What Is Technical SCUBA Diving?
SCUBA diving has so many possibilities. There is so much to learn. For the laid-back easy-going diver, recreational diving is probably all they will ever do. However, some people like the extra challenges that can be offered by SCUBA diving. Technical SCUBA diving offers a wide range of adventures by going beyond the limits of recreational diving for fun or for work purposes. Whichever route you choose, proper SCUBA diving training is essential for safety, especially within the realm of technical diving. Do NOT attempt any form of SCUBA diving without the proper training.
Recreational SCUBA Diving
Most people do what is called recreational SCUBA diving. This is where everyone starts. Recreational diving has well-studied limitations on diving that make individuals safe. The maximum depth for recreational SCUBA diving is 130 feet. The time at each depth is regulated by the recreational dive tables. If you stay within these time limits for each given depth, then you are doing a recreational SCUBA dive.
Technical SCUBA Diving
So what is technical diving? To keep things simple, technical SCUBA diving is anything beyond the recreational dive limits, whether it be time or depth. Decompression stops are required in technical diving whereas they are not in recreational diving.
Almost all technical SCUBA diving requires decompression stops to be made. There are required stops at given depths for certain periods of time where you hang out to help off-gas the nitrogen absorption. If you were to skip decompression stops, the risk of decompression sickness significantly increases.
Recreational Dive Depth
Since the recreational depth limit is 130 feet, anything dove beyond that is technical diving. While you can have wonderful dives and see a lot in shallower depths, sometimes it is useful to have the skills and supplies to go beyond 130 feet. There are wrecks around the world found in deeper waters that can only be explored by these elite few that are trained in technical diving.
At each depth, even if shallower than 130 feet, if the time stayed is past the limits found on the recreational dive planner for the given depth, then that is now a technical dive. Technical divers can stay for a long time at various depths giving them more time to explore.
Technical diving can also include special environments that require advanced training, such as cave diving or penetrating wrecks. These overhead environments require careful planning to be executed properly. You don’t want to get lost inside a cave or wreck and then be running out of gas to breathe! There are classes that offer excellent technical dive training that focus on laying lines and how to dive properly in overhead environments.
Technical Diving Equipment
Technical SCUBA diving may require specialized equipment. If you were to go deep or stay longer in shallower depths, you would at minimum require more gas for the dive.
Some divers carry two tanks while diving, but this is usually the minimum and the number of tanks can be many! This can also include recreational divers. Having two tanks on your back or in side-mount configuration allows for increased gas supply while diving.
Rebreathers are very common in the technical diving community. Rebreathers allow you to recycle and rebreathe your own air. This is a closed circuit system, compared to the open circuit SCUBA system in recreational diving whereby you breathe in gas from your tank and exhale the carbon dioxide into the water. With a rebreather, the system is closed. You breathe in gas from your tank and exhale into a hose that leads to a carbon dioxide scrubber that removes the carbon dioxide and recycles the oxygen back to your tank. The advantage of using a rebreather is greatest in overhead environments where bubbles exhaled into the water might hit the surface and cause debris to rain down on you, thus limiting your visibility.
Another increase in equipment for technical diving is that in most cases, extra tanks (AKA bottles) are often needed. These dive tanks could contain air, nitrox, trimix, or oxygen and are staged on a line that leads to the surface. These tanks are used for decompression stops on the way back up to ensure that you have enough gas supply required to complete the stops.
Staying down longer or going deeper sometimes requires the use of different gases to help reduce the amount of nitrogen absorption and risk of oxygen toxicity.
To help reduce nitrogen absorption, enriched air nitrox can be used. Nitrox is not just popular in technical diving, but also in recreational diving. Nitrox is a gas that has an increased amount of oxygen thereby reducing the amount of nitrogen in the tank allowing you to stay underwater longer. However, there are depth restrictions for nitrox that are dependent on the percent of oxygen in the tank. This is because oxygen can become toxic at depth and cause convulsions underwater which can lead to drowning.
Since nitrox has depth limitations and even the oxygen in regular air tanks can become toxic, technical divers developed a trimix gas that contains oxygen, nitrogen, and helium. Adding helium to the tank allows the reduction of both oxygen and nitrogen in the tank. It can also be used at greater depths. Yes, if you were to hear a SCUBA diver using helium talking through an underwater communication unit then they would sound funny just like on land!
Pure, 100% oxygen is toxic at depth so it is less commonly used in SCUBA diving. However, at very shallow depths, shallower than 15 feet, it could be used for gas supply. Oxygen in the SCUBA diving world is usually only used on the surface to help treat SCUBA diving injuries.
Technical Diving In Summary
Technical diving is not for everyone. Advanced skills and self-awareness are necessary for safety. For the right person, technical diving opens a world of challenges that results in some beautiful, underwater adventures!