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Encyclopedia > Dry Suit

A dry suit or drysuit provides thermal insulation to the wearer while immersed in water, and is worn by divers, boaters, water sports enthusiasts, and others who work or play in or near cold water. The drysuit protects the whole human body, except the head, hands, and possibly the feet. Drysuits are used typically in these cases: Thermal insulation on the Huygens probe The term thermal insulation can refer to materials used to reduce the rate of heat transfer, or the methods and processes used to reduce heat transfer. ... A diver is an person who practices scuba diving or surface supplied diving. ... // Boating, the leisurely activity of traveling by boat typically refers to the recreational use of boats whether power boats, sail boats, or yachts (large vessels), focused on the travel itself, as well as sports activities, such as fishing or waterskiing. ... A water sport is a form of recreation where water (other than drinking water) is an essential aspect of the activity. ...

  • where the water temperature is between -2 and 15°C (28 to 60°F).
  • for extended immersion in water below 15°C (60°F), where discomfort would be experienced by a wetsuit user.
  • with an integral helmet, boots, and gloves for personal protection when working in and around hazardous liquids.

The main difference between drysuits and wetsuits is that drysuits are designed to prevent water entering. This generally allows better insulation in drysuits making them more suitable for use in cold water. Drysuits can be uncomfortably hot in warm or hot air. A surfer in a wetsuit. ...

The neck seal, the zip, the inflator, a wrist seal, and the manual vent of a neoprene drysuit
The neck seal, the zip, the inflator, a wrist seal, and the manual vent of a neoprene drysuit

Contents

Image File history File linksMetadata Download high-resolution version (2592x1944, 1252 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Dry suit Metadata This file contains additional information, probably added from the digital camera or scanner used to... Image File history File linksMetadata Download high-resolution version (2592x1944, 1252 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Dry suit Metadata This file contains additional information, probably added from the digital camera or scanner used to... Neoprene is the DuPont Chemical trade name for a family of synthetic rubbers based on polychloroprene. ...

Parts of a dry suit

Needed

Shell

The main part of the drysuit is a waterproof shell, made from a membrane type material, neoprene foam rubber, or a hybrid of both. Neoprene is the DuPont Chemical trade name for a family of synthetic rubbers based on polychloroprene. ...


Membrane

Membrane drysuits are made from thin materials, and thus by themselves have little thermal insulation. They are commonly made of vulcanised rubber, or laminated layers of nylon, butyl rubber, and nylon. Membrane drysuits typically do not stretch, so they need to be made oversized and baggy to allow flexibility at the joints through the wearer's range of motion. This makes membrane drysuits easy to put on and get off, provides a great range of motion for the wearer, and makes them comfortable to wear for long periods, as the wearer does not have to pull against rubber elasticity. This article needs to be cleaned up to conform to a higher standard of quality. ... Nylon is a generic designation for a family of synthetic polymers first produced on February 28, 1935 by Wallace Carothers at DuPont. ... Butyl rubber is a synthetic rubber, a random copolymer of about 98% of isobutylene with about 2% of isoprene. ... Nylon is a generic designation for a family of synthetic polymers first produced on February 28, 1935 by Wallace Carothers at DuPont. ... Elasticity has meanings in two different fields: In physics and mechanical engineering, the theory of elasticity describes how a solid object moves and deforms in response to external stress. ...


To stay warm in a membrane suit, the wearer must wear an insulating undersuit, today typically made with polyester or other synthetic fiber batting. Polyester and other synthetics are preferred over natural materials, since synthetic materials have better insulating properties when damp or wet from sweat, seepage, or a leak. Categories: Move to Wiktionary | Stub | Diving ... SEM picture of a bend in a high surface area polyester fiber with a seven-lobed cross section Polyester is a category of polymers, or, more specifically condensation polymers, which contain the ester functional group in their main chain. ... Batting has several meanings: In baseball, batting is the act of attempting to hit the ball thrown by the pitcher, in order to score runs. ... SWEAT is an OLN/TSN show hosted by Julie Zwillich that aired in 2003-2004. ...


Reasonable care must be taken not to hole or tear membrane drysuits, because buoyancy and insulation depend completely on the gas pockets in the undersuit. The drysuit material offers essentially no buoyancy or insulation itself, so if the drysuit leaks or is torn, water can soak the undersuit, with a corresponding loss of buoyancy and insulation.


In warmer waters, some wearers wear specially designed membrane drysuits without an undersuit. These are different in design, materials, and construction from drysuits made for cold water diving.


Membrane drysuits may also be made of a waterproof and breathable material to enable comfortable wear when of the water for long periods of time. Sailors and boaters who intend to stay out of the water prefer this type of suit. Three types of sailor are seen here in the wheelhouse: a master, an able seaman, and a harbour pilot. ...


Neoprene

Neoprene is a closed cell foam synthetic rubber, containing millions of tiny air bubbles, forming a buoyant and thermally insulating material. If torn or punctured, a neoprene suit still keeps the insulation and buoyancy of the neoprene's bubbles when flooded. Being made of a fairly rigid dense material, they are more difficult to get on and off than membrane drysuits, and their buoyancy and thermal protection decreases with depth as the air bubbles in the neoprene are compressed, like with wetsuits. Neoprene also tends to shrink over the years as it outgases and slowly becomes more rigid. An alternative is crushed neoprene, which is less susceptible to volume changes when under pressure and shrinks less. Neoprene is the DuPont Chemical trade name for a family of synthetic rubbers based on polychloroprene. ... Sea foam on the beach. ... Synthetic rubber is any type of artificially made polymer material which acts as an elastomer. ...


Neoprene wetsuits fitted with neck, wrist, and ankle seals are also known as semi-dry suits, but the seals on these suits only reduce cold water seepage, so the inside of the suit still gets wet. Semi-dry suits are worn to keep the user warm while immersed in water temperatures generally between 10 and 20 °C (50 to 70 °F). ...


Hybrid

These combine the features of both types, with a membrane top attached to a neoprene bottom near the waist. The neoprene part is usually configured as a sleeveless "farmer-john" that covers the torso as well. This style is often used for surface water sports, especially in very cold water. The tight fitting lower part lets the wearer kick while swimming, and the loose fitting top allows easy arm movement. The torso covering also provides additional self-rescue or survival time if the suit leaks.


Seals

Seals at the wrists and neck prevent water entering the suit by compressing in a ring like a rubber band around the wrists and neck. The seals are not absolutely watertight, however, and the wearer may experience some seepage during use. The wearer will also get damp due to sweat and condensation. The seals are made from latex rubber or neoprene. Latex seals are supple but easily damaged and deteriorate with exposure to oils, oxygen, and other materials, so they must be replaced periodically, every two years or more. Neoprene seals last longer, but, being stiffer, let more water enter because they do not seal as effectively as latex seals to the contours of wrist and neck skin. They are also typically glued and sewn together to form a ring, and may leak along that seam. SWEAT is an OLN/TSN show hosted by Julie Zwillich that aired in 2003-2004. ... Water vapor condensing over a cup of hot tea Condensation is the change in matter of a substance to a denser phase, such as a gas (or vapor) to a liquid. ... The LaTeX logo, typeset with LaTeX LATEX, written as LaTeX in plain text, is a document markup language and document preparation system for the TeX typesetting program. ... Latex being collected from a tapped rubber tree Rubber is an elastic hydrocarbon polymer which occurs as a milky colloidal suspension (known as latex) in the sap of several varieties of plants. ... Neoprene is the DuPont Chemical trade name for a family of synthetic rubbers based on polychloroprene. ... General Name, Symbol, Number oxygen, O, 8 Chemical series nonmetals, chalcogens Group, Period, Block 16, 2, p Appearance colorless (gas) very pale blue (liquid) Standard atomic weight 15. ...


Waterproof Entry

Waterproof zipper installed on a membrane type dry suit
Waterproof zipper installed on a membrane type dry suit

Modern dry suits have a waterproof zipper for entry and exit which was originally developed by NASA to hold air inside astronaut space suits. The zipper is commonly installed across the back of the shoulders, but can also be found diagonally across the front of the torso, on the side, or straight down the middle of the front or back. Image File history File linksMetadata Size of this preview: 800 × 440 pixelsFull resolution (1024 × 563 pixel, file size: 145 KB, MIME type: image/jpeg) I took this picture. ... Image File history File linksMetadata Size of this preview: 800 × 440 pixelsFull resolution (1024 × 563 pixel, file size: 145 KB, MIME type: image/jpeg) I took this picture. ... Zipper slider brings together the two sides A zipper (British English: zip fastener or zip) is a popular device for temporarily joining two edges of fabric. ... The National Aeronautics and Space Administration (NASA) is an agency of the United States federal government, responsible for the nations public space program. ... Apollo 15 space suit A spacesuit is a complex system of garments, equipment, and environmental systems designed to keep a person alive and comfortable in the harsh environment of outer space. ...


There are many zipper arrangements in use because the zipper is very rigid, and cannot stretch at all, which can make it difficult for a user to get into and out of the suit. The zipper opening is often quite small, since a large zipper makes the suit stiffer and more difficult to use. Some complex zipper arrangements that wrap around the neck or chest let the suit swing open with a flap or hinge point.


Dry suits may also be fitted with an extra waterproof zipper "fly" to let the user urinate when the suit is worn for long periods. Some snug-fitting suits may also use wrap-around expansion zippers that allow the suit to expand or contract to fit different size people.


Before waterproof zips were invented, other methods had to be devised, with the most common being a long rubber entry tunnel which would be flattened shut, then rolled together from the sides and finally folded and clamped with a metal clip. An early example was the Sladen suit, where the entry tunnel was at the umbilicus. The Louisiana-based drysuit company [www.aquala.com/ Aquala] still makes a "historical" diving suit of that kind. The Sladen Suit was a heavy type of British divers drysuit made by Siebe Gorman. ... This article or section does not cite its references or sources. ...


Another type was a rubber tunnel that protruded through a normal cloth zipper. The tunnel would be rolled shut and the zipper closed to hold the roll in place. At least one make of old-type British frogman's drysuit was one-piece with a wide neck hole for entry; the bottom of the hood and the edge of the suit's neck hole were held together by a large circular steel clamp around the neck; there was a watertight seal in the bottom of the hood. Two-piece drysuit designs in full length for year-round use and "shorty" styles for summer-season use were also common in the 1950s and early 1960s. Two-piece suits of the period include the American-made Spearfisherman frogman suit, US Divers Seal Suit and the So Lo Marx Skooba Totes suit, the Italian-made Pirelli suit and the UK-made Heinke Delta suit and Siebe-Heinke Dip suit. These suits were sealed at the waist by rolling together the excess material at the bottom of the shirt and the top of the pants. A cummerbund, rail, or surgical tubing was sometimes provided to make the seal more waterproof. [www.customworks.co.uk/ Customworks] of Idaho manufactures a modern version of the two-piece drysuit. Though lacking such features as valves and zippers, these suits still have certain advantages over their modern counterparts. For example, they are cheaper, less bulky, more easily repaired and the footed pants could also double as fishing waders. // This page describes a type of scuba diver. ... Spearfisherman can mean:- Someone who spearfishes A company which made drysuits and swimfins (and perhaps other types of diving gear). ... US Divers is the Sporting Goods Division of Aqua Lung America, who make scuba diving equipment. ... Pirelli & C. SpA is a diverse multinational company based in Milan, Italy. ... Heinke (in full C.E. Heinke, submarine engineer and similar) was a diving gear making firm in London. ... Siebe may refer to:- Augustus Siebe: inventor of the standard diving dress. ... Heinke (in full C.E. Heinke, submarine engineer and similar) was a diving gear making firm in London. ... Orange cummerbund A cummerbund is a broad waist sash, usually pleated, which is often worn with black tie. ... This article or section does not cite its references or sources. ...


Optional

Thermal Undersuits

For cold-water use, especially diving under ice sheets, the user will usually wear a thick undersuit in a membrane dry suit. The thickness of undersuits varies and can be chosen by the wearer according the water temperature. Neoprene dry suits are made from a foam-rubber sheet containing tiny air bubbles, which provide insulation by themselves and generally eliminates the need for an undersuit. A neoprene wetsuit can also be worn under a membrane dry suit for extra protection against condensation and leaks.

The finger arrangement in a 3-finger drysuit mitt.
The finger arrangement in a 3-finger drysuit mitt.

Download high resolution version (800x800, 58 KB) Wikipedia does not have an article with this exact name. ... Download high resolution version (800x800, 58 KB) Wikipedia does not have an article with this exact name. ...

Gloves, Mitts, and 3-Finger Mitts

Drysuits may have wrist seals, permanently attached gloves/mitts, or a third option known as the attachment ring (described below).


If it is not important to have exposed bare hands, permanently attached heavy rubber gloves or mitts can help make getting in and out of the suit much easier since there is no need for the suit to tightly seal around the wrists. Instead, the wearer can slip into the attached gloves as if they were a loose-fitting coat sleeve.


Full-hand diving mitts can be sometimes useful in extreme environments such as ice diving.


Three-finger mitts are a midpoint between gloves and mittens. In the three-finger mitts, the fingers are arranged like the science-fiction Vulcan salute. This provides slightly better hand-grasping dexterity while still permitting heavy insulation around the hands. It has been suggested that Tplana-hath be merged into this article or section. ... Look up insulation in Wiktionary, the free dictionary. ...


Hoods

The drysuit may also have an integrated hood, which seals water out around the wearer's face, and helps keep the wearer's head warm. The integrated hood is often latex rubber that fits tightly around the head, but can also be made from neoprene or membrane to allow an insulating cap to be worn under the hood. Care must be taken to avoid the hood making a waterproof seal around either of the ears, as this would risk an eardrum bursting outwards at depth. Look up Hood in Wiktionary, the free dictionary. ... Barotrauma is physical damage to body tissues caused by a difference in pressure between an air space inside or beside the body and the surrounding gas or liquid. ...


Separate (non integral) neoprene hoods for use with a dry suit are different from wetsuit hoods, because they cannot be tucked inside the suit at the collar, as this would compromise the neck seal; with these the wearer's head gets wet, which would be a risk when diving in contaminated water.


Helmets

When a diver needs to be underwater for long periods of time day after day, a snug-fitting elastic hood can cause uncomfortable pressure sores on the ears, face, and jaw. To alleviate this and to permit easy surface communication, a hard metal or plastic diving helmet may be worn with the drysuit. This can be separate from the drysuit with its own watertight neck seal, or it can be permanently attached with a neck ring, and air from the helmet can enter into the suit. Bedsores, also called pressure sores or decubitus ulcers, are ulcers (sores) caused by prolonged pressure or rubbing on vulnerable areas of the body. ... Diving helmets are worn by divers who need to speak and hear underwater. ...


Boots

Most commercial diving dry suits have heavy built-in boots. Sport diving suits may have boots or thin sheet-rubber booties. Surface dry suits may have booties or ankle seals to allow better foot control of water skis and [[surfboard]s. Surface dry suits may be used with separate non-waterproof neoprene booties for foot warmth, and aqua-shoes for protection while using personal watercraft. Bootie is a slang term for a musical bootleg, which is also popularly known as a mash-up or bastard pop. ... Recreational skiiers typically use two skis — other techniques abound. ... Categories: Stub ...


For a commercial environment where the option of interchangeable boots for different sizes of feet is desired, the legs of the dry suit can also be fitted with attachment rings (described below).


Weight boots

For commercial drysuit divers who must work on the sea bottom or on an underwater platform (such as under an oil rig), the drysuit may be fitted with heavy metal boots to keep the diver firmly weighted down. This allows the suit to be comfortably inflated like a balloon as the diver works, without concern that the diver may float uncontrollably to the surface. These divers cannot swim freely, and may need to ride an underwater cable elevator down to the work area. Natural gas drilling rig A drilling rig or oil rig is a structure housing equipment used to drill for and extract oil or natural gas from underground reservoirs. ... It has been suggested that this article or section be merged with Elevator surfing. ...


Attachment rings

These are typically only seen on professional and commercial diving suits. They allow separate neck seals, gloves, and boots to be joined to the suit with a watertight seal. The attachment ring system uses a support ring inside the suit and a clamping band outside the suit to tightly hold the suit and the separate hood/boot/glove together. They were also used with the neck seals of some old British frogman-type drysuits: see above.


The support ring can optionally be slipped into the sleeve of a regular drysuit that has wrist seals, to temporarily put watertight rubber gloves on the suit, or the wrist seals can be removed and the inner support ring is permanently attached inside the sleeve. The support ring may be a large one-piece unit that can be slipped over the head/hands/feet, or it may be split into halves that can be directly installed up close around the neck/wrists/ankles.


Attachment rings let a commercial diver change his suit to best perform the task at hand. Wrist seals can still be used with an attachment ring suit; they are mounted onto the ring like a pair of gloves.


Valves

A typical diving drysuit has an air exhaust valve, which lets the diver vent gas from the suit during the ascent. This is necessary because when the diver ascends, the air in the suit expands, balloons out the suit, and hinders movement. The air in a ballooned suit can overcome the diver's neutral buoyancy, and can cause a sudden uncontrolled ascent to the surface, resulting in decompression sickness and loss of consciousness if the diver does not immediately descend and undergo controlled decompression. Decompression sickness (DCS), the diver’s disease, the bends, or caisson disease is the name given to a variety of symptoms suffered by a person exposed to a reduction in the pressure surrounding their body. ... Decompression sickness (DCS), the diver’s disease, the bends, or caisson disease is the name given to a variety of symptoms suffered by a person exposed to a reduction in the pressure surrounding their body. ...


Vent valves can be automatic, operating as pressure relief valves, or manual, where the diver must raise the valve to vent. Automatic vents are generally at the shoulder, and manual vents are at the wrist. Some older drysuits have no vents, but the diver must lift one of the wrist seals or the neck seal open to vent the drysuit. Surface dry suits are not inflated, and must be vented to remove most of the gas inside.


Because the air inside the suit is compressed as the diver descends, a modern diving drysuit also has a gas inflation valve, which lets the diver control the buoyancy of the suit by injecting gas from a diving cylinder to avoid the suit from being squeezed tightly and painfully onto the diver's body during descent. The sensation is similar to being pinched, but all over the body. Suit squeeze can also hinder the diver's movement and make swimming more difficult. 12 litre and 3 litre steel diving cylinders A diving cylinder or SCUBA tank is used to store and transport high pressure breathing gas as a component of an Aqua-Lung. ...


Some old-type frogman's drysuits had a small "jack cylinder" to be inflated from, or the frogman (who was using an oxygen rebreather and so limited to about 30 feet (9.144 m) depth) had to put up with the suit squeeze. // This page describes a type of scuba diver. ... A rebreather is a type of breathing set that provides a breathing gas containing oxygen and recycles exhaled gas. ...


Normally, the gas used for dry suit inflation for diving is air from the primary breathing cylinder. When divers breathe helium-based gas mixes such as trimix, they often avoid inflating their suits with the helium-based gas due to its high thermal conductivity. They often carry a separate cylinder for this purpose; generally it contains air, although sometimes argon, which has lower thermal conductivity, is used. Pure argon cannot be used as a breathing gas. Alternatively, some trimix divers inflate their suits from a decompression cylinder containing a nitrox blend. General Name, Symbol, Number helium, He, 2 Chemical series noble gases Group, Period, Block 18, 1, s Appearance colorless Standard atomic weight 4. ... Air is the most common and only natural breathing gas. ... Trimix is a breathing gas, consisting of oxygen, helium and nitrogen, and is often used during the deep phase of dives carried out using Technical diving techniques. ... In physics, thermal conductivity, k, is the intensive property of a material that indicates its ability to conduct heat. ... General Name, Symbol, Number argon, Ar, 18 Chemical series noble gases Group, Period, Block 18, 3, p Appearance colorless Atomic mass 39. ... Air is the most common and only natural breathing gas. ... A Decompression Stop is a period of time a diver must spend at a constant depth in shallow water at the end of a dive in order safely to eliminate inert gases from the divers body to avoid decompression sickness. ...


In surface dry suits, the wearer normally never dives deeply underwater, and is not concerned about neutral buoyancy, so there are no air valves on a surface drysuit.


The P-Valve

For commercial divers or technical divers who may spend many hours in a drysuit underwater, it is not practical to have to climb back onboard the ship in order to open a waterproof relief zipper and urinate. The P-valve is a urinal built into the suit, which lets a male diver relieve himself at any time without having to get out of the water, and keeping him dry and clean inside the suit.


Before putting on the drysuit, the diver puts on a condom catheter, which is similar to a condom except that it is made of thicker material with a cuff or adhesive ring to prevent it from slipping off, and its end connects to a built-on drain tube. After putting it on, he attaches the end of the tube to a drain hose in the crotch of the suit. This drain hose leads to a vent opening just above a knee, and may also have a one-way valve (P-valve)to prevent ocean water from flowing back in if the hose gets disconnected. A condom is a device, usually made of latex, or more recently polyurethane, that is used during sexual intercourse. ...


Female divers intending to urinate in drysuits sometimes wear an adult diaper / nappy, which soaks up and retains the urine. Nappy directs here. ... Nappy can refer to one of the following: a popular adjective describing Afro textured hair a diaper This is a disambiguation page: a list of articles associated with the same title. ...


Uses of dry suits

Surface

Boating

Dry suits are often worn for boating, especially sailing, and with personal water craft in the winter months. The primary uses are for protection from spray, and in case of accidental short-term immersion in cold water if the user falls overboard. Dry suits only intended for temporary immersion protection are less rugged than diving dry suits. They are usually made of a breathable membrane material to let sweat permeate, keeping the wearer dry and comfortable all day. Membrane type surface dry suits only keep the user dry, and have little thermal insulating properties. Most users will wear a thin thermal undersuit, or street clothes, for warmth; but wearing ordinary fabrics can be dangerous if the suit leaks in cold water because they will lose all insulating properties. // Boating, the leisurely activity of traveling by boat typically refers to the recreational use of boats whether power boats, sail boats, or yachts (large vessels), focused on the travel itself, as well as sports activities, such as fishing or waterskiing. ... For either of the songs named Sailing, see Sailing (song). ... Pump-jet PWCs such as this Yamaha Waverunner are extremely popular for their speed and maneuverability. ... An artificial membrane, also called a synthetic membrane, is a membrane prepared for separation tasks in laboratory and industry. ... Categories: Move to Wiktionary | Stub | Diving ...


Water Sports

Kitesurfers wearing dry suits on Long Island in winter when the air and water temperatures are near 32 ºF (0 °C).
Kitesurfers wearing dry suits on Long Island in winter when the air and water temperatures are near 32 ºF (0 °C).

Dry suits are used for windsurfing, kitesurfing, water skiing and other surface water sports where the user is frequently immersed in cold water. These suits are often made from very lightweight material for high flexibility. Membrane type suits are commonly used in the spring and fall with moderate water temperatures, but Neoprene and hybrid dry suits for surface sports are preferred in cold water. These provide greater thermal protection in the event of a leak. The ability to swim for self-rescue in these types of suits is important to water sports users that do not use a boat. A neoprene bottom also is less likely to allow trapped air to collect in the legs, causing the wearer to tend to float head down in the water. Image File history File links DrySuits. ... Image File history File links DrySuits. ... Kitesurfers use inflatable kites tethered to harnesses to glide through water and air Kitesurfing, also known as kite surfing, fly surfing, and kiteboarding, involves using a power kite to pull the rider through the water on a small surfboard, a wakeboard, or a kiteboard. ... Map showing Long Island; to the north is Connecticut and to the west are New York City and New Jersey. ... A windsurfer with modern gear tilts the rig and carves the board to perform a planing gybe (downwind turn) close to shore in Maui, Hawaii, one of the popular destinations for windsurfing. ... Kitesurfers use inflatable kites tethered to harnesses to glide through water and air Kitesurfing, also known as kite surfing, fly surfing, and kiteboarding, involves using a power kite to pull the rider through the water on a small surfboard, a wakeboard, or a kiteboard. ... Slalom Water Skiing // Water skiing is a surface water sport and recreational activity. ...


Working

Crew members who must work on the decks of commercial ships wear a type of dry suit also known as an immersion survival work suit. Single engine aircraft ferry pilots flying between North America and Europe, and helicopter pilots that must fly over the open ocean, must wear a survival suit in the cockpit, so they can continue to fly the aircraft, then exit immediately if the aircraft is ditched in cold water after an engine failure. These suits are also used on shore when working on docks, bridges, or other areas where cold water immersion is a safety risk. They are usually a three-part system consisting of: An immersion suit or, more specifically an immersion survival work suit, is a type of dry suit designed to keep water away from the skin, and prevent hypothermia, if its wearer falls into cold water. ...

  • A warm undersuit made of synthetic fabric designed to wick moisture from sweat generated by physical exertion away from the user’s skin.
  • A dry suit made with a waterproof breathable membrane to let moisture permeate out of the suit.
  • A durable outer shell, designed to protect the dry suit, and to carry tools and survival gear. The outer shell may also be equipped with an inflatable bladder to give the wearer additional flotation and freeboard when immersed.

Survival

Immersion survival suits are dry suits carried for use by ship and aircraft crew who will be immersed in cold water if the craft must be abandoned. Unlike immersion survival work suits, these are not intended to be worn all the time, and are only to be used in an emergency. Survival suits will typically be a one-piece design made of fire-retardant neoprene, and optimized with quick donning features. // A survival suit, or more specifically an immersion survival suit, is a special type of waterproof dry suit that protects the wearer from hypothermia from immersion in cold water, after abandoning a sinking or capsized vessel, especially in the open ocean. ...


Rescue

Dry suits are also worn by rescue personnel who must enter, or may accidentally enter, cold water. Features of dry suits designed for rescue may be a hybrid of the immersion survival and work suits, since the wearer is not expected to be working in the suit for an extended time. They may also be optimized for a specific task such as ice rescue, or helicopter rescue swimmer.


Underwater

Sport diving

These drysuits are made in both membrane and neoprene, and primarily differ from surface drysuits in that they have inflation and deflation air valves to maintain neutral buoyancy, and are slightly more durable. An artificial membrane, also called a synthetic membrane, is a membrane prepared for separation tasks in laboratory and industry. ... Neoprene is the DuPont Chemical trade name for a family of synthetic rubbers based on polychloroprene. ...


Commercial/military diving

These tend to be much heavier and even more durable than sport drysuits because they will endure a harsh and abrasive environment, especially if being used for heavy labor work such as underwater welding. Some commercial drysuits are rated for hazardous-environment diving, and when combined with a full-face helmet can completely isolate and protect the diver from hazardous environments such as sewage pits and chemical storage tanks. Diving helmets are worn by divers who need to speak and hear underwater. ...


Drysuit donning and diving hazards

Drysuits pose their own unique problems compared to wetsuit diving, due to the complex construction and since a diver needs to constantly manage and adjust the air volume inside the suit. During descent, air must be added to maintain constant volume. This prevents suit squeeze, loss of neutral buoyancy, and potential uncontrolled descent. During ascent, air must be removed to prevent ballooning, loss of neutral buoyancy, and potential uncontrolled ascent. A drysuit can be equipped with an automatic spring-loaded exhaust valve, which can assist with this problem.


Seal damage

Latex seals are easily pierced by sharp objects. Gripping the seal with long fingernails to pull it on or off can cut through the material, while long toenails can damage thin rubber booties when the foot is pushed inside tight-fitting fins.


Some types of latex seals may be liable to rubber perishing.


Latex seals are somewhat elastic, but can be easily torn if overstretched. Powdered talc can help the seals slide on easier. Talc (derived from the Persian via Arabic talq) is a mineral composed of hydrated magnesium silicate with the chemical formula H2Mg3(SiO3)4 or Mg3Si4O10(OH)2. ...


Zipper damage

Waterproof zippers need the two rows of open teeth to be reasonably lined up in front of the pull, for the zipper to slide easily. It is best to hold the opening together as the zipper is pulled shut to prevent misalignment that can permanently damage the sealing edge. For this reason zippers across the back of the shoulders or down the back of the suit are almost impossible for one person to close properly by themselves, and yanking harder to try and force the unreachable zipper closed often just results in misalignment and permanent zipper damage.


Suit damage

Damage to the lower part of the suit can cause a sudden inrush of very cold water for winter users, or an inrush of hazardous chemicals for commercial inspection divers.


Damage to the upper part of the suit can cause a sudden venting of the air, resulting in a total loss of thermal insulation in membrane suits and sudden uncontrolled descent, followed by water/chemicals seeping in.


Diving without a BCD

Since the drysuit can contain air, some divers control their buoyancy with the drysuit and dive without the usual BCD / buoyancy control vest that is commonly worn by wetsuit divers. Although it is possible to dive like this, the risks are higher than when using a buoyancy compensator, Drysuits generally are more easily damaged and prone to failure. Buoyancy compensators generally are more robust and reliable. A buoyancy compensator (or buoyancy control device, BC or BCD) is a piece of diving equipment worn by divers to provide: life saving emergency buoyancy both underwater and on the surface. ... A surfer in a wetsuit. ...


Inversion Hazards

Underwater

If there is more air in the drysuit than is needed to counteract “squeeze” on the undersuit, that excess air creates a "bubble" which moves to the highest point of the suit, which in an upright wearer is the shoulders.


Drysuit wearers wearing loose baggy suits need to keep their legs at level or below their waist. When inverted, with the legs above the waist, the bubble quickly moves top the highest point, the legs.


If the suit is being used correctly, the bubble is small and its movement is not important. The bubble may be large if a diver has ascended without venting the suit or the diver is over-weighted and extra air has been put in the suit to make the diver neutrally buoyant. The movement of a large bubble can be a problem; it balloons the legs and it may inflate the thin rubber booties causing the fins to pop off, losing them in the water. Also, as the drysuit vents are most often situated at the top half of the diver, it is impossible to vent the suit while inverted. If the diver is positively buoyant, there is an increased risk of a fast ascent to the surface.


The size of the bubble can be minimised by being correctly weighted and venting the suit on ascent. Some divers ensure that the bubble remains at the top of their body by using the buoyancy compensator to counteract any excess weighting and keeping the minimum air, to avoid squeeze, in the suit.


For an inexperienced diver, ballooning of the legs can cause a loss of control that may to lead to panic and an inability to flip upright again. The solution is not difficult: bend the knees, reach up and grab the legs, do a somersault to flip upright again and vent the suit if needed by opening the neck seal.


Surface

Surface drysuit users can face a similar inversion problem. The problem is more acute when not wearing a personal flotation device (life vest) over the drysuit. For surface drysuit users, the inversion situation can be much more critical if no one is nearby to assist, since the wearer may be held upside down and unable to breathe, and may also have water run down into their nose while inverted.


It is not a problem for close-fitting neoprene suits, or hybrid suits with neoprene bottoms, which prevent air from easily moving into the legs of the suit. Wearers of baggy surface drysuits can mitigate the problem by venting out as much excess air as possible before entering the water. This is typically done by crouching down and leaning forward, wrapping the arms around the knees, and then having an assistant zip the suit shut while it is stretched out tightly. Excess air can also be "burped" out of the neck seal. Some baggy suits have elastic "gaiters" that can be pulled snug around the legs to help prevent this inversion event from happening. Gaiters are a type of protective clothing for a persons ankles and legs below the knee. ...


Early examples of drysuits

These suits are all the membrane type.

Maker Make 1/2 piece? When available Notes Info link
Pirelli Pirelli Diving Suit 2 from 1930's designed for Italian frogmen [1]
Siebe Gorman "Frogman" suits 1 or 2 WWII & after designed for British frogmen
rubberized stockinette
Spearfisherman Spearfisherman Frogman Suits 2 1945 & after designed for USA frogmen [2]
US Divers US Divers Seal Suit 1 or 2 from 1953 or before varIous [3]
Heinke Heinke Delta Suit 2 from mid-1950's rubberized stockinette [4]
Healthways Healthways Carib Suits 2 from 1955 or before pure natural rubber [5]
Bel-Aqua[1] Bel-Aqua Dry Suits 1
2
from 1955 or before a 3-ply material, front tube entry
a 3-ply material
[6]
unidentified Seamless Suits 2 from 1953? dipped pure latex [7]
made by or for Lillywhites Lillywhites Mid-1950s Suits 2 from 1955 or earlier rubberized stockinette [8]
So-Lo Marx Rubber Company Skooba-"totes" Suits 2 from early 1960's all-rubber [9]
Siebe Gorman Siebe-Heinke Dip Suit 2 1964 & after dipped latex [10]

Pirelli & C. SpA is a diverse multinational company based in Milan, Italy. ... // This page describes a type of scuba diver. ... Siebe Gorman Ltd was a British company which developed diving equipment and breathing equipment and worked on commercial diving and underwater salvage projects. ... German soldiers at the Battle of Stalingrad World War II was the most extensive and costly armed conflict in the history of the world, involving the great majority of the worlds nations, being fought simultaneously in several major theatres, and costing tens of millions of lives. ... // This page describes a type of scuba diver. ... Spearfisherman can mean:- Someone who spearfishes A company which made drysuits and swimfins (and perhaps other types of diving gear). ... // This page describes a type of scuba diver. ... US Divers is the Sporting Goods Division of Aqua Lung America, who make scuba diving equipment. ... Heinke (in full C.E. Heinke, submarine engineer and similar) was a diving gear making firm in London. ... Healthways was a firm which made scuba gear. ... Lillywhites in Piccadilly Circus. ... Siebe Gorman Ltd was a British company which developed diving equipment and breathing equipment and worked on commercial diving and underwater salvage projects. ...

References

  1. ^ designed by Bill Barada for Bel Aqua Water Sports Company, 3720 West 54th Street, Los Angeles. Bel-Aqua’s successor is Aquala Sports Manufacturing Company

See also


  Results from FactBites:
 
PADI Dry Suit Diver (221 words)
But, you want to be trained in proper techniques and this is where PADI Dry Suit Diver Specialty course comes in.
During your PADI Dry Suit Diver Specialty course, you'll not only cover the background knowledge related to dry suit diving, you'll get into confined water to put that theory into practice.
Your Adventures In Diving Dry Suit Adventure Dive may be count toward the Specialty course at instructor discretion.
common drysuit myths (3510 words)
Dry suits, on the other hand, allow the user to vary the amount of insulation required and give greater leeway for changes in body mass.
The downside of wearing a wet suit is that because the gas filled cells compress with depth a diver will, regardless of material thickness, begin to lose core body heat four times more rapidly than if they were wearing a dry suit together with the appropriate amount of underclothing.
Dry suits are again back in vogue as divers begin to appreciate both the economic as well as the practical advantages that this type of diving dress offers.
  More results at FactBites »

 
 

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