What is technical diving?
If your diving regularly, your diving may get to a point where you would like to stay down longer to see deeper things. By deeper, I mean deeper than recreational limits. If your diving passion brings you to this point, that’s when you may start to explore what technical diving is. Technical diving is for diving deeper than recreational limits and exceeding standard recreational none decompression limits ( NDL). Technical diving requires lots of training and more equipment and potentially increases danger, but it is a lot of fun. However, it is not for everyone.
Agencies–GUE INTD PADI tech TDI, Different philosophy
Not all agencies Offer Technical dive certification. The ones that do all have a minimum number of dives that must be completed and prerequisite dive certifications before starting the training. For example, PADI Requires A PADI Advanced Open Water Diver, PADI Enriched Air Diver with at least ten dives using enriched air deeper than 18 metres/60 feet, A PADI Deep Diver or proof of at least ten dives to 30 metres/100 feet. At least 18 years old and have a minimum of 30 logged dives. NAUI You must also be a certified NAUI Scuba Diver and NAUI EANx Diver (or their equivalents) and have at least 25 logged dives with at least 10 EANx dives. Prerequisites vary for each technical training program. The best way to learn more about technical diving would be to take an INTRO to tech or discover tech courses if available in your area. Better yet, try to meet people who are already diving technically. That way, you can pick their brains as to why they got involved in technical diving and who are the best instructors locally, if any. All agencies have a different philosophy about diving. Some agencies’ philosophies use what is proven to be the optimal configuration. Other agencies aren’t as ridged with equipment configurations and recommend using what works for you. These are just some of the differences between agencies and why meeting and talking to tech divers may save you some time, but hopefully, this article can point you in the right direction.
Dive theory
Fundamentally what I feel makes technical diving different than recreational diving is the actual application of diver theory. A dominant Idea/practice in technical diving is dive decompressions. This is where one must maintain specific depths for a duration of time on a particular mix of gas concentrations before surfacing. Put another way. Technical divers have an artificial ceiling on all their dives requiring them to complete planned decompression stops before surfacing. For example, breathing 100% oxygen at 10ft for 25 min. The Reason, a Technical diver, breathes different concentrations of oxygen, nitrogen, and maybe Helium at different depths is because of the principles of Decompression theory. General Decompression theory states that;
-when a diver is at depth, the elevated inert gas pressure in the breathing gas will dissolve through the lungs into the bloodstream and body tissue in accordance with Henery’s Law.
– Technical diving trains a diver to follow technical dive tables that have calculated nitrogen, oxygen, and helium bubble size accumulation in different tissues in your body. (blood, organ tissue, bone tissue)
-By applying this information, a technical diver can choose the right concentration of gas to breathe and at what depth to breathe the gas that’ll enable them to have the lowest decompression times for their dive plan.
Applying this knowledge, in conjunction with the different equipment and the new skills, enables the technical diver to go deeper than a recreational diver and stay down longer than a recreational diver. So inherently, the skills and Depth and conditions do have increased danger, and no other course will you hear them talk about you risking your life or losing your life more than when you start your technical diving training. So it’s not taken lightly at any point in the training.
Skills required
These are listed as some of the foundational technical diving skills according to the NAUI intro to tech.
Mask skills
Clear a mask of water with a single breath. With a mask removed, share air with a teammate while swimming at least a hundred feet, then replace and clear the mask in less than 5 seconds.
Buoyancy and trim
Be able to descend to depth slowly and hover without contacting the bottom.
Use breathing to maintain trim and control buoyancy while hovering off the bottom.
Hover for 2 minutes horizontally without changing depths more than 2 ft (61cm). While hovering in a horizontal position, pass the primary regulator to an out of air diver without changing depths by more than 2 ft (61cm)
Propulsion
Demonstrate proper kicking technique by using both flutter and frog kicks and be able to alter between these two.
Demonstrate the ability to travel across a silt bottom in full technical diving Gear with a minimum silt Stirrup or none at all.
While hovering horizontally, perform 360-degree turns in each direction using only the legs.
While hovering horizontally, be able to turn in any direction and back up slowly using only the legs.
Gas management
Demonstrate ability to estimate when two-thirds of the Breathing supply is depleted.
Be familiar with and execute rules of thirds for gas management and adjust for dissimilar tanks in various conditions while in the water.
Out of gas drills
Demonstrate proper Long hose use and deployment while maintaining proper buoyancy and body position while at the same time sharing gas with another diver. This is done both while swimming single file and ascending to the surface. This is the same as an S-drill just performed during a dive not at the start.
Line drills
Demonstrate proper line technique and tie-offs.
Lift bag for marker deployment.
Demonstrate two different techniques to deploy lift bag marker from Depth safely.
Team contact actively participates in the planning and executing of a comprehensive dive plan while ensuring that all involved are comfortable and capable.
Safety drills
Safety is paramount in technical diving, and there should be a few rescue scenarios as part of your training. These scenarios will be performed in the most realistic manner possible, you may feel challenged performing your new skills during these simulated scenarios. This will only better prepare you for the technical diving you are going to do. Because safety becomes part of your dive culture as you progress through your technical training, you will constantly practice these fundamental safety skills. One of those primary safety skills is an S Drill or Safety Drill. The S-drill was performed with our buddies at the start of every dive once I took my Intro to Tech course. At the beginning of every dive, we perform an S-drill myself, and my buddy team will descend to about 10ft of water to find natural buoyancy and horizontal trim. At his point, one diver will signal out of air to their other buddy. My buddy provided me air from their long hose while they switched to their necklace regulator. After 1-2 breaths, ill return the regulator to my buddy. Once they store their long hose properly, the whole drill is done in reverse. My buddy gives me the out of air signal, and I deploy my long hose for them to breathe from, and I switch to my backup/neckless regulator. We perform this at the start of every dive and a bubble check. That way, you both know that you will provide each other with air practically and efficiently with no hesitation or explanation during any dive. There are several rescue scenarios in which you will be asked to perform all parts of your technical training. Expect to do a buddy air sharing situation where you will be swimming a few hundred feet just breathing from your buddy’s long hose.
Another safety procedure that any student or technical diver may be required to perform is a missing diver search procedure. Practicing these skills become fundamental for the technical diver. These skills must always be fresh, and there is no hesitation when these procedures are needed. Because of my commitment to the diving lifestyle and my want to constantly improve my diving, it is very common for me to go on local dives with my buddies just to practice skills repeatedly. The practise may not make perfect, but it will make an improvement.
Valve drills
This skill requires a diver to demonstrate the ability to efficiently use their tank manifold in the case of a primary failure to any of your hoses or regulator. A diver must be able to close the Isolator valve on their tank manifold Isolateing both tanks. this will save you from losing all the air in both tanks in the case of a hose or regulator failure. once the isolator valve is closed a diver must also shut down the tank valve that is causing the failure and loss of air. This skill needs to be executed while in trim and proper buoyancy, with minimal depth fluctuation of no more than 3 feet and within and allotted time. When I first did my Into To Tech class back in 2016 this was the main skill that caused me to fail the class. I found it very challenging to reach my valves my drysuit and undergarment we too tight to allow me the range of motion I needed to do this skill within the requirements to pass.
Decompression drills
After the Intro To Tech level, you will learn the decompression procedures. This is the procedure a technical diver must perform with their buddy to demonstrate what gas they will breathe at depth. Your buddy will verify that you are breathing the suitable or planned gas at the correct depth. Unfortunately, I am not Deco trained, so I can’t speak to this from experience.
Equipment
Technical diving becomes quite equipment intensive and will generally require a completely different setup or equipment configuration than recreational diving. There are a few reasons for this; one, there are additional environmental conditions, more depth and different concentrations of gases being used, and two; a lot more redundancy to increase safety factors.
Harness and backplate
In Technical diving, you will use a harness and backplate to hold you to the rest of your equipment. The backplate is what the tanks and your wing will fix to, and the harness is what you are strapped into. It’s a 3-point harness over your shoulders and a strap through your crotch and around your waist. The three points secure a diver and hold them in the proper position during diving for the most efficiency.
Wing
Wings come in many different styles and weight capacities. The wing will give you buoyancy in the water, comparable to a BCD (Buoyancy Compensator Device) in the recreational world. This is where you will inflate air to hold you in neutral buoyancy in the water. In Technical diving, we like to call them Wings, you may have different sizes of wing depending on your tank configuration. For example, if you go from a hundred cubic foot set of double tanks to a set of 130 cubic foot tanks may require a different sized wing because you may need an additional lift to float with heavier tanks in the water.
Regulators
Generally, in technical diving, you will use the top-quality premium Regulators. You want Regulators that will perform in the most strenuous conditions. Remember, technical diving involves going deep; different salinity conditions and extreme temperatures are just some conditions a regulator must work within. In addition, you will be breathing several different concentrations of gasses with different densities, i.e. oxygen, Nitrogen, and Helium. These are some reasons that only the best Regulators should be used. Your life support air delivery system is not where you should skip on money or function if you are getting into technical diving. Also, technical divers always have redundant regulators. Diving with a set of double tanks and a manifold allows a technical diver to have two first-stage regulators on each tank as a backup in case one fails.
Cylinders or tank
Technical diving uses the same tanks used in recreational diving. The main difference is that the tanks are configured differently than recreational diving. In Technical diving, it is done with double tanks. These are the same types of tanks set up in double. The tanks are joined using tank bands and a manifold that allows you to have two first-stage regulators adding a lot of redundancy to your equipment configurations. There are also Side mount configurations, which are typically only introduced once a diver is exposed to a back-mounted double. Picking the right tank size and make of tank for your body will require a little experience. Different types of scuba sizes and makes have different buoyancy characteristics. For example, the Catalina brand of aluminum 80 cubic foot tanks, which are great tanks, tends to be light on the bottom when empty, and a Luxifer 80 cubic foot tank brand is light at the neck of the tank. That is good to know because if you use Catalina tanks as your double tanks, it will be good for you to anticipate the positive buoyancy on the bottom of the tanks, which will change your trim if you are not aware of it. Knowing all the individual tank buoyancy and density characteristics is good for choosing the suitable tanks for your height and weight. This would be worked through as part of an Intro to tech class.
Lights
Technical divers always have redundancy, they will have one primary canister light that has a burn time usually two to four hours, and we’ll have two small secondary lights on them that are D Cell battery-powered.
Gauge
One big difference for technical divers is they do not use consoles for their gauges: integrated depth gauge and pressure gauge generally and sometimes a compass. Instead, technical divers will have a computer that will be their bottom timer and depth gauge. In addition, they’ll have a Presto pressure gauge on a high-pressure hose coming off their left post and clipped to a D ring on the left side. A technical diver will also have their compass attached to their left arm. This is pretty standardized and Technical diving if you’re following the NAUI GUE configurations.
One Can see that technical diving does have quite different requirements than recreational diving. This affords Comfort and keeps safety paramount. I feel the best setups are tried-and-true and proven to work by the most experienced divers in the technical community.
Finding what works for you to make you the most comfortable within a specific configuration of equipment that is proven is essential. Some of the ridged equipment philosophies come from the idea that if all the divers dive with their gear in the same way. In the “DIR” (Doing It Right) method, if there is an emergency, the supporting/rescue diver will know where the diver’s equipment is, which regulator is attached to which post to provide air or where the diver’s knife is. It should facilitate supporting a rescue diver to just reach for a piece of equipment, saving time and hopefully saving a life.
Costs training commitment to safety
One of the most significant drawbacks to technical diving is the cost. Not only does the training take a lot longer, and one needs to dive more regularly to make the training effective. There’s also a lot more equipment and constant replacement and maintenance of equipment. These are significant barriers to technical diving. However, I highly encourage anyone who wants to expand on their diving and wants to go further deeper and have more fun exploring technical diving. It has a lot of safety margins, primarily because of the skills that it affords a diver.
Extended safety, more places to see and more fun, but it’s not for everyone.
Technical diving may not be for everyone, but it is for some of you, and I highly encourage you if you’re looking to explore. I hope this information answers some of your questions and hopefully spikes some of your curiosity to explore it. Knowing that it’s not for everyone the new E-course, there are five questions that they ask, and I think every diver should ask themselves these:
1. Are you disciplined enough for the rigours of technical diving?
2. Do you have the dedication it takes for this type of diving?
3. Do you have the necessary skill level and Technical Training required?
4. Do you have the in-water experience to begin this type of training?
5. Are you willing to take a new approach to your equipment configuration?
These are highly valuable questions and can save you time and money. If you answer them sincerely, it can unlock your technical diving Journey