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{{short description|Self contained breathing apparatus providing gas to escape from a hazardous environment}}
{{more references|date=August 2023}}
[[
'''Escape breathing apparatus''', also called '''escape respirators''', '''escape sets''',
Escape breathing apparatus may be [[Air purifier|air-purifying]] escape respirators or self-contained atmosphere-supplying escape respirators. They may use a [[breathing hood]], [[facepiece]] or [[Mouthpiece (breathing apparatus)|mouthpiece]] and nose-clip as the [[user respiratory interface]]. Atmosphere-supplying apparatus may be [[rebreather]]s with a [[chemical oxygen supply|chemical]] or [[
Escape breathing apparatus are not generally intended to be used for anything other than escaping a dangerous environment.<ref name="ashsafety" /> An ''escape-only respirator'' is defined as "a respirator intended to be used only for emergency exit".<ref name="29 CFR 1910" />
==Applications==▼
[[File:US Navy 030312-N-0068T-036 Fireman Charles Phillips uses an Emergency Escape Breathing Device (EEBD) as he climbs up the emergence escape trunk while conducting a main machinery space fire drill.jpg|thumb|US Navy [[Emergency Escape Breathing Device]] (EEBD)]]▼
Escape breathing apparatus are a class of self contained atmosphere supplying or air purifying breathing apparatus for use in emergencies, intended to allow the user to pass through areas without a breathable atmosphere to a place of relative safety where the ambient air is safe to breathe. These are ambient pressure systems, and include:▼
The small open-circuit scuba [[Helicopter Aircrew Breathing Device]] has the similar purpose of providing breathing gas to escape from a ditched helicopter.▼
*[[Helicopter escape set]]▼
*[[Mine escape set]]▼
*[[Submarine escape set]]{{anchor|Submarine escape set}} ▼
*[[Amphibious Tank Escape Apparatus]]▼
*[[Smoke hood]]▼
Early escape sets were often [[rebreather]]s and were typically used to escape from [[submarine]]s that were unable to surface. Escape sets are also used ashore, in the [[mining]] industry, and by the military for escape from tanks.▼
▲The small open-circuit scuba [[Helicopter Aircrew Breathing Device]] has the similar purpose of providing breathing gas to escape from a ditched helicopter.
===Selection===
An air purification type escape respirator includes a filter or absorbent cartridge suitable for the environment in which it is intended to be used. An escape respirator that provides autonomous gas will allow the user to escape most environments that require only respiratory protection. An escape respirator provides no chemical or environmental protection to the rest of the user's body. {{cn|date=July 2023}}▼
Escape breathing apparatus have the function of allowing a person working in an environment that is normally safe, enough time to escape from respiratory hazards that may occur without sufficient warning to evacuate without respiratory protection. therefore selection relies mainly on the time required to escape, and the probability of IDLH or oxygen deficiency, rather than assigned protection factors.<ref name="NIOSH" />
Calculation of the time likely to be needed for escape and the recommended escape route is the responsibility of the employer, and should take into account the reasonably foreseeable emergencies that might require escape.
▲An air purification type escape respirator includes a filter or absorbent cartridge suitable for the environment in which it is intended to be used. They are unsuitable for escape through potentially oxygen depleted environments. An escape respirator that provides autonomous gas will allow the user to escape most environments that require only respiratory protection. They are generally available with endurance ratings from 3 to 60 minutes. 10 and 15 minutes are common specifications.<ref name="ashsafety" /><ref name="NIOSH" /> An escape respirator provides no chemical or environmental protection to the rest of the user's body, and the need for eye protection must be considered when choosing the user respiratory interface.<ref
==Types==
===Autonomous breathing gas supply===
These breathing apparatus carry a supply of breathing gas calculated to be sufficient for most users to escape within the specified time-frame.
====Rebreathers====
{{main|Rebreather}}
Atmospheric air contains about 21% [[oxygen]]. In normal breathing the body uses about 4% and replaces it with [[carbon dioxide]]. A volume of air can be breathed several times before its oxygen content is exhausted, but carbon dioxide accumulates as the oxygen is used up, and causes discomfort and respiratory distress, so it must be removed from the breathing cycle. There is also a danger that when the oxygen level is too low, the user will lose consciousness due to hypoxia, and
The absorbent used for non-regenerative carbon dioxide absorption is usually [[sodalime]], or a material based on sodalime, but in former times [[slaked lime]] or [[quicklime]] or [[caustic soda]] was sometimes used.{{cn|date=August 2023}}
Rebreathers using chemical oxygen generation can be small, light and easy to wear. They may use the [[Pendulum rebreather|pendulum]] type breathing system, which has larger dead space than a one-way [[Loop rebreather|loop]] architecture, but is simpler and cheaper to manufacture. Endurance is generally from 20 to 100 minutes Oxygen is produced by a chemical reaction between the carbon dioxide and [[potassium superoxide]] absorbent, which both removes the carbon dioxide and supplies a slightly larger volume of oxygen to replace that which was used.<ref name="ashsafety" /><ref name="MRS" />
A basic unit may use a bite-grip mouthpiece and nose clip, or may include goggles or a hood if eye protection is necessary. Some units have a cartridge to inflate the bag when first used, but this is mainly to provide a bit more volume in the counterlung, which can reduce the feeling of insufficient gas at startup when the bag is nearly empty.<ref name="ashsafety" />
These sets can offer a relatively long endurance, and may be classed as working breathing apparatus as well, in which case they may be worn to
Oxygen rebreathers can also use less reactive scrubber absorbent which only removes carbon dioxide, but must then have an alternative supply of oxygen, usually compressed gas from a high pressure cylinder.
Submarine escape sets had a mouthpiece, so the user had to also wear a [[noseclip]] to prevent breathing water through the nose. The endurance of a submarine escape set was between 15 and 45 minutes.{{cn|date=August 2023}}
====Open circuit escape breathing apparatus====
Open circuit escape breathing apparatus may be demand supplied or constant flow.<ref name="ashsafety" />
A [[positive pressure open circuit breathing apparatus]] with a [[full-face mask]] provides the highest level of protection against a toxic environment, but is relatively complex, expensive, and requires greater competence to use efficiently. They provide breathing air from a high pressure cylinder carried by the user, supplied through a [[pressure reducing regulator]] and a [[demand valve]], to a mask which covers the whole face, and must fit correctly to prevent gas wastage via leaks. The air is provided at a pressure slightly above ambient to ensure that any leaks are outwards. Recharging is simple and inexpensive. Vision through the mask is usually quite good, and voice communication is usually acceptable. Endurance depends on cylinder size and working pressure, effectiveness of the face seal, and level of exertion and anxiety of the user. 10 to 15 minutes is typical, though more is possible.<ref name="ashsafety" />
There may be difficulties with sealing over facial
Constant flow open circuit breathing apparatus delivers compressed air from a storage cylinder at about 40 litres per minute, regardless of the activity of the user. This makes the endurance accurately predictable and dependent on the cylinder volume and charging pressure. Since they are commonly provided with a hood and seal on the neck, they are tolerant of facial hair and eyeglasses, but the large hood volume and soft plastic viewport do not provide very good vision,
The air supply is typically from a 200 bar aluminium, steel or fibre-wound composite cylinder. A 2 litre cylinder will supply roughly 10 minutes endurance, and a 3 litre cylinder about 15 minutes at 35 to 37 litres per minute. A rubber neck seal helps provide a positive pressure within the hood. The total mass of a set, complete with sling carrying bag is typically in the order of 5 to 7 kg.<ref name="Draeger" />
===Continuous-flow Escape-SCBA===
▲==Applications==
{{main|Self-contained breathing apparatus#Continuous-flow}}
▲[[File:US Navy 030312-N-0068T-036 Fireman Charles Phillips uses an Emergency Escape Breathing Device (EEBD) as he climbs up the emergence escape trunk while conducting a main machinery space fire drill.jpg|thumb|US Navy [[Emergency Escape Breathing Device]] (EEBD)]]
A continuous-flow [[SCBA]], usually with hood, is a type of emergency escape breathing apparatus.<ref>{{cite book |url=https://books.google.com/books?id=1Y64oZHP9zYC | title=NIOSH Guide to Industrial Respiratory Protection | last1=Bollinger | first1=Nancy J. | date=1987 }}</ref>
▲Escape breathing apparatus are a class of self contained atmosphere supplying or air purifying breathing apparatus for use in emergencies, intended to allow the user to pass through areas without a breathable atmosphere to a place of relative safety where the ambient air is safe to breathe. These are ambient pressure systems, and include:
▲*[[Helicopter escape set]]
▲*[[Mine escape set]]
▲*[[Submarine escape set]]
▲*[[Amphibious Tank Escape Apparatus]]
▲*[[Smoke hood]]
==Certification==▼
▲Early escape sets were often [[rebreather]]s and were typically used to escape from [[submarine]]s that were unable to surface. Escape sets are also used ashore, in the [[mining]] industry, and by the military for escape from tanks.
Escape respirators should be certified by a national authority analogous to the United States' [[National Institute for Occupational Safety and Health]] (NIOSH) for use in the atmosphere types for which the respirator is intended.<ref name="29 CFR 1910" /> Some standards apply to the level of protection for the user, and others relate to the intrinsic safety of the equipment for use in flammable and potentially explosive atmospheres. Some standards are voluntary, going above the minimum requirements of a national authority such as NIOSH.<ref>{{Cite web |last=Roy |first=Derek |date=April 1, 2020 |title=Selecting Self-Contained Breathing Apparatus for Industrial Plants |url=https://ohsonline.com/Articles/2020/04/01/Selecting-SelfContained-Breathing-Apparatus-for-Industrial-Plants.aspx?Page=1 |access-date=March 29, 2024 |website=OH&S Occupational Health and Safety |archive-date=March 29, 2024 |archive-url=https://web.archive.org/web/20240329132554/https://ohsonline.com/Articles/2020/04/01/Selecting-SelfContained-Breathing-Apparatus-for-Industrial-Plants.aspx?Page=1 |url-status=live }}</ref> Conformance with voluntary standards may be shown through third-party [[product certification]] such as those issued by the [[Safety Equipment Institute|Safety Equipment Institute (SEI)]].
Depending on the industry in which they are used, escape respirators may have to comply with, or be approved in terms of, one or more of:<ref name="MSA" />
*ASTM E2952-23 — Standard Specification for Air-Purifying Respiratory Protective Smoke Escape Devices (RPED)<ref name=":0" />
*NFPA 1981-19 — Standard on Open-Circuit Self-Contained Breathing Apparatus (SCBA) for Emergency Services<ref>{{Cite book |title=NFPA 1981 Standard on Open-Circuit Self-Contained Breathing Apparatus (SCBA) for Emergency Services |date=September 3, 2018 |publisher=National Fire Protection Association |year=2018 |isbn=978-145592088-4 |edition=2019 |location=Quincy, MA |publication-date=September 3, 2018 |language=English}}</ref>
*NFPA 1984-22 — Standard on Respirators for Wildland Fire-Fighting and Wildland Urban Interface Operations<ref>{{Cite book |title=NFPA 1984 Standard on Respirators for Wildland Fire-Fighting and Wildland Urban Interface Operations |date=April 8, 2021 |publisher=National Fire Protection Association |year=2021 |isbn=978-145592810-1 |edition=2022 |location=Quincy, MA |publication-date=April 8, 2021 |language=English}}</ref>
*NFPA 1986-23 — Standard on Respiratory Protection Equipment for Tactical and Technical Operations<ref>{{Cite book |title=NFPA 1986 Standard on Respiratory Protection Equipment for Tactical and Technical Operations |date=April 24, 2022 |publisher=National Fire Protection Association |year=2022 |isbn=978-145592947-4 |edition=2023 |location=Quincy, MA |publication-date=April 24, 2022 |language=English}}</ref>
*NFPA 1987-23 — Standard on Combination Unit Respirator Systems for Tactical and Technical Operations<ref>{{Cite book |title=NFPA 1987 Standard on Combination Unit Respirator Systems for Tactical and Technical Operations |date=April 24, 2022 |publisher=National Fire Protection Association |year=2022 |isbn=978-145592946-7 |edition=2023 |location=Quincy, MA |publication-date=April 24, 2022 |language=English}}</ref>
*EN 402:2003 — Respiratory protective devices - Lung governed demand Self-contained open-circuit compressed air breathing apparatus with full face mask or mouthpiece assembly for escape.<ref name="MSA" />
*ISO 23269-1:2008 — Ships and marine technology — Breathing apparatus for ships — Part 1: Emergency escape breathing devices (EEBD) for shipboard use.<ref name="Draeger" /><ref name="MSA" />
*ISO 23269-4:2011<ref name="Draeger" />
*EN 1127-1:2011 — Explosive atmospheres - Explosion prevention and protection - Part 1: Basic concepts and methodology
*EN1146:2005<ref name="Draeger" />
*EN 13463-1:2009 — Non-electrical equipment for use in potentially explosive atmospheres – Part 1: Basic method and requirements<ref name="MSA" />
*IEC/TS 60079-32-1:2013 — Explosive atmospheres – Part 32-1: Electrostatic hazards, guidance<ref name="MSA" />
*SOLAS Chapter II-2, the Marine Equipment Directive<ref name="Draeger" /> and the Pressure Equipment Directive.<ref name="Draeger" />
==History==
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*1939: [[Hans Hass]] developed from the escape set a type of rebreather with its bag on his back and two [[Breathing tube (in breathing apparatus)|breathing tube]]s but no backpack box. These sets appear much in his [[movie]]s and books.
===
Escape sets are used in these films:
*''[[Das Boot]]'' (Johann das Gespenst stops water from breaking in under a [[diesel engine]]).{{cn|date=August 2023}}
*''{{Interlanguage link multi|Haie und kleine Fische|de}}'' (controlled exit from a sunk submarine).{{cn|date=August 2023}}
*''[[In Enemy Hands (film)|In Enemy Hands]]'' (To survive a prolonged submersion while under attack by a destroyer){{cn|date=August 2023}}
▲|File:Immersion Suite.JPG|Russian submarine-escape suit including a [[rebreather]].
▲==Certification==
==See also==
* {{annotated link|Davis Submerged Escape Apparatus}}
* {{annotated link|Smoke hood}}
* {{annotated link|Submarine Escape Immersion Equipment}}
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{{reflist|refs=
<ref name="29 CFR 1910" >{{Cite web|title=29 CFR § 1910.134 - Respiratory protection.|url=https://www.law.cornell.edu/cfr/text/29/1910.134|access-date=2020-09-27|website=LII / Legal Information Institute|language=en|archive-date=2020-09-10|archive-url=https://web.archive.org/web/20200910151910/https://www.law.cornell.edu/cfr/text/29/1910.134|url-status=live}}</ref>
<ref name="ashsafety">{{cite web |url=https://www.ashsafety.com/tips/choosing-escape-sets.htm |title=Choosing Escape Breathing Apparatus |website=/www.ashsafety.com |publisher=Ash Safety |access-date=17 August 2023 }}</ref>▼
▲<ref name="ashsafety">{{cite web |url=https://www.ashsafety.com/tips/choosing-escape-sets.htm |title=Choosing Escape Breathing Apparatus |website=/www.ashsafety.com |publisher=Ash Safety |access-date=17 August 2023 |archive-date=17 August 2023 |archive-url=https://web.archive.org/web/20230817031509/https://www.ashsafety.com/tips/choosing-escape-sets.htm |url-status=live }}</ref>
<ref name="Draeger" >{{cite web |url=https://www.draeger.com/Products/Content/saver-cf-pi-9045407-en_1.pdf |title=Dräger Saver CF – Emergency Escape Breathing Apparatus (EEBA) |website=www.draeger.com |access-date=18 August 2023 }}</ref>
<ref name="MRS" >{{cite web |url=https://www.mrsl.co.uk/news/guide-escape-breathing-apparatus |title=A Guide to Escape Breathing Apparatus |date=27 July 2021 |website=www.mrsl.co.uk |access-date=17 August 2023 |archive-date=18 August 2023 |archive-url=https://web.archive.org/web/20230818182400/https://www.mrsl.co.uk/news/guide-escape-breathing-apparatus |url-status=live }}</ref>
<ref name="MSA" >{{cite web |url=https://gb.msasafety.com/breathingdevices-enews?locale=en |title=Emergency Escape Breathing Devices use in OGP applications |website=gb.msasafety.com |access-date=17 August 2023 |archive-date=25 September 2022 |archive-url=https://web.archive.org/web/20220925071829/https://gb.msasafety.com/breathingdevices-enews?locale=en |url-status=live }}</ref>
<ref name="NIOSH" >{{cite web |url=http://niosh.dnacih.com/nioshdbs/docs/2005-100/chapter4.html |title=NIOSH Respirator Selection Logic 2004, Chapter IV. Escape Respirators |date=October 2004 |work=NIOSH Publication No. 2005-100 |publisher=National Institute for Occupational Safety and Health |access-date=2023-08-18 |archive-date=2023-08-18 |archive-url=https://web.archive.org/web/20230818182358/http://niosh.dnacih.com/nioshdbs/docs/2005-100/chapter4.html |url-status=live }}</ref>
<ref name="safetygas">{{cite web |url=https://en.safetygas.com/respiratory-protection/eebd |title=Emergency escape breathing device EEBD |website=en.safetygas.com |access-date=17 August 2023 |archive-date=27 July 2023 |archive-url=https://web.archive.org/web/20230727060914/https://en.safetygas.com/respiratory-protection/eebd |url-status=live }}</ref>
}}
{{Breathing apparatus|
{{Authority control}}
{{DEFAULTSORT:Escape breathing apparatus}}
[[Category:
[[Category:Emergency equipment]]
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