Diving equipment, or underwater diving equipment, is equipment used by underwater divers to make diving activities possible, easier, safer and/or more comfortable. This may be equipment primarily intended for this purpose, or equipment intended for other purposes which is found to be suitable for diving use.
Diving equipment
Surface supplied commercial diving equipment on display at a trade show
Other names
Dive gear
Uses
Facilitate underwater diving operations
The fundamental item of diving equipment used by divers other than freedivers, is underwater breathing apparatus, such as scuba equipment, and surface-supplied diving equipment, but there are other important items of equipment that make diving safer, more convenient or more efficient. Diving equipment used by recreational scuba divers, also known as scuba gear, is mostly personal equipment carried by the diver, but professional divers, particularly when operating in the surface supplied or saturation mode, use a large amount of support equipment not carried by the diver.
Equipment which is used for underwater work or other activities which is not directly related to the activity of diving, or which has not been designed or modified specifically for underwater use by divers is not considered to be diving equipment.
Surface oriented surface-supplied diving (Bounce diving), where the diver starts and finishes the dive at normal atmospheric pressure.[1]
Standard diving dress - mostly used in professional diving. Usually free-flow open circuit air, but occasionally semi-closed circuit mixed gas. Mainly of historical interest now.
Surface-supplied open circuit free-flow air diving, using compressed atmospheric air as the breathing gas.
Surface-supplied mixed gas diving, using helium based, nitrox, or trimix breathing gases. Usually using lightweight demand helmets, sometimes with helium reclaim systems.
Freediving or breathhold diving, where the diver completes the dive on a single breath of air taken at the surface before the dive.
Snorkelling allows breathing at the surface with the face submerged, and is used as an adjunct to free diving and scuba.
Atmospheric diving suits and other submersibles which isolate the diver from the ambient environment. These are not considered here.[2]
Liquid breathing systems are still hypothetical and at an early experimental stage. It is hoped that some day practical systems will allow very deep diving. This is not considered here.
A US Navy diver at work. The umbilical supplying air from the surface is clearly visible
Diver in standard diving dress entering the water at Stoney Cove, England
Scuba diver with single cylinder and open circuit regulator
This is the diving equipment worn by or carried by the diver for personal protection or comfort, or to facilitate the diving aspect of the activity, and may include a selection from:
Boiler suit overalls are often worn over the thermal protection suit by commercial divers as abrasion protection for the more easily damaged and expensive diving suit.[6][7]
In very warm water (temperatures of 26-30 °C), many types of tough, long, everyday clothing provide protection, as well as purpose made garments such as dive skins (made of lycra) and shorty wetsuits. In some cases, simple regular swimsuits are also used.[8]
Diving suit hoods are worn mainly for thermal protection, but also provide some impact protection and some protection from environmental contact with contaminants and stinging animals like jellyfish.[9]
Diving boots - With dry suits, the boots are usually integrated.[3]
This equipment includes buoyancy control equipment and mobility equipment:
Buoyancy control is achieved by ballasting with diving weights and compensating for buoyancy changes during the dive using a buoyancy compensator:
Diving weighting system - to counteract the buoyancy of the diving suit and diver to allow descent. Professional divers may use additional weighting to ensure stability when working on the bottom
Buoyancy compensator, also known as Buoyancy Control Device, BCD or BC - is usually a back mounted or sleeveless jacket style device which includes an inflatable bladder used to adjust the buoyancy of the diver under water, and provide positive buoyancy at the surface. The buoyancy compensator is usually an integral part of the harness system used to secure the scuba set to the diver. The earlier collar style buoyancy compensator is seldom used any more.
Mobility equipment allows the diver to move through the water and maneuver on the spot:
These are the equipment used for monitoring the course of the dive and following the dive plan when undesirable events are avoided. They include planning and monitoring the dive profile, gas usage and decompression, navigation, and modifying the plan to suit actual circumstances.
Depth gauge lets the diver monitor depth, particularly maximum depth and, when used with a watch and Decompression tables, also allows the diver to monitor decompression requirements. Some digital depth gauges also indicate ascent rate which is an important factor in avoiding decompression sickness
Pneumofathometer is the surface supplied diving depth gauge which displays the depth of the diver at the surface control panel. It uses hydrostatic back-pressure on a low flow rate open ended air hose to the diver to indicate depth.
Diving watch is used with depth gauge for decompression monitoring when using decompression tables. Largely superseded by dive computers, where elapsed time is one of the standard displays, and time of day may also be available.
Dive timer is an instrument that displays and records depth and elapsed time during the dive. It is usually possible to extract the information after the dive. This function is often available as "Gauge setting" on dive computers.
Diving compass for underwater navigation. This may be a regular magnetic compass, but is often a selectable function of a dive computer, where a miniature magnetometer is used.
Submersible pressure gauge, also known as a "contents gauge" is used to monitor the remaining breathing gas supply in scuba cylinders.
Dive computer helps the diver to avoid decompression sickness by indicating the decompression stops needed for the dive profile. Most dive computers also indicate depth, time and ascent rate. Some also indicate oxygen toxicity exposure and water temperature, and may provide other functions. A display of cylinder pressure is available on air-integrated computers, either via a direct high pressure hose, or remotely via a pressure transducer and through-water transmission.
Distance line, guide line, or "come-home-line" can be used to guide the diver back to the start point and safety in poor visibility.
A cave line is a line laid by a diver while penetrating a cave to ensure that the way out is known. Permanent cave lines are marked with line markers at all junctions, indicating the direction along the line toward the nearest exit.
Underwater vision is significantly affected by several factors. Objects are less visible because of lower levels of natural illumination and are blurred by scattering of light between the object and the viewer, also resulting in lower contrast. These effects vary with wavelength of the light, and color and turbidity of the water. The human eye is unable to focus when in direct contact with water, and an air space must be provided. Voice communication requires special equipment, and much recreational diver communication is visual and based on hand signals.
Full face masks protect the face from dirty or cold water and reduce risk by securing the gas supply to the diver's face. If it contains no mouthpiece, the diver can talk, allowing the use of communications equipment.
Half masks cover only the eyes and nose. The diver breathes from a separate mouthpiece on the regulator or rebreather.
A prescription mask, or glasses which can be mounted inside the mask or helmet to provide clear vision underwater, enhancing the experience and safety for those with vision problems. A prescription mask contains lenses mounted in the scuba mask frame or bonded to the original viewports.
Diving helmets are often used for surface-supplied diving. They provide the same benefits as the full face mask but provide a very secure connection of the gas supply to the diver and additionally protect the head.
Underwater writing slates and pencils are used to transport pre-dive plans underwater, to record facts while underwater and to aid communication with other divers.
Dive lights, which are usually waterproof and pressure rated torches or flashlights, are essential for safety in low visibility or dark environments such as night diving and wreck and cave penetration. They are useful for communication and signalling both underwater and on the surface at night. Divers need artificial light even in shallow and clear water to reveal the red end of the spectrum of light which is absorbed as it travels through water. Underwater video lights can serve the same purpose.
Hand-held sonar for a diver can provide a synthetic view using ultrasonic signals emitted and processed by an electronic device and displayed on a screen.
Ultrasonic signalling devices which attract the buddies attention by vibration have been marketed and may have some limited utility.[11]
A diving half mask provides clear sight and protection for the eyes.
A full face mask covers the eyes, nose and mouth.
One piece LED dive light with soft Goodman type handle
Diving safety equipment in the broader sense would include all equipment that could make a dive safer, by reducing a hazard, reducing the probability of an adverse event, or mitigating its effects. This would include basic equipment such as primary breathing apparatus, exposure protection, buoyancy management equipment and mobility equipment. The more specific meaning is equipment primarily and explicitly used to improve safety of a dive or diving operation. Equipment intended to improve safety in the second sense includes:
Diver's safety harness, to which a lifeline may be attached, including bell harness, AR vest, or jump jacket.[6]
Lifeline (or tether): A line from the diver to a tender at the surface control point, which may be used for:[12]
communications, by diving line signals,
to allow the diver to be found by the stand-by diver following the line,
to provide a guideline to the surface control point to guide the diver on return,
to assist the diver to maintain position in a current,
in an emergency, to recover the diver to the surface, and
in some cases lift the diver out of the water.
Shotline: A line connecting a shot weight to a marker buoy, used to mark a dive site and provide a vertical reference for descent and ascent.[13]
Buddy line: A short line or strap connecting two divers in the water, used to prevent them from being separated in poor visibility and for communication by line signals.[14]
Jonline: A short line or webbing strap to tether the diver to the shotline in a current.[15]
Surface marker buoy, which indicates the position of the divers to people at the surface.[16]
DSMB - (Delayed, or deployable surface marker buoy), or decompression buoy which is inflated at the start of, or during the ascent, to indicate the position of the divers to the surface team, and as a signal that the divers are ascending.[16]
Cutting tool
Knife to cut lines, nets or to pry or dig. Not intended for personal protection against underwater predators as it is generally ineffective for this purpose.
Diver's net or line cutter. This is a small handheld tool carried by scuba divers to extricate themselves if trapped in fishing net or fishing line. It has a small sharp blade such as a replaceable scalpel blade inside the small notch. There is usually a hole at the other end of the handle for a lanyard to tether the cutter to the diver.
Trauma shears. Very effective as a line cutter, with low risk of inadvertent injury or damage. Usually carried in a pocket or special purpose sheath.
Automatic diver recovery devices which inflate the BCD if the diver stops breathing have been marketed. They are not generally used and the risks may outweigh possible benefits.
Front view of jacket style diver harness with removable weight pockets
Backup or redundant equipment is equipment carried in case of failure of the primary equipment. This may be safety critical equipment necessary to allow safe termination of the dive or equipment carried to improve the probability of successfully completing the task of the diving operation if the primary equipment fails. The most common example of the former is bailout gas, carried routinely by solo, technical, and professional scuba divers, and most surface-supplied divers. Solo and technical divers may also carry a backup mask, dive computer, decompression gas and other equipment based on risk assessment for the planned dive.[18] Some backup equipment may be spread amongst a diving team, when instant availability is nor critical, this practice is termed team redundancy.[19]
Diving reel, dive spool or line holder to store and transport a distance line or line for a surface marker buoy. A dive spool, or line spool, is a short cylindrical tube with a large flange at each end, around which a length of line can be wound, and a line holder is a flat H-shaped frame or piece of rigid sheet material on which a length of line can be wound, as an alternative to a reel or spool. The line may be used with a surface marker buoy or a delayed surface marker buoy (decompression buoy), where negative buoyancy of the spool or line holder will help with unwinding the line underwater.[20]
Dry bag to carry items that must stay dry on the boat.
Dive bag to hold personal dive equipment for travel. Soft bags are traditional for local use, when the dive gear may be wet when packed after use. For air travel, hard and soft bags, including those with wheels and telescopic handles are available.[21]
Vinyl toolbag with bolt snaps for securing to harnessDiving tool bag to carry tools that may be required for the job. Various types and sizes are available.[22]
Reef hook to hold onto a reef in a current. This is a metal rod with a handle and a bent tip to grip the reef surface. It is claimed to do less environmental damage than the diver's hand, and is also less likely for the diver to injure themself on sharp substrate. A reef hook may have a single or double claw tip, and may have a rope, webbing or coiled plastic coated lanyard, and may be clipped to the diver's harness at the other end for hands-free use. When hanging off the reef at the end of the lanyard the diver can keep sufficiently clear of the reef to prevent fin-strike damage while effortlessly maintaining position in a moderate current. Some skill is required for safe and effective use.[23][24]
Surface supplied diver rescue tether with soft eye and bolt snapA rescue tether, or rescue rope, is a short lanyard or strap carried by a surface supplied stand-by diver to be used to tether an unresponsive diver to the standby diver during a rescue. It is attached at one end to a D-ring on the stand-by diver's harness, and has a clip at the other end which may be secured to a D-ring on the casualty's harness to allow the rescuer the use of both hands during the return to the bell or surface.
A jackstay is a form of guideline laid between two points to guide the diver during a search or to and from the workplace or to support and guide equipment for transport between two points.[6]
Lifting bags, an item of diving equipment consisting of a robust and air-tight bag with straps, which is used to lift heavy objects underwater by means of the bag's buoyancy when filled with air.[25]
A shot line, consisting of a weight, line and buoy, is used to mark the location and identify the ascent and descent point of a dive site, allowing divers to navigate to and from the surface and to do decompression stops at a safe location and to help control rate of ascent and descent.[26]
Decompression trapeze is used to assist in maintaining correct depth during in-water decompression stops.[27]
A downline is a line from the surface to underwater workplace used to control descent, ascent and the transfer of tools, materials and other equipment between the surface and the workplace.[6] A weighted version suspended from the surface is used to control working depth when blue-water diving,[29] It is similar in function to a jackstay, with an emphasis on the vertical dimension. The terms are largely interchangeable – a downline can be considered a predominantly vertical jackstay.
Surface support equipment connected with diving and underwater work
Boarding ladders, particularly the Christmas tree ladder configuration, with a single central rail and cantilevered rungs on both sides, which allows a diver to climb while wearing fins.[30]
Tools and equipment too large or too heavy to be carried by a diver are generally lowered to the worksite from the surface platform. They are mostly used in professional diving applications.
Remotely operated underwater vehicle - for locating dive sites, observing the environment, conducting visual searches, monitoring divers or performing physical work
Life support equipment must be maintained and tested before use to ensure that it remains in serviceable condition and is fit for use at the time. Pre-dive inspection and testing of equipment at some level is standard procedure for all modes and applications of diving. The use of checklists is known to improve reliability of inspection and testing, and may be required by the applicable code of practice or operations manual, or manufacturer's operating instructions. Inadequate pre-dive checks of breathing apparatus can have fatal consequences for some equipment, such as rebreathers, or may require the diving operation to be aborted without achieving its objective.
Maintenance can be categorised as:
Planned periodical maintenance, such as annual service and inspection of breathing apparatus, pressure equipment, lifting gear and other items according to manufacturers' recommendations or legislation.
Cleaning and inspection after use, and appropriate storage. A large part of this is washing off salt water to prevent it from drying on the equipment and leaving corrosive brine or abrasive salt deposits, which can cause accelerated deterioration of some materials and jamming of moving parts. The ultraviolet component of sunlight can also damage non-metallic components and equipment, and ozone produced by electrical equipment is known to adversely affect some materials, such as the latex seals on dry suits. Most diving equipment will last better if stored in a cool, dry, well ventilated place out of direct sunlight.
Diving equipment may be exposed to contamination in use and when this happens it must be decontaminated This is a particular issue for hazmat diving, but incidental contamination can occur in other environments. Personal diving equipment shared by more than one user requires disinfection before use. Shared use is common for expensive commercial diving equipment, and for rental recreational equipment, and some items such as demand valves, masks, helmets and snorkels which are worn over the face or held in the mouth are possible vectors for infection by a variety of pathogens. Diving suits are also likely to be contaminated, but less likely to transmit infection directly.[34][35]
When disinfecting diving equipment it is necessary to consider the effectiveness of the disinfectant on the expected pathogens, and the possible adverse effects on the equipment. Some highly effective methods for disinfection can damage the equipment, or cause accelerated degradation of components due to incompatibility with materials.[36]
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The diving equipment market sectors are commercial diving, military diving, recreational and technical scuba, freediving, and snorkelling. with scientific diving using a mix of recreational, technical, and commercial equipment.
The commercial diving market is relatively small, but occupational safety issues keep cost of operations high and there is work that must be done in support of various industries, particularly the oil and gas industry, that make money available for high reliability equipment in small quantities. The military market is similarly constrained by small quantities, and there is a lot of overlap with commercial equipment where the applications are similar, but the technical requirements for stealth operations drive development of different equipment.
Recreational scuba and snorkelling are the largest markets, in which there is the most competition between manufacturers for market share, and in which the buyers are least knowledgeable about the technology and most susceptible to persuasion by advertising.
Technical diving is a niche market, where the buyers are willing to take higher risks than commercial operators, and there is enough money available to support a small number of manufacturers developing new technology. Scientific diving is also a small market, and tends to overlap the other sectors, using what is available, and occasionally driving development of new technology for special applications.
With the partial exception of breath-hold diving, the development of underwater diving capacity, scope, and popularity, has been closely linked to available technology, and the physiological constraints of the underwater environment which the technology allows divers to partially overcome.
The Diving Equipment and Marketing Association (DEMA, formerly the Diving Equipment Manufacturers Association),[37][38] is an international organization for the promotion and growth of the recreational scuba diving and snorkeling industry. It is a non-profit, global organization with more than 1,300 members, which promotes scuba diving through consumer awareness programs and media campaigns such as the national Be a Diver campaign; diver retention initiatives such as DiveCaching; and an annual trade-only event for businesses in the scuba diving, action watersports and adventure/dive-travel industries, DEMA Show.[39] Board Members serve three-year terms.[40]
The purposes and objectives of the Association are published as:[41]
To promote the advancement of the diving industry, to promote and encourage the growth of diving activities, and to enhance the growth and public enjoyment of the sport of diving.
To establish continuing business education programs to aid industry members, their officers and employees.
To facilitate the exchange of information among industry members, through experts, internet-based programming, manuals and conferences, and other media on such subjects as quality control, general industry statistics, governmental regulations, product standards and/or certification, standardized methods of keeping books and records, and related topics of industry interest.
To support the diving industry with communication services, media relations and resources.
To support the diving industry in monitoring and communicating on legislation that impacts diving and to represent the industry before the executive, legislative and judicial branches of government throughout the United States and in foreign jurisdictions.
To support the diving industry in the monitoring and protection of the environment through education and activities.
GOST 22469:1977 USSR/CIS standard, Ласты резиновые для плавания. Общие технические условия. Swimming rubber flippers. General specifications.[43]
DIN 7876:1980 German standard, Tauchzubehör. Schwimmflossen. Maße, Anforderungen und Prüfung. Diving accessories for skin divers. Flippers. Dimensions, requirements and testing.[44]
GOST 20568 compliant Russian and Ukrainian diving masks.
BS 4532:1969 British standard, Specification for snorkels and face masks. Amended 1977.[50]
GOST 20568:1975 USSR/CIS standard, Маски резиновые для плавания под водой. Общие технические условие. Rubber masks for submarine swimming. General specifications.[51]
DIN 7877:1980 German standard, Tauch-Zubehör. Tauchbrillen. Sicherheitstechnische Anforderungen und Prüfung. Diving accessories for skin divers. Diver's masks. Requirements and testing.[52]
BS 4532:1969 British standard, Specification for snorkels and face masks. Amended 1977.[50]
DIN 7878:1980 German standard, Tauch-Zubehör; Schnorchel; Maße, Anforderungen, Prüfung. Diving accessories for skin divers. Snorkel. Technical requirements of safety, testing.[59]
DIN 7878:1991 German standard, Tauch-Zubehör; Schnorchel; Sicherheitstechnische Anforderungen und Prüfung. Diving accessories for skin divers. Snorkel. Safety requirements and testing.[61]
EN 1972:1997 – European standard design and manufacture of snorkels European standard, Diving accessories. Snorkels. Safety requirements.[62]
EN 1972:2015 European standard, Diving equipment. Snorkels. Requirements and test methods.[63]
^ abcBeyerstein, G (2006). Commercial Diving: Surface-Mixed Gas, Sur-D-O2, Bell Bounce, Saturation. In: Lang, MA and Smith, NE (Eds). Proceedings of Advanced Scientific Diving Workshop (Report). Smithsonian Institution, Washington, DC.
^Gronfeldt, Thomas (11 November 2016). "Gear Review: The Buddy-Watcher". scubadiverlife.com. Archived from the original on 26 October 2017. Retrieved 25 October 2017.
^Department of Labour (11 January 2002). Diving regulations 2001 of the Occupational Health and Safety Act 85 of 1993. Government Gazette, Republic of South Africa. Vol. 438. Pretoria: Government Printer.
^Gurr, Kevin (August 2008). "13: Operational Safety". In Mount, Tom; Dituri, Joseph (eds.). Exploration and Mixed Gas Diving Encyclopedia (1st ed.). Miami Shores, Florida: International Association of Nitrox Divers. pp. 165–180. ISBN978-0-915539-10-9.
^Gentile, Gary (1998). The Technical Diving Handbook. Gary Gentile Productions. ISBN1-883056-05-5.
^Staff (4 March 2014). "CMAS Self-Rescue Diver". Standard Number: 2.B.31 / BOD no 181 ( 04-18-2013 ). CMAS. Archived from the original on 14 April 2017. Retrieved 13 April 2017.
^Jablonski, Jarrod (2006). "4: DIR Philosophy". Doing It Right: The Fundamentals of Better Diving. High Springs, Florida: Global Underwater Explorers. pp. 53–54. ISBN0-9713267-0-3.
^NOAA Diving Program (U.S.) (28 Feb 2001). Joiner, James T. (ed.). NOAA Diving Manual, Diving for Science and Technology (4th ed.). Silver Spring, Maryland: National Oceanic and Atmospheric Administration, Office of Oceanic and Atmospheric Research, National Undersea Research Program. ISBN978-0-941332-70-5. CD-ROM prepared and distributed by the National Technical Information Service (NTIS) in partnership with NOAA and Best Publishing Company
^ abBS 4532: Specification for snorkels and face masks. London: British Standards Institution. 1969. Amendment Slip No. 1 to BS 4532:1969 Snorkels and face masks, 30 December 1977.
^Deutsches Institut für Normung (1980). Tauch-Zubehör. Tauchbrillen. Sicherheitstechnische Anforderungen und Prüfung [Diving accessories for skin divers. Diver's masks. Requirements and testing]. DIN 7878 (Report) (in German). Berlin/Cologne: Beuth Verlag.
^American National Standards Institute: ANSI Z87.11:1985: Underwater Safety. Recreational Skin and Scuba Diving. Lenses for Masks (Technical report). New York: American National Standards Institute. 1985.
^CNS 12497: 潛水鏡. Diving mask. Bureau of Standards, Metrology and Inspection, Republic of China. Archived from the original on 2023-05-21. Retrieved 2019-07-23. Preview available at cnsonline.com.tw
^Deutsches Institut für Normung (1991). Tauch-Zubehör: Schnorchel. Sicherheitstechnische Anforderungen und Prüfung [Diving accessories for skin divers; snorkel; safety requirements and testing]. DIN 7878 (Report) (in German). Berlin/Cologne: Beuth Verlag.
^BS EN 1972: Diving accessories - Snorkels - Safety requirements and test methods. London: British Standards Institution. 1997.
^BS EN 1972: Diving equipment - Snorkels - Requirements and test methods. London: British Standards Institution. 2015.
A US Navy diver at work. The umbilical supplying air from the surface is clearly visible
Diver in standard diving dress entering the water at Stoney Cove, England
Scuba diver with single cylinder and open circuit regulator
Free-diver with monofin, ascending
The Newtsuit is an atmospheric diving suit which has fully articulated rotary joints in the arms and legs.
Early twin cylinder set with twin hose regulator
Twin scuba cylinders with isolation manifold
Charging a small bailout cylinder from a larger aluminium scuba cylinder
Scuba regulator: First stage with primary and secondary demand valves, submersible pressure gauge and low pressure hose for BC inflation.
Technical diver with back mounted open circuit scuba and sling mounted decompression cylinders
Diving with a closed circuit rebreather
Russian made IDA-71 rebreather set
Heavy standard diving helmet, lightweight demand helmet and band mask
Diver wearing lightweight demand helmet
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Full wet suit
Dry suits
Short and full length wet suits
Wet suit boots
Neoprene diving gloves
Chain mail shark suit
Shark proof cage
Atmospheric diving suit
Jacket buoyancy compensator
Diver propulsion vehicle (scooter)
Weight belt
Swim fins
A depth gauge and submersible pressure gauge
Submersible pressure gauge
A surface supply panel for four divers showing four pneumofathometer gauges
A watch sized dive computer incorporating an electronic compass and the ability to display cylinder pressure when used with an optional transmitter
Dive computer showing the log of a previous dive
Nav finder and underwater compass - basic underwater navigation tools.
Diving compass in aftermarket wrist mount with bungee straps
Dive computers in compass mode
50 metres of line on a reel
Line arrow marker
A miniature submersible pressure gauge (mini SPG) used on pony cylinders
A diving half mask provides clear sight and protection for the eyes.
A full face mask covers the eyes, nose and mouth.
One piece LED dive light with soft Goodman type handle
A "canister" style dive light
Front view of jacket style diver harness with removable weight pockets
Scuba diver's net cutter. 7 inches long
Underwater Kinetics general purpose dive knife
Trilobite line cutter with sheath on diving harness
Trauma shears
DiverGuard automatically inflates the buoyancy compensator if the diver stops breathing.
Spool with line and double-ender clip
Dive reel with stored DSMB
A stainless steel line holder with a 20-metre line
Surface supply air panels. On the left for two divers, on the right for three divers
A hard-wired diver communications unit mounted in a waterproof box for convenience of transport and protection.
Personnel Transfer Capsule - a dry bell
Christmas tree style diver's boarding ladder
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