would replace the inferior respirator. Earlier versions of

2052-457: The rubberized hose leading to the canister. The rubber hose is around 30 cm in length and is made of vulcanized stockinette fabric making the hose flexible and strong. The canister, which was oval in cross section, contained cotton and wire gauze filters (introduced in April 1917 to catch chlorarsine compound particulates) with charcoal and quicklime , later charcoal and soda lime to absorb

2106-510: The shells and seeds of various fruits and nuts such as coconuts , chestnuts , horse-chestnuts , and peach stones performed much better than wood charcoal . These waste materials were collected from the public in recycling programs to assist the war effort. The first effective filtering activated charcoal gas mask in the world was invented in 1915 by Russian chemist Nikolay Zelinsky . Also in World War I, since dogs were frequently used on

2160-413: The skin of individuals that were exposed to it. Death rates were high with exposure to both the mixed phosgene, chlorine and mustard gas, however with soldiers having readily available access to the small box respirator, death rates had lowered significantly. Light and reasonably fitting, the respirator was a key piece of equipment to protect soldiers on the battlefield. The small box respirator consists of

2214-505: The standard into the 1930s. Panoramic lenses were not popular until the 1930s, but there are some examples of those being used even during the war (Austro-Hungarian 15M). Later, stronger polycarbonate came into use. Some masks have one or two compact air filter containers screwed onto inlets, while others have a large air filtration container connected to the gas mask via a hose that is sometimes confused with an air-supplied respirator in which an alternate supply of fresh air (oxygen tanks)

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2268-410: The troop members during battle. It became an increasing issue that PH helmets were being dropped and lost during battle; an estimated 9 million PH helmets were dropped while barely any respirators were lost. Canadian and British troops were not convinced that double the protection was needed. Both masks were liable to damage and therefore it became necessary to have both masks . The Small Box Respirators

2322-479: The use of respirators without air supply (that is, not PAPR ) to one hour. This principle relies on substances harmful to humans being usually more reactive than air. This method of separation will use some form of generally reactive substance (for example an acid ) coating or supported by some solid material. An example is synthetic resins . These can be created with different groups of atoms (usually called functional groups ) that have different properties. Thus

2376-580: The wearer at all, and could be harmful if worn due to long-term changes in the chemical composition of the filter. Some World War II and Soviet Cold War gas mask filters contained chrysotile asbestos or crocidolite asbestos . not known to be harmful at the time. It is not reliably known for how long the materials were used in filters. Typically, masks using 40 mm connections are a more recent design. Rubber degrades with time, so boxed unused "modern type" masks can be cracked and leak. The US C2 canister (black) contains hexavalent chromium ; studies by

2430-401: Was associated with the coughing and discomfort that chlorine did. Psychological impacts of the gas had resulted in unexplained anxiety attacks which would cause men to tear off their gas masks to breathe correctly exposing them to the gas. Soldiers that were affected by the gas, did not recall feeling symptoms until hours later. 85% of the fatalities that occurred due to chemical weapons, was from

2484-446: Was criticised by troops. The respirator restricted performance as it presented a very unnatural way of breathing during heavy activity of troops on the battlefield. The respirator came in six different sizes and had to be individually fitted to each man, and to be effective the fit had to checked constantly. The eye pieces were very prone to fogging and misting obstructing vision and the nose clip caused extreme discomfort. The flexible hose

2538-466: Was developed in 1943 by the British. It was made of plastic and rubber-like material that greatly reduced the weight and bulk compared to World War I gas masks, and fitted the user's face more snugly and comfortably. The main improvement was replacing the separate filter canister connected with a hose by an easily replaceable filter canister screwed on the side of the gas mask. Also, it had replaceable plastic lenses. Gas mask development since has mirrored

2592-881: Was issued to troops by 6 June 1915. The later and more refined gas mask in the form of the Large Box Respirator was developed and issued by April 1916 to specialist troops such as machine gunners, signallers and artillery. This was followed by the Small Box Respirator. Gas mask Airborne toxic materials may be gaseous (for example, chlorine or mustard gas ), or particulates (such as biological agents ). Many filters provide protection from both types. The first gas masks mostly used circular lenses made of glass , mica or cellulose acetate to allow vision. Glass and mica were quite brittle and needed frequent replacement. The later Triplex lens style (a cellulose acetate lens sandwiched between glass ones) became more popular, and alongside plain cellulose acetate they became

2646-476: Was loosely woven material, provided better absorption of the solution and allowed troop members to breathe effectively. A long piece of black veil cotton was folded to form a large sheath pocket to retain the chemical absorbents. The cotton veil was then wrapped around the user's head and tied. The chemical absorbents consisting of anti gas chemicals such as sodium hyposulfite , washing soda, Glycerine acetate and water allowed for consistent and dense moisturizing in

2700-399: Was refined from material made from mica, which was brittle and damage prone. The helmet was hot and uncomfortable as the fitting required users to tuck inside uniforms. The helmet was a large improvement on the black veil but it was difficult for soldiers to use weapons with the helmet on. The helmet accumulated carbon dioxide in the uniforms of the users as no expiration valve was present. It

2754-402: Was unnecessary to dip the mask in a solution prior to use, so long as it was stored in its purpose-built waterproof satchel. The veiling could be drawn up to cover the eyes, providing some protection against lachrymatory agents ; however, the mask itself still only provided limited protection against chlorine gas. First issued on 20 May 1915, the Black Veil had a pouch for the pad to sit in and

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2808-506: Was used more often, more sophisticated gas masks were developed and introduced. There are two main difficulties with gas mask design: Black Veil Respirator The Black Veil Respirator was an early British gas mask designed by John Scott Haldane and introduced in May 1915. The German army used chlorine as a poison gas for the first time against Allied troops at the Second Battle of Ypres on 22 April 1915. As an immediate response,

2862-487: Was used on the evening of 22 April 1915 in Belgium, close to Ypres, by British troops. Home made respirators, known as the black veil, comprised cotton wool that was wrapped in either muslin or flannelette . The mask was ineffective and almost completely useless when dry. When the mask was either moist and wet from being soaked in the absorbent solution, it formed an airtight fit over the troops mouth and noise. The cotton, which

2916-436: Was vulnerable to damage and then let gas in. Adjusting the gas mask was problematic, death could be the result if it was not worn correctly; soldiers had compulsory practice with the mask before using it in combat. The respirator caused intensive wheezing and extreme heat and exhaustion could result in suffocation-like symptoms. The first and proper respirator developed was the Black Veil Respirator by John Scott Haldane . It

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