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Safety concept in underwater diving
diving, technical diving and nitrox diving, the maximum operating depth (MOD) of a breathing gas is the depth below which the partial pressure of oxygen (pO2)
Maximum_operating_depth
Measures of a submarine's ability to operate underwater
design depth. Also known as the maximum operating depth (or the never-exceed depth), this is the maximum depth at which a submarine is allowed to operate under
Submarine_depth_ratings
Semi-submersible offshore drilling rig
(221 ft) and depth of 36.6 metres (120 ft). It had a maximum drilling depth of 6.1 kilometres (3.8 mi), and it could operate at a water depth of 460 metres
Byford_Dolphin
Class of nuclear-powered fast attack submarines of the United States Navy
maximum operating depth of the Los Angeles class as 650 ft (200 m), while Patrick Tyler, in his book Running Critical, suggests a maximum operating depth
Los_Angeles-class_submarine
Toxic effects of breathing oxygen at high partial pressures
calculate a maximum operating depth for oxygen-rich breathing gases, and cylinders containing such mixtures should be clearly marked with that depth. The risk
Oxygen_toxicity
Gas used for human respiration
considered to have a safe depth limit of about 40 metres (130 feet) for most divers, although the maximum operating depth (MOD) of air taking an allowable
Breathing_gas
Diving mode and decompression technique
both upwards and downwards (mixed excursion). The depth range between maximum and minimum excursion depth is called the excursion range or excursion window
Saturation_diving
British ocean liner (1907–1915)
boilers (which fitted the forward space where the ship narrowed), operating at a maximum 195 pounds per square inch (1,340 kPa) and containing 192 individual
RMS_Lusitania
Acoustic sensing method
sonars operated at a relatively high frequency of 20–30 kHz, to achieve directionality with reasonably small transducers, with typical maximum operational
Sonar
British volunteer cave diver who specialises in rescues
how's that?" In 2004, Volanthen and Stanton set a record for the greatest depth achieved in a British cave, diving 76 m (249 ft) at Wookey Hole in Somerset
John_Volanthen
Disorder caused by dissolved gases forming bubbles in tissues
It may happen when leaving a high-pressure environment, ascending from depth, or ascending to altitude. A closely related condition of bubble formation
Decompression_sickness
French oceanographer and author (1910–1997)
Embiez islands in Var, with Philippe Tailliez and Frédéric Dumas, using a depth-pressure-proof camera case developed by mechanical engineer Léon Vèche,
Jacques_Cousteau
Set of detailed instructions to assist in workplace safety
(documented as standard operating procedures) used in any manufacturing process that could affect the quality of the product. Standard Operating Procedures are
Standard_operating_procedure
U.S. Navy's special operations force
envisioned as a "guerrilla amphibious organization of Americans and Chinese operating from coastal waters, lakes, and rivers employing small steamboats and
United_States_Navy_SEALs
Crewed full ocean depth rated submersible
Factor's port thruster group. The vessel is certified by DNV for a maximum dive depth of 11,000 m (36,000 ft), exceeding that of the Challenger Deep, the
DSV_Limiting_Factor
Medical condition of lack of oxygen in the tissues
pressures due to altitude, by breathing hypoxic breathing gas at an unsuitable depth, by breathing inadequately re-oxygenated recycled breathing gas from a rebreather
Hypoxia_(medicine)
Swimming underwater, breathing gas carried by the diver
risk of oxygen toxicity, which becomes unacceptable below the maximum operating depth of the mixture. To displace nitrogen without the increased oxygen
Scuba_diving
Organ system for circulating blood in animals
which specialise in the heart, and cardiothoracic surgeons specialise in operating on the heart and its surrounding areas. Vascular surgeons focus on disorders
Circulatory_system
Change in sea level due to gravity
heights and times. To calculate the actual water depth, add the charted depth to the published tide height. Depth for other times can be derived from tidal curves
Tide
Japanese manned suicide torpedoes used by the Imperial Navy in World War II
Kerosene and oxygen Maximum range: 78 km (42 nmi) Cruising speed: 22 km/h (12 kn) Maximum speed: 56 km/h (30 kn) Maximum operating depth: 80 m (260 ft) Number
Kaiten
Breathing gas, mixture of nitrogen and oxygen
teach the use of two depth limits to protect against oxygen toxicity. The shallower depth is called the "maximum operating depth" and is reached when
Nitrox
British cave diver who specialises in rescues
seriously." In 2004 Stanton and Volanthen set a world record for greatest depth achieved in a British cave, cave diving 76 m (249 ft) at Wookey Hole in
Rick_Stanton
Pirate Blackbeard's ship
uncertain, and there is no record of her actions prior to 1710 when she was operating as a French privateer as La Concorde. Surviving features of the ship's
Queen_Anne's_Revenge
Topics referred to by the same term
subculture Mod revival, late 1970s Honour Moderations, Oxford exams Maximum operating depth in scuba diving Mod Cup, a shinty trophy A module in modular scheduling
Mod
Scuba cave diving incident in South Australia
depth of about 80 metres (260 ft), and another to the east reaches a maximum depth of 124 metres (407 ft). Because of the size of the hole and the height
1973 Mount Gambier cave diving accident
1973_Mount_Gambier_cave_diving_accident
Search for a missing Boeing 777 in the southern Indian Ocean
was aborted because the sea bed was considerably deeper than the maximum operating depth of Bluefin. Scanning subsequently resumed and after covering 42
Search for Malaysia Airlines Flight 370
Search_for_Malaysia_Airlines_Flight_370
Medical treatment at raised ambient pressure
or pits. The operating pressure depends on the application. Chambers used for clinical hyperbaric oxygen therapy commonly have a maximum allowable working
Hyperbaric_medicine
Underwater diving using self contained breathing gas recycling apparatus
very shallow maximum operating depth limit, due to oxygen toxicity considerations. Active addition SCRs vary in complexity, but all operate with a breathing
Rebreather_diving
Narcotic effects of respiratory nitrogen
is a reversible alteration in consciousness that occurs while diving at depth. It is caused by the anesthetic effect of certain gases at high partial
Nitrogen_narcosis
Special forces unit of the Royal Navy
as operating behind enemy lines destroying lines of communication, installations and gathering intelligence. During the Korean War the SBS operated from
Special_Boat_Service
USMC deep reconnaissance unit
understood that his recon Marines would be operating 50 to 150 miles away from their littoral or operating area, or from any naval support. In order to
United States Marine Corps Force Reconnaissance
United_States_Marine_Corps_Force_Reconnaissance
Special forces unit of the Australian Army
March 2002. During the operation SASR teams were to provide on-location, in-depth operational intelligence and reconnaissance after they infiltrated the Shahi-Kot
Special_Air_Service_Regiment
Underwater diving to a depth beyond the norm
Deep diving is underwater diving to a depth beyond the normal range accepted by the associated community. In some cases this is a prescribed limit established
Deep_diving
Tactical scuba diver
rebreathing equipment will stay within a depth limit of 20 feet (6.1 m) with limited deeper excursions to a maximum of 50 feet (15 m) because of the risk
Frogman
Breathing gas consisting of oxygen, helium and nitrogen
Lowering the oxygen content of a breathing gas mixture increases the maximum operating depth and duration of the dive before which oxygen toxicity becomes a
Trimix_(breathing_gas)
US government scientific agency
Satellite, Data, and Information Service (NESDIS) was created by NOAA to operate and manage the US environmental satellite programs, and manage NWS data
National Oceanic and Atmospheric Administration
National_Oceanic_and_Atmospheric_Administration
Australian technical diver (1954–2005)
descended to a depth of 270 metres (890 ft) at Bushman's Hole, South Africa, breaking the following records: Depth on a rebreather Depth in a cave on a
Dave_Shaw
French world record-setting freediver
Lauderdale, Audrey Mestre broke the female world record by free diving to a depth of 125 meters (410 ft) on a single breath of air.[citation needed] A year
Audrey_Mestre
Diving in water-filled caves
available. Where the depth or other constraints prevent divers from exploring in person, tethered and untethered remotely operated underwater vehicles
Cave_diving
Cuban freediver also known as "Pipin"
where he established his first known world record of 112 meters (367 ft) depth in November 1989. Shortly thereafter he defected to Italy and later migrated
Francisco_Ferreras
Submersible that traveled to the Challenger Deep
the submersible to the bottom of the New Britain Trench, reaching a maximum depth of 8,221 m (26,972 ft). There, he found a wide plain of loose sediment
Deepsea_Challenger
Articulated pressure-resistant anthropomorphic housing for an underwater diver
factors affecting design are the ambient hydrostatic pressure of the maximum operating depth, and ergonomic considerations regarding the potential range of
Atmospheric_diving_suit
South African diver
by the high work-rate of breathing at depth. Two weeks after Dreyer's death, Theo hired a small, remotely operated sub used by the De Beers mining company
Deon_Dreyer
Pressure of a component gas in a mixture
determines the maximum operating depth of a gas mixture. Narcosis is a problem when breathing gases at high pressure. Typically, the maximum total partial
Partial_pressure
Injury due to pressure difference between gas filled space and adjoining tissue
volume during ascent. A scuba or surface-supplied diver breathing gas at depth from underwater breathing apparatus fills their lungs with gas at an ambient
Barotrauma
Hyperbaric pressure vessel for human occupancy used in diving operations
maximum working pressure. Valves are generally duplicated inside and outside and are labelled to avoid confusion. It is usually possible to operate a
Diving_chamber
Italian freediver (born 1992)
On 18 October 2019, Zecchini became the first woman to have reached a depth of −100m exclusively with the use of her arms (free immersion), during the
Alessia_Zecchini
Polish special forces unit
missions. On 27 June 1997, during Operation "Little Flower", a mixed team operating under the authority of the International Criminal Tribunal for the former
GROM_Military_Unit
Exposure of tissues to abnormally high concentrations of oxygen
partial pressure of oxygen in any given gas mixture will increase with depth. Atmospheric air becomes hyperoxic during the dive, and a hyperoxic gas
Hyperoxia
Retired US Navy officer and professor of oceanography (born 1942)
and his team discovered they had imploded from the immense pressure at depth. It littered thousands of pieces of debris all over the ocean floor. Following
Robert_Ballard
Vascular blockage by air bubbles
in. This is one reason why surgeons must be particularly careful when operating on the brain, and why the head of the bed is tilted down when inserting
Air_embolism
Tethered underwater mobile device operated by a remote crew
underwater machines that are often used to explore the ocean depth while being operated by people at the surface, usually from a control room. ROVs are
Remotely operated underwater vehicle
Remotely_operated_underwater_vehicle
Mixing and filling cylinders with breathing gases for use when scuba diving
risk of oxygen toxicity, which becomes unacceptable below the maximum operating depth of the mixture. To displace nitrogen without the increased oxygen
Gas_blending_for_scuba_diving
US Marine Corps special forces unit
amphibious light infantry warfare, particularly in landing in rubber boats and operating behind the lines. "Edson's" Raiders of 1st Marine Raiders Battalion and
Marine_Raider_Regiment
American cave and deep diving pioneer and record breaker
perhaps to sort out gas issues. His wrist-mounted dive computer read a maximum depth of 906 feet (276 m). The cause of Exley's death could not be determined
Sheck_Exley
Closed or semi-closed circuit scuba
oxygen and inert components. A gas mix which has a maximum operating depth that is safe for the depth of the dive being planned, and which will provide
Diving_rebreather
Reconnaissance assets of Marine Air-Ground Task Force
are conducted by Marine Recon units are characterized by its degree in depth of penetration. This greatly increases the mission time, risk, and support
United States Marine Corps Reconnaissance Battalions
United_States_Marine_Corps_Reconnaissance_Battalions
Diving beyond the scope of recreational diving
mixture and will also be marked with the maximum operating depth and if applicable, minimum operating depth. Technical diving can be done using air as
Technical_diving
American marine biologist and lecturer
dive, untethered, to the sea ocean floor near Oahu. She set the women's depth record of 381 metres (1,250 ft) which still holds to date. In 1979 she also
Sylvia_Earle
Crewed deep-ocean research submersible
completed sea trials and was certified for operating down to 6,500 meters. As of 2024, Alvin is in active service, operated by the Woods Hole Oceanographic Institution
DSV_Alvin
Distinct layer of temperature change in a body of water
that is not affected by season and lies below the yearly mixed layer maximum depth. Thermoclines can also be observed in lakes. In colder climates, this
Thermocline
Deaths occurring while scuba diving or as a consequence of scuba diving
buoyancy control, equipment misuse, entrapment, rough water conditions, scuba depth record attempts, and pre-existing health problems. Some fatalities are inevitable
Scuba_diving_fatalities
Breathing gas mixed from helium and oxygen
gas diving. The proportion of oxygen in a diving mix depends on the maximum depth of the dive plan, but it is often hypoxic and may be less than 10%.
Heliox
Instrument to calculate decompression status in real time
available to warn the diver when exceeding the no-stop limit, the maximum operating depth for the breathing gas mixture, the recommended ascent rate, decompression
Dive_computer
First ironclad of the US Navy, 1861–1862
discovered almost 111 years after sinking, near Cape Hatteras at 230 feet (70 m) depth at coordinates 35°0′6″N 75°24′23″W / 35.00167°N 75.40639°W / 35.00167;
USS_Monitor
German manufacturer of breathing equipment
approximately 15 kg Gas supply cylinder: 4 litre, 200 bar (standard) Diving depth: 6 msw (100% oxygen) 22 msw (EAN 50) 30 msw (EAN 40) 40 msw (EAN 32) Dive
Dräger_(company)
Cylindrical container for storing pressurised gas
group of cylinders on a lifting frame with no functional connections. The maximum combined cylinder volume for a bundle is 3000 litres for non-toxic gases
Gas_cylinder
Self-propelled deep-diving crewed submersible
International Hydrodynamics of Vancouver in British Columbia with a maximum operating depth of 2,000 metres (1.2 mi) capable of dive durations of 7 to 10 hours
Deep-submergence_vehicle
Chamber for transporting divers vertically through the water
diving bell is a rigid chamber used to transport divers from the surface to depth and back in open water, usually for the purpose of performing underwater
Diving_bell
Russian multiple world record holding freediver (1962–2015)
giving a private lesson dive near Formentera, Spain. She went down to a depth of 40 metres (131 ft.), not as deep as normal; but, caught by a current
Natalia_Molchanova
Facility for supporting saturation diving projects
position. Heave compensation gear may be used to maintain a constant operating depth in a seaway. A decompression/recompression chamber may be included
Saturation_diving_system
Descending below the surface of the water to interact with the environment
methods to this day. Following Haldane's recommendation, the maximum safe operating depth for divers was extended to 61 metres (200 ft). The US Navy continued
Underwater_diving
Abnormally high tissue carbon dioxide levels
{P_{et_{CO_{2}}}}} rose markedly with exertion even when the divers breathed air at a depth of only a few feet. A variety of reasons exist for carbon dioxide not being
Hypercapnia
Cloudiness of a fluid
disk is lowered into the water until it can no longer be seen; the depth (Secchi depth) is then recorded as a measure of the transparency of the water (inversely
Turbidity
Military Engineers of the British Army
Engineers in a variety of roles, including the Submarine Mining Service operating the boats required to tend the submarine mine defences that protected
Royal_Engineers
Firearm firing gyroscopic rockets in the 1960s
flight like an unpowered bullet. A bullet has maximum kinetic energy at the muzzle; a rocket has maximum kinetic energy immediately after its fuel is expended
Gyrojet
Submerged ridge of rock, coral or other material
Reefs may be classified in terms of their origin, geographical location, depth, and topography. For example a tropical coral fringing reef, or a temperate
Reef
Instrument that indicates depth below a reference surface
At greater depths, it becomes inaccurate. The maximum depth cannot be recorded with this type of depth gauge, and accuracy is strongly affected by temperature
Depth_gauge
Diver who remains underwater for 24 hours or more
After sinking, the boat came to rest upside-down on the sea floor at a depth of 30 m (98 ft); eleven crew members perished. As the Jascon-4 filled with
Aquanaut
British defense industry manufacturing company
dual mode oxygen or semi-closed circuit mixed gas rebreather with maximum operating depth normally limited to 24 metres, but can be set to 55 metres, which
Cobham_Limited
Swimming while inhaling through a snorkel
impossible to pinch the nose if needed to equalize pressure at greater depth. Trained scuba divers are likely to avoid such devices, however, snorkel
Snorkeling
Submersible used for rescue of people from disabled submarines and submersibles
24 people at a time at depths of up to 600 m (1,969 ft). Their maximum operating depth is 1,500 m (4,921 ft). Power is provided by two large batteries
Deep-submergence rescue vehicle
Deep-submergence_rescue_vehicle
Russian freediver (born 1987)
a pool with a monofin on a single breath. Since then, he has focused on depth disciplines and competing in open water. In 2012, he set a world record
Alexey_Molchanov
Breathing gas mixture experimentally used for very deep diving
mixtures to specification InDEPTH (4 March 2020). "Playing with Fire: Hydrogen as a Diving Gas". InDepth. Retrieved 2023-09-08. InDEPTH (31 May 2023). "N=1:
Hydrox_(breathing_gas)
Austrian freediver and world record holder
world record champion, and "the deepest man on earth" having dived to a depth of 253.2 metres (831 feet). Nitsch has held 33 world records across eight
Herbert_Nitsch
Series of Chinese remotely operated underwater vehicles
Specifications: Maximum operating depth: 600 meters The JTD-01 "Deep Eel I" is a salvage, drilling, and pipe-laying robot. It has a maximum operating depth of 200
SJT-class_ROUV
Copper helmet with rubberised canvas diving suit and weighted boots
depth - feet or metres of water column - which would provide the supervisor with a reasonable indication of diver depth. Originally manually operated
Standard_diving_dress
Free-diving self-propelled deep-sea submersible
the Mariana Trench in the Pacific Ocean. The onboard systems indicated a depth of 37,800 ft (11,521 m) but this was later corrected to 35,813 ft (10,916
Bathyscaphe
Scientific study of the ocean
its surfaces and of the animals that fishermen brought up in nets, though depth soundings by lead line were taken. The Portuguese campaign of Atlantic navigation
Oceanography
Manned wet submersible for deploying naval special forces
Navy SEALs and their equipment for special operations missions. It is operated by SEAL Delivery Vehicle Teams. The SDV, which has been in continuous service
SEAL_Delivery_Vehicle
American astronaut and aquanaut (1925–2013)
ocean floor in SEALAB II at a depth of 205 feet (62 m) about 3,000 feet (910 m) off the coast of California. The depth required a cabin gas mixture of
Scott_Carpenter
Human habitable underwater enclosure filled with breathable gas
be submerged to a maximum depth of 300 metres (1,000 ft) over the decade; in reality only three were completed with a maximum depth of 100 metres (330 ft)
Underwater_habitat
Unstable wave
likely. A plunging wave occurs when the ocean floor is steep or has sudden depth changes, such as from a reef or sandbar. The crest of the wave becomes much
Breaking_wave
Underwater diving without breathing apparatus
the competitor at somewhere around 1/3 to 1/4 of the target depth, usually with a maximum of 30m. The second will meet them about 10m shallower, and a
Freediving
Duplication of critical components to increase reliability of a system
using at least two different types of each of the following processors, operating systems, software, sensors, types of actuators (electric, hydraulic, pneumatic
Redundancy_(engineering)
Experimental underwater habitats developed by the United States Navy
Sea at a depth of 61 m (200 ft) for one day on September 6, 1962. Cousteau's habitats included Conshelf I, with a 2-person crew at a depth of 10 m (33 ft)
SEALAB
A cable and/or hose bundle which supplies required consumables to a remote user
surface gas panel, where the supervisor can use it to measure the diver's depth in the water at any time. This is done by measuring pressure of the air
Umbilical_cable
Professional diving on industrial projects
equipment, and small areas of paintwork. Depending on the water temperature, depth and duration of the planned dive, the diver will either use a wetsuit, dry
Commercial_diving
Ship used as a floating base for professional diving projects
relative movement through the splash zone, and heave compensation to minimise depth variation of the bell during the dive. Accommodations must be provided for
Diving_support_vessel
Technical diving safety philosophy
decompression plan. Cylinders are marked with the Enriched Air Percentage, maximum operating depth (MOD) in a clear and easily identifiable manner, and time/date
Doing_It_Right_(scuba_diving)
MAXIMUM OPERATING-DEPTH
MAXIMUM OPERATING-DEPTH
Boy/Male
Italian American
The greatest.
Boy/Male
Indian
Auspicious, Prosperous
Boy/Male
American, Australian, Chinese, French, German, Greek, Latin, Swedish
Greatest
Boy/Male
Bengali, Gujarati, Hindu, Indian, Jain, Kannada, Malayalam, Marathi, Sanskrit
Plenty; Maximum; Intelligent; Young and Dynamic; Earth
Boy/Male
American, Australian, Chinese, Danish, French, German, Latin, Swedish
The Greatest; Form of Maximilian; Great; The Greatest Rival
Boy/Male
Russian American
The greatest.
Boy/Male
Arabic, French, Muslim
Lucky
Boy/Male
Latin
Greatest.
Boy/Male
Arabic, Muslim
Method; Way; Mode; Manner; Operation; Process
Girl/Female
Latin
The best.
Male
French
French form of Latin Maximus, MAXIME means "the greatest."Â
Boy/Male
Latin French
Greatest.
Boy/Male
Arabic
Trusting
Boy/Male
African, Arabic
Far
Boy/Male
Muslim
Auspicious, Prosperous
Boy/Male
Latin
Greatest.
Boy/Male
American, Australian, French, Latin
Greatest
Male
Italian
Italian form of Latin Maximus, MASSIMO means "the greatest."
Male
Russian
(МакÑим) Variant spelling of Russian Maksim, MAXIM means "the greatest." Compare with another form of Maxim.
Girl/Female
Arabic, Muslim
Increase; Excess; High Degree; Maximum; Feminine of Mazid
MAXIMUM OPERATING-DEPTH
MAXIMUM OPERATING-DEPTH
Girl/Female
Tamil
White, One who is as pure as the white colour
Girl/Female
Hebrew
Jehovah is God.
Girl/Female
Indian
Brave one
Surname or Lastname
English
English : occupational name for someone who produced or used malt for brewing, from Middle English malt ‘malt’, ‘germinated barley’ + man ‘man’ (see Malter).
Boy/Male
Indian
Faith, Belief, Faith in Allah
Girl/Female
Anglo, Arabic, Australian, Hebrew, Muslim
Wise; Feminine Form from the Male Dara; A Biblical Descendant of Judah Known for his Wisdom; Princess
Girl/Female
American, Danish, French, German, Greek, Gujarati, Hindu, Indian, Kannada, Malayalam, Marathi, Modern, Russian, Sanskrit, Sindhi, Tamil, Telugu, Ukrainian
Of the Family; Fairy Princess; Beautiful Eyes
Boy/Male
Indian, Punjabi, Sikh
Satisfaction of Heart
Boy/Male
Hindu, Indian
King
Girl/Female
Tamil
Vag-devi | வாக-தேவீ
Goddess of words
MAXIMUM OPERATING-DEPTH
MAXIMUM OPERATING-DEPTH
MAXIMUM OPERATING-DEPTH
MAXIMUM OPERATING-DEPTH
MAXIMUM OPERATING-DEPTH
n.
The greatest quantity or value attainable in a given case; or, the greatest value attained by a quantity which first increases and then begins to decrease; the highest point or degree; -- opposed to minimum.
n.
The act of cooperating, or of operating together to one end; joint operation; concurrent effort or labor.
n.
The act or process of operating; agency; the exertion of power, physical, mechanical, or moral.
a.
Based upon, or consisting of, an operation or operations; as, operative surgery.
pl.
of Maximum
a.
Operating in any way.
n.
That which is operated or accomplished; an effect brought about in accordance with a definite plan; as, military or naval operations.
n.
Minimum.
a.
Producing the appropriate or designed effect; efficacious; as, an operative dose, rule, or penalty.
a.
Greatest in quantity or highest in degree attainable or attained; as, a maximum consumption of fuel; maximum pressure; maximum heat.
pl.
of Minimum
p. pr. & vb. n.
of Operate
n.
In a curve referred to polar coordinates, any point for which the radius vector is a maximum or minimum.
a.
Having the power of acting; hence, exerting force, physical or moral; active in the production of effects; as, an operative motive.
p. pr. & vb. n.
of Onerate
n.
A self-registering thermometer, especially one that registers the maximum and minimum during long periods.
n.
The least quantity assignable, admissible, or possible, in a given case; hence, a thing of small consequence; -- opposed to maximum.
n.
A coarse umbelliferous plant of Europe (Tordylium maximum).
a.
Operating together; as, cooperant forces.
n.
The act of operating or working; operation.