Technical Diving Essentials


Technical diving, also referred to as tech diving or tec diving, is any type of diving outside of recreational limits. It developed from a form of cave diving and typically involves dives that are beyond 40 meters (131 feet) deep or extend in an enclosed environment beyond 40 meters from the entry point.

Technical diving involves advanced dive skills, technical diving gear, specialist training, decompression stops and the use of gas mixtures (depending on the type of technical dive).


Technical divers have the freedom to explore dive sites that recreational divers cannot reach and experience places that few people ever get to visit, such as deep shipwrecks that are otherwise inaccessible. It is a great way to explore new dive sites and learn a challenging type of diving.


Technical diving has gained great popularity in recent years and there are top technical dives around the world just waiting to be explored. Liveaboard vessels offer technical diving support and the opportunity to reach more remote technical dive sites.


Truk Lagoon is known for having more than 48 wreck diving sites and its waters are up to 100 meters (328 feet) deep. It is one of the best places for wreck diving and offers great opportunities for technical diving amongst World War II wrecks. It is particularly good for new technical divers, as the lagoon waters are consistently calm and sheltered.

Many of the wrecks are within recreational depth limits and there are around 15 wrecks at 40 to 60 meters (131 to 196 feet) deep. The San Francisco Maru, lying at a depth of around 63 meters (206 feet) is a favourite amongst technical divers because of its four cargo holds containing aircraft bombs, artillery shells, tanker trucks, a flatbed truck, and torpedo warheads. The Fujikawa Maru is another popular wreck, lying at around 36 meters (120 feet) deep, and is a Japanese Navy passenger and cargo ship. Her hold contains three aircraft and she also contains numerous World War II artefacts.

Scuba diving at Truk Lagoon is a fantastic experience and the wrecks are encrusted with corals and populated with plentiful fish life. Barracuda, turtles, groupers and pelagic sharks are all seen at Truk.

The SS Thorfinn liveaboard is geared up for technical divers and has two special diving packages. The Rebreather Plan includes daily diving, free rebreather cylinder hire and fills, free sofnolime, and extended deep schedules with an experienced guide. Helium is also available. The Truk Tek Unlimited package includes daily diving, the use of side-mount cylinders, manifold twins, stage cylinders and pony bottles, plus free cylinder fills and custom dive schedules.


Honduras liveaboard diving offers the chance to experience sheer wall dives, canyons, trenches, and reefs around Roatan and Utila, and is gaining a reputation as a technical diving destination.

Utila, in the Bay Islands, has deep walls and caves to explore on the north side, with dive depths of 45 to 80 meters (147 to 262 feet). Some of the caves on the north side have stalactites and plenty of visiting pelagic species such as a barracuda and marlin. The eastern and southern sides of Utila have seamounts and pinnacles at depths of 40 to 80 meters (131 to 262 feet) and challenging current dives. There are numerous technical dive sites around Utila, including Whale Rock where divers can ascend up the ‘whale’s head’, swim through its eye at 45 meters (150 feet) depth and through its ‘blowhole’ at 39 meters (130 feet) depth. This dive site has colourful corals and sponges plus shoals of jacks, snappers, glassy sweepers and wrasse.

The Cayman Trench, off Roatan, has walls and crevices to explore at up to 60 meters (196 feet) deep. The trench is home to black corals and is known for whale shark encounters.

The Roatan Aggressor offers dive safaris to experience the best of Roatan diving, Utila and Cayo Cochinos.


Puerto Galera is a top muck diving destination and also offers some of the best Philippines technical diving. It is suitable for both new and experienced technical divers and has a variety of technical dive sites to explore.

The Verde Island passage, covering 1.14 million hectares, has numerous deep dives including wrecks, walls and drop-offs. The currents in the passage can be strong and are ideal for drift diving, with excellent water visibility.

The east of Verde Island has two great technical dives. The Pinnacle dive site descends to 60 meters (196 feet) deep and is a coral dive with large pelagic life. The Wall dive site disappears into the depths to over 70 meters (229 feet) and offers gorgonians, corals and schools of reef fish. It is an ideal destination for combining technical diving with searching for tiny critters in the deep, including frogfish, Bobbitt worms and mimic octopus.

There are a number of Philippines liveaboard diving vessels to choose from to make the most of this tropical paradise. The budget-friendly M/V Dolphin liveaboard offers Puerto Galera safaris and has technical diving support. 


Dahab is an iconic technical diving destination, thanks to the infamous Blue Hole dive site. This underwater sinkhole reaches depths of over 100 meters (328 feet) and has a famous arch at around 55 meters (180 feet) that connects the Blue Hole to the Red Sea. The arch plummets beyond the reef wall to over 1000 meters (3280 feet) deep. It is a great area for technical diver training as there are minimal currents and plenty of deep dive sites to choose from.

The Canyon at Dahab is a popular dive site and is a natural reef crack that descends to 54 meters (177 feet) and has walls up to 20 meters (65 feet) high. Neptune’s Chair sits below the Canyon at 70 to 80 meters (229 to 262 feet) deep.

Sharm El Sheikh liveaboard diving is a popular dive choice to explore the well-known Straits of Tiran and Ras Mohammed National Park. There are multiple technical diving sites in the area, including Thomas Canyon at Thomas Reef. Thomas Reef is a colourful dive site with plentiful reef fish and coral life. Thomas Canyon drops to a maximum depth of 92 meters (301 feet), has archways along its length, a swim through at 65 meters (213 feet) and a lip at 40 meters (131 feet) deep. 

Elphinstone liveaboards take divers to some of the best Red Sea diving, just north of Marsa Alam. The well-known Elphinstone Arch is a popular technical dive at 60 meters (196 feet) and consists of a tunnel passing between two walls. The walls are covered in ledges and are home to corals, trigger fish, napoleon wrasse and more. Hammerhead sharks and whale sharks are sometimes seen there as well. The SS Maidan at Marsa Alam is a 1912 steamer, used to transport troops in World War I, and is visited by just a few technical divers each year. It is one of Egypt’s lesser-known wrecks and sits at a depth of 120 meters (394 feet).

There are numerous Egypt liveaboard vessels to choose from, including the following that offer technical diver support:

Aphrodite | Coral Dreams | Excellence | Emperor Elite | Heaven Saphir | Nouran | Oceanos | Okeanos Xplorer | Tala


A Florida Islands liveaboard is one of the best ways to explore the stunning Solomon Islands, which is a great technical diving destination. The dive sites around the Florida Islands are diverse and there are so many wrecks the area is nicknamed the ‘Iron Bottomed Sound’. The seabed is littered with at least 200 varieties of watercraft and over 600 aircraft from World War II. Some of the wrecks are still intact and the volcanic activity in the area has resulted in interesting landscapes such as lava tubes and caves.

There are plenty of options for technical divers, including the USS Aaron Ward. This wreck is considered one of the world’s top wreck dives and lies at 60 to 70 meters (196 to 229 feet). In addition to the array of wrecks to explore, some divers have even reported seeing pilot whales in the area whilst sailing.

The Solomons PNG Master liveaboard offers Solomon Islands dive safaris and has technical diver support.


Truk Lagoon diving is possible all year and the currents are consistently low.

Honduras diving is also possible all year, though water visibility can fall slightly during the rainy season of October to January.

The Philippines diving season is all year but there are distinct dive seasons that affect dive conditions. The dry season of March to June generally has the best visibility. That being said, The M/V Dolphin focuses on Puerto Galera safaris from June to February each year during the transition season and has technical diving support.

Egypt diving is available all year, as is Solomon Islands diving. The Solomon Islands experience a minimal rainy season from November to April, but it is not monsoonal.


A variety of marine life and unusual landscapes can be seen whilst technical diving. One of the great things about technical diving is the variety of available destinations, providing the chance to see diverse marine life from reef species through to large pelagics and plentiful macro life. There is information about marine life highlights at different destinations in the destination guide above.


The technical diving depth limits depend on the technical diving course the student has completed and is certified to dive to. There are various technical diving courses available which certify divers to depths ranging from 40 to 100 meters (131 to 328 feet).


Divers sometimes exceed the standard technical diving depth limits, in exceptional circumstances and with appropriate experience and supervision. Ahmed Gabr set the world record for the deepest male scuba dive in 2014, descending to 332.25 meters (1090 feet) in 14 minutes off the coast of Dahab, Egypt. He used 92 tanks and spent more than 14 hours underwater.


The prerequisites for different technical diving courses vary, but the entry level courses usually require a diver to be an advanced diver with Enriched Air certification and to be at least 18 years old, with a minimum of 20 to 30 dives. Technical diving courses are offered by a range of dive training agencies.

These include:

  • SSI’s Extended Range suite of technical diving courses
  • TDI’s Technical Diver courses
  • PADI’s Technical Diving courses


The diving gear needed for technical dives is specialised and varies according to the type of diving being done. Technical dive gear can include that used for cave diving, sidemount diving, ice diving, deep diving beyond 40 meters (131 feet), deep penetration wreck diving, rebreather diving and more.

Technical divers often carry additional tanks and can need to carry backup systems for everything from dive computers to masks, regulators and air sources.


Technical divers need a broad range of specific skills including advanced buoyancy control, gas planning and management, gear configuration and dealing with dive problems at extreme depths.


The main hazards associated with technical diving are the deep dive depths, if doing deep technical diving, and the management of gases. Other hazards include the inability to ascend directly due to the need for a decompression stop or a physical barrier such as a cave ceiling, plus limited visibility in low light conditions at depth or within an enclosed area.

All of these hazards can be managed with appropriate training, knowledge and skills, plus by using suitable equipment and procedures. All of which can help ensure safe and enjoyable technical diving at some of the world’s best dive sites.