Escape set
Encyclopedia
An escape set is a breathing set, which lets its wearer survive for a time in an environment without (sufficiently) breathable air, in particular underwater, primarily or originally intending mainly to survive long enough to reach safety where the air is breathable.
The escape set was developed from such respirators and used to escape from a submarine submerged so long that its onboard air supply ran out, and for technical or military reasons the submarine could not surface: one example is the Davis Submerged Escape Apparatus
Davis Submerged Escape Apparatus
The Davis Submerged Escape Apparatus , was an early type of oxygen rebreather invented in 1910 by Sir Robert Davis, head of Siebe Gorman and Co. Ltd., inspired by the earlier Fleuss system...
. Escape sets were also used ashore, e.g. in the mining
Mining
Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...
industry.
Naming
In language nowadays in GermanGerman language
German is a West Germanic language, related to and classified alongside English and Dutch. With an estimated 90 – 98 million native speakers, German is one of the world's major languages and is the most widely-spoken first language in the European Union....
as in English
English language
English is a West Germanic language that arose in the Anglo-Saxon kingdoms of England and spread into what was to become south-east Scotland under the influence of the Anglian medieval kingdom of Northumbria...
, tauchen = "diving
Diving
Diving is the sport of jumping or falling into water from a platform or springboard, sometimes while performing acrobatics. Diving is an internationally-recognized sport that is part of the Olympic Games. In addition, unstructured and non-competitive diving is a recreational pastime.Diving is one...
" only means in water. Until the middle of the 20th century the German
German language
German is a West Germanic language, related to and classified alongside English and Dutch. With an estimated 90 – 98 million native speakers, German is one of the world's major languages and is the most widely-spoken first language in the European Union....
word tauchen = "to dive" also meant "to stay in unbreathable atmosphere". Thus around 1900 a water-cooled fire protection hood with air supply for firefighter
Firefighter
Firefighters are rescuers extensively trained primarily to put out hazardous fires that threaten civilian populations and property, to rescue people from car incidents, collapsed and burning buildings and other such situations...
s was called in German a Feuertaucher (= "fire diver"), and still into the 1940s in German a man with a breathing apparatus for use in unbreathable atmosphere was called a Gastaucher (= "gas diver"). But as escape sets were used more for rescue from sunken submarine
Submarine
A submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has more limited underwater capability...
s and as light diving equipment
Scuba set
A scuba set is an independent breathing set that provides a scuba diver with the breathing gas necessary to breathe underwater during scuba diving. It is much used for sport diving and some sorts of work diving....
, the German word "tauchen" was restricted to underwater meanings.
Chemical
Normal breathing air contains about 20% oxygenOxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
. In normal breathing the body uses about 4% and replaces it with carbon dioxide
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
. A certain volume of air can be "breathed deeply" several times, until its oxygen portion is exhausted. However, each breath becomes heavier, since carbon dioxide accumulates and oxygen is used up. Therefore this accumulating carbon dioxide must be removed from the breathing cycle.
For the general function of this sort of breathing set, see rebreather
Rebreather
A rebreather is a type of breathing set that provides a breathing gas containing oxygen and recycled exhaled gas. This recycling reduces the volume of breathing gas used, making a rebreather lighter and more compact than an open-circuit breathing set for the same duration in environments where...
.
The absorbent used is nearly always sodalime, or a material based on sodalime, but in former times slaked lime or quicklime or caustic soda was sometimes used.
Submarine escape sets had a mouthpiece, so the user had to also wear a noseclip
Noseclip
A noseclip is a small bent piece of wire covered in rubber worn by some swimmers . It is designed to clasp the nostrils closed to prevent water from getting in or air from escaping during activities such as synchronized swimming...
to avoid breathing water through his nose. The working time of an escape set depended upon depth of submersion, between 15 and 45 minutes.
Use during submarine rescue
If an emergency made exit from a submarine necessary, first the crew had to wait until the air inside the submarine was compressed by pressure of entering sea water until the remaining air pocket was at the same pressure as outside. The lower end of the escape hatch had therefore to be low enough so that the remaining air inside the submarine could not escape when the hatch was opened. Then the crew could step out. The set's user had to breathe continually to avoid pulmonary barotrauma. Escape sets are used in these films:-- Das BootDas BootDas Boot is a 1981 German epic war film written and directed by Wolfgang Petersen, produced by Günter Rohrbach, and starring Jürgen Prochnow, Herbert Grönemeyer, and Klaus Wennemann...
(Johann das Gespenst stops water from breaking in under a diesel engineDiesel engineA diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...
). - Haie und kleine Fische (controlled exit from a sunk submarine).
History
Development of the first militarily useful submarineSubmarine
A submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has more limited underwater capability...
s before the First World War raised briefly the question about rescue possibilities if the submarine sank. First, often deadly attempts
Hypoxia (medical)
Hypoxia, or hypoxiation, is a pathological condition in which the body as a whole or a region of the body is deprived of adequate oxygen supply. Variations in arterial oxygen concentrations can be part of the normal physiology, for example, during strenuous physical exercise...
were started with simple "breathing bags", which were useful as a very short-period assistance, but often did not contain enough oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
to survive the whole ascent. Robert Henry Davis and Henry A. Fleuss developed a rebreather
Rebreather
A rebreather is a type of breathing set that provides a breathing gas containing oxygen and recycled exhaled gas. This recycling reduces the volume of breathing gas used, making a rebreather lighter and more compact than an open-circuit breathing set for the same duration in environments where...
, which was useful in the mining
Mining
Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...
industry and under water.
- 1903: Siebe GormanSiebe GormanSiebe Gorman & Company Ltd was a British company which developed diving equipment and breathing equipment and worked on commercial diving and marine salvage projects...
started to make this breathing set in England; in the years afterwards it was improved, and later was called the Davis Submerged Escape ApparatusDavis Submerged Escape ApparatusThe Davis Submerged Escape Apparatus , was an early type of oxygen rebreather invented in 1910 by Sir Robert Davis, head of Siebe Gorman and Co. Ltd., inspired by the earlier Fleuss system...
. - 1905: An important innovation: metering valves to control the supply of oxygen. This was promptly adopted by other companies which made escape sets.
- 1907: Draeger of LübeckLübeckThe Hanseatic City of Lübeck is the second-largest city in Schleswig-Holstein, in northern Germany, and one of the major ports of Germany. It was for several centuries the "capital" of the Hanseatic League and, because of its Brick Gothic architectural heritage, is listed by UNESCO as a World...
invented the U-Boot-Retter = "submarine rescuer".
- Both systems were based on oxygen supply from a high-pressure cylinder with simultaneous absorption of carbon dioxideCarbon dioxideCarbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
by an inserted cartridge filled with sodium hydroxide.- 1916: The Draeger model DM 2 became standard equipment of the German NavyGerman NavyThe German Navy is the navy of Germany and is part of the unified Bundeswehr .The German Navy traces its roots back to the Imperial Fleet of the revolutionary era of 1848 – 52 and more directly to the Prussian Navy, which later evolved into the Northern German Federal Navy...
. - 1926: Draeger displayed a rescue breathing apparatus that the wearer could swim with. While the previous devices served only for ascending to the surface and were designed also to develop lift so that the wearer arrived at the surface without swimming movements, the diving set had weights, which also made it possible to dive downScuba divingScuba diving is a form of underwater diving in which a diver uses a scuba set to breathe underwater....
with it, to search and rescueSearch and rescueSearch and rescue is the search for and provision of aid to people who are in distress or imminent danger.The general field of search and rescue includes many specialty sub-fields, mostly based upon terrain considerations...
after an accident. - 1939: Hans HassHans HassHans Hass is a diving pioneer known mainly for his documentaries about sharks, the energon theory, and his commitment, later in life, to the protection of the environment. He was born in Vienna, Austria.-Early years:...
developed from the escape set a type of rebreather with its bag on his back and two breathing tubeBreathing tube (in breathing apparatus)A breathing tube is a flexible tube for breathing through, as part of a scuba set or other breathing apparatus or a medical oxygen apparatus or anaesthetic apparatus They are wide, and usually corrugated to let the user's head move about without the tube pinching at...
s but no backpack box. These sets appear much in his movies and books.
- 1916: The Draeger model DM 2 became standard equipment of the German Navy
Further developments of the escape gear
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
or compressed air
Compressed air
Compressed air is air which is kept under a certain pressure, usually greater than that of the atmosphere. In Europe, 10 percent of all electricity used by industry is used to produce compressed air, amounting to 80 terawatt hours consumption per year....
cylinder, which makes possible deeper use possible of these diving breathing sets.
Oxygen rebreathers are technically simpler than mixture breathing sets, but limits use to shallow water. Oxygen cycle devices are much liked by combat divers
Frogman
A frogman is someone who is trained to scuba diving or swim underwater in a military capacity which can include combat. Such personnel are also known by the more formal names of combat diver or combatant diver or combat swimmer....
and underwater photographers, as they make far fewer bubbles than aqualung
Aqua-lung
Aqua-Lung was the original name of the first open-circuit free-swimming underwater breathing set in reaching worldwide popularity and commercial success...
-type (open circuit) sets, and those bubbles could betray the diver.
Another operational area is fire protection, for instance in chemical industry
Chemical industry
The chemical industry comprises the companies that produce industrial chemicals. Central to the modern world economy, it converts raw materials into more than 70,000 different products.-Products:...
or rescue in the mining
Mining
Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...
industry, where need for a long use duration forbids use of compressed air sets. Advancements in rebreather
Rebreather
A rebreather is a type of breathing set that provides a breathing gas containing oxygen and recycled exhaled gas. This recycling reduces the volume of breathing gas used, making a rebreather lighter and more compact than an open-circuit breathing set for the same duration in environments where...
design include special more-or-less complex gas proportioning and control devices, allowing use even deeper and even longer, for work divers, than emergency breathing sets and the type of sport diving called technical diving
Technical diving
Technical diving is a form of scuba diving that exceeds the scope of recreational diving...
. Today's escape sets are combined with lifejacket
Lifejacket
A lifejacket is a type of personal flotation device designed to keep your airway clear of the water whether the wearer is conscious or unconscious...
s and protection hoods to protect the head and breathing organs from being overpowered by water. They are used with thermal protection suits similar to the well-known scuba diving
Scuba diving
Scuba diving is a form of underwater diving in which a diver uses a scuba set to breathe underwater....
drysuits. Use is nevertheless limited to comparatively small depths; escape capsules and rescue submarines and emergency lift devices and droppable ballast provide safety in deper water.
The original German model of escape set from the Second World War is still used now in Leopard 2
Leopard 2
The Leopard 2 is a main battle tank developed by Krauss-Maffei in the early 1970s for the West German Army. The tank first entered service in 1979 and succeeded the earlier Leopard 1 as the main battle tank of the German Army. Various versions have served in the armed forces of Germany and twelve...
tanks, as emergency safety devices in operations submerged in river
River
A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...
s.
A (very) special form of escape set is the (standard) escape capsule of the Space Shuttle
Space Shuttle
The Space Shuttle was a manned orbital rocket and spacecraft system operated by NASA on 135 missions from 1981 to 2011. The system combined rocket launch, orbital spacecraft, and re-entry spaceplane with modular add-ons...
. It is a spherical textile covering holding internal pressure and isolating an astronaut
Astronaut
An astronaut or cosmonaut is a person trained by a human spaceflight program to command, pilot, or serve as a crew member of a spacecraft....
, equipped with an escape set very similar to an underwater escape set, and can be carried by another astronaut (who is in a spacesuit) to a suitable rescue spacecraft.
Literature
- Hermann Stelzner, Tauchertechnik - Handbuch für Taucher / Lehrbuch für Taucheranwärter. Verlag Charles Coleman, LübeckLübeckThe Hanseatic City of Lübeck is the second-largest city in Schleswig-Holstein, in northern Germany, and one of the major ports of Germany. It was for several centuries the "capital" of the Hanseatic League and, because of its Brick Gothic architectural heritage, is listed by UNESCO as a World...
1943