List of diving environments by type

Ice diving

The diving environment is the natural or artificial surroundings in which a dive is done. It is usually underwater, but professional diving is sometimes done in other liquids. Underwater diving is the human practice of voluntarily descending below the surface of the water to interact with the surroundings, for various recreational or occupational reasons, but the concept of diving also legally extends to immersion in other liquids, and exposure to other pressurised environments.<ref name="SA Diving Regulations 2009" /> Some of the more common diving environments are listed and defined here.

The diving environment is limited by accessibility and risk, but includes water and occasionally other liquids. Most underwater diving is done in the shallower coastal parts of the oceans, and inland bodies of fresh water, including lakes, dams, quarries, rivers, springs, flooded caves, reservoirs, tanks, swimming pools, and canals, but may also be done in large bore ducting and sewers, power station cooling systems, cargo and ballast tanks of ships, and liquid-filled industrial equipment. The environment may affect equipment configuration: for instance, freshwater is less dense than saltwater, so less added weight is needed to achieve diver neutral buoyancy in freshwater dives.<ref name="Graver2010" /> Water temperature, visibility and movement also affect the diver and the dive plan.<ref name="Jablonski 2006" /> Diving in liquids other than water may present special problems due to density, viscosity and chemical compatibility of diving equipment, as well as possible environmental hazards to the diving team.<ref name="High risk" />

Benign conditions, sometimes also referred to as confined water, are environments of low risk, where it is extremely unlikely or impossible for the diver to get lost or entrapped, or be exposed to hazards other than the basic underwater environment. These conditions are suitable for initial training in the critical survival skills, and include swimming pools, training tanks, aquarium tanks and some shallow and protected shoreline areas.<ref name="CoP Benign" />

Open water is unrestricted water such as a sea, lake or flooded quarry, where the diver has unobstructed direct vertical access to the surface of the water in contact with the atmosphere.<ref name="Aus Part 3" /> Open-water diving implies that if a problem arises, the diver can directly ascend vertically to the atmosphere to breathe air.<ref name="Divers dictionary" /> Wall diving is done along a near vertical face. Blue-water diving is done in Template:Diving term where the bottom is out of sight of the diver and there may be no fixed visual reference.<ref name="Haddock and Heine" /> Black-water diving is mid-water diving at night, particularly on a moonless night.<ref name="Black-water" /><ref name="Indigo" />

An overhead or penetration diving environment is where the diver enters a space from which there is no direct, purely vertical ascent to the safety of breathable atmosphere at the surface. Cave diving, wreck diving, ice diving and diving inside or under other natural or artificial underwater structures or enclosures are examples. The restriction on direct ascent increases the risk of diving under an overhead, and this is usually addressed by adaptations of procedures and use of equipment such as redundant breathing gas sources and guide lines to indicate the route to the exit.<ref name="CoP Scientific" /><ref name="High risk" /><ref name="Jablonski 2006" />

Night diving can allow the diver to experience a different underwater environment, because many marine animals are nocturnal.<ref name="BSAC" /> Altitude diving, for example in mountain lakes, requires modifications to the decompression schedule because of the reduced atmospheric pressure.<ref name="Jackson 2000" /><ref name="USNDM R6" />

Recreational dive sites

The Blue Hole in Dahab, Egypt, a world-renowned recreational dive site

Main article: Recreational dive sites

The common term for a place at which one may dive is a dive site. As a general rule, professional diving is done where the work needs to be done, and recreational diving is done where conditions are suitable. There are many recorded and publicised recreational dive sites which are known for their convenience, points of interest, and frequently favourable conditions.

Recreational dive sites

• Index of recreational dive sites
• Inland dive sites – Dive sites in bodies of water other than the sea
• Coastal dive sites – Dive sites near a coast of the body of water
• Cave diving
• Coral reef
• Lake
• Muck diving
• Quarry dive sites
• Rocky reef
• Wreck diving

Diver training sites

Diver training facilities for both professional and recreational divers generally use a small range of dive sites which are familiar and convenient, and where conditions are predictable and the environmental risk is relatively low.<ref name="CoP Training" />

• Swimming pool
• Diver training tank
• Confined water
• Open water

Hyperbaric treatment and transport environments

Physiologically and legally a compression in a diving chamber is considered a dive. Various options for hypwrbaric transport and treatment exist, each with its own characteristics, applications and operational procedures.

• Closed bell
• Hyperbaric stretcher
• Hyperbaric lifeboat
• In-water recompression
• Recompression chamber

Environments by confinement

Confinement can influence diver safety and the ability of the diver to perform the required task. Some types of confinement improve safety by limiting the ability of the diver to move into higher risk areas, others limit the ability of the diver to maneuver or to escape to a place of safety in an emergency.

• Confined space
• Confined water. The Queensland government define confined water for recreational diving purposes as "Water which offers pool-like conditions, good visibility, and water which is shallow enough so that all divers can stand up with their heads well clear of the water".<ref name="Qld CoP rec diving" /> Other definitions do not require such shallow depth, but may have a depth restriction.
• Open water
  • Blue-water diving
  • Black-water diving
• Penetration diving, also known as overhead environments
  • Cave diving
  • Cavern diving
  • Culvert
  • Ice diving
  • Intake
    • Penstock
  • Overhang – A topographical feature which is open to one side, but obstructed overhead, and deep enough for a diver to be under the overhang.
  • Restriction – Space through which it is possible for a diver to pass with some difficulty. Section of a cave which is difficult to pass through due to lack of space. A minor restriction is too small for two divers to swim through together, a major restriction requires the diver to remove equipment to fit through.<ref>"Cave diving restrictions". deepdarkdiving.com. Retrieved 19 September 2023.</ref>
  • Sewerage
  • Swim-through – Arch, or short, clear tunnel that has sufficient space to allow a diver to swim through and where the light of the opening at the far end is visible through the hole.
  • Under ships – usually for inspection, maintenance and repair, or incidentally, when diving from one. In some cases the gap between the ship and the bottom or the jetty or dock can be quite small.
  • Wreck diving

Environments by visibility

Visibility in the diving medium directly affects diver safety and the ability to complete useful tasks. In some cases this can be mitigated by technology to improve visibility, but often the task procedures must be modified to suit the capacity of the diver, and the diver must have training and equipment bto deal with emergencies under more difficult circumstances.

• Blue-water diving
• Low visibility diving
  • Silt out
• Night diving
  • Black-water diving

Environments by hazard

Besides the hazards associated with the underwater environment itself, there are a considerable variety of hazard types and risk levels to which a diver may be exposed due to the circumstances of the dive task. Many of these are normally only encountered by professional specialists, and the means of reducing risk to an acceptable level may be complex and expensive.

• Benign water
• Bomb disposal
• Clearance diving
• Combat diving
• Currents – Water flow in a locally consistent direction
• Delta P environments – Environments where a pressure difference causes flow. Usually refers to cases where the flow is likely to entrain and pull the diver into an enclosed space or moving machinery.
  • Intakes from the body of water
  • Outlets
    • Drains
    • Penstock
    • Sluice gate
• Hazmat diving
  • Contaminated water
  • Nuclear diving
  • Sewer diving
• Lifting bag
• Live-boat diving, also known as liveboat diving or live-boating – Diving from a vessel which may have propellers or thrusters in gear during the dive.
• Penetration diving, also known as Overhead diving
• Underwater construction – Industrial construction in an underwater environment
• Underwater demolition

Environments by temperature

The temperature of the diving environment can influence the equipment used by the diver, and the time the diver can be exposed to the environment without excessive risk.

• Diving in hot water – Water that is hot enough to require measures to keep the diver cool.
• Diving in warm water – Water at temperatures where no thermal protection is necessary.
• Diving in cold water – Water where heat loss is a critical hazard. Arbitrarily specified at below 10 °C for some training standards
• Diving in freezing water – Water where surface layers are at or very near freezing point.

Environments by geography

The geographical location of a dive site can have legal or environmental consequences.

• Tropical diving – Diving in tropical waters
• Temperate water diving – Diving in temperate waters
• Polar diving - Diving in polar waters
• Altitude diving
• Cave diving
• Drift diving
• Inland diving
• Reef diving
  • Artificial reef
  • Coral reef
  • Rocky reef
• Inshore diving
• Offshore diving – Diving outside the territorial waters of a country
• Open ocean diving

Environments by topography

• Blue-water diving
• Cave
• Culvert
• Dam – Barrier that stops or restricts the flow of surface or underground streams
• Deep diving
• Flooded mine
• Flooded quarries
• Ice diving
• Lake
• Mid-water – Away from any fixed solid reference points.
• Muck diving
• Reef
  • Artificial reef
  • Coral reef
  • Rocky reef
• River
• Reservoir
• Sump
  • Sump (cave)
• Tunnel
• Wall diving
• Water tank

Environments by depth zone

See also: Deep diving

A technical diver using a closed circuit rebreather with open circuit bailout cylinders returns from a 600-foot (180 m) dive.

The recreational diving depth limit set by the EN 14153-2 / ISO 24801-2 level 2 "Autonomous Diver " standard is 20 metres (66 ft).<ref name="EUF" /> The recommended depth limit for more extensively trained recreational divers ranges from 30 metres (98 ft) for PADI divers,<ref name=padi1 /> (this is the depth at which nitrogen narcosis symptoms generally begin to be noticeable in adults), to 40 metres (130 ft) specified by Recreational Scuba Training Council,<ref name=padi1 /> 50 metres (160 ft) for divers of the British Sub-Aqua Club and Sub-Aqua Association breathing air,<ref name="Cole 2008" /> and 60 metres (200 ft) for teams of 2 to 3 French Level 3 recreational divers, breathing air.<ref name="Code du sport" />

For technical divers, the recommended maximum depths are greater on the understanding that they will use less narcotic gas mixtures. 100 metres (330 ft) is the maximum depth authorised for divers who have completed Trimix Diver certification with IANTD<ref name=IANTD /> or Advanced Trimix Diver certification with TDI.<ref name=TDI /> 332 metres (1,089 ft) is the world record depth on scuba (2014).<ref name="GuinnessGabr" /> Commercial divers using saturation techniques and heliox breathing gases routinely exceed 100 metres (330 ft), but they are also limited by physiological constraints. Comex Hydra 8 experimental dives reached a record open water depth of 534 metres (1,752 ft) in 1988.<ref name="Hydra 8" /> Atmospheric pressure diving suits are mainly constrained by the technology of the articulation seals, and a US Navy diver has dived to 610 metres (2,000 ft) in one.<ref name="Depth record" /><ref name="Nuytco" />

From an oceanographic viewpoint:

• Shallow water, defined as between the surf-zone and the coast
• Intermediate water, defined as between the surf zone and wave base (where the waves just interact with the bottom and no more, usually about 80 m water depth with 10 second swells). The seafloor beneath intermediate water is termed the shoreface and is the zone where the seafloor slows down the swells by friction, so that the surf ends up being lower than it otherwise would be.
• Deep water, defined as deeper than wave base: i.e. too deep for waves to interact with the seafloor.

Recreational divers will usually dive in the shallow to intermediate marine environment. Technical and commercial divers may venture into the deep water environment.

Environments by professional activity

See also: Professional diving

• Aquaculture
• Aquarium
• Archaeological sites
• Clearance diving
• Deep sea mining, also known as Underwater mining
• Demolition
• Dry dock
• Fish farms
• Forensic investigation
• Inspection
• Marine salvage
• Military
• Mooring
  • Single buoy mooring, also known as Single point mooring
• Nuclear power plant
• Oil rig
  • Oil platform, also known as Production platform
• Public safety diving
• Science – Systematic endeavor for gaining knowledge
• Search and rescue
• Sewage treatment
• Ships husbandry
• Submarine pipeline
• Surveying
• Training
• Underwater construction, also known as Civil engineering – Industrial construction in an underwater environment
• Wellhead

Diving medium

• Underwater environment – Aquatic or submarine environment
  • Fresh water
    • Potable water
  • Brackish water
  • Seawater
  • Brine
  • Contaminated water
    • Sewage
• Drilling fluid, also known as drilling mud
• Petroleum, also known as crude oil
• Fuel oil