The next day was technical sidemount. This means that we added our deco 50 and 100 percent oxygen tanks on either side. This can increase your profile underwater. It is important that you keep your tanks as small as possible. The clips can be found on each side. As your tanks become buoyant, you will adjust your tank position to fit the second clip. Here, the goal is to be as efficient as possible. Each few minutes, you switch your breathing between the tanks. By doing this, the pressure in each of the tanks will decrease at roughly the exact same rate. In the event that a tank or regulator fails you will still be able to breathe. It is important to gain experience with any new thing. I spent the next few nights doing deco dives with the sidemount rig. I was buddied with Evolution coowner David Joyce who is a very experienced Tec diver as well as a Trimix instructor. One dive saw us visit the Japanese Mogami Japanese Mogami sank at 164 feet. It was here that I was seduced by old gas masks and uniforms as well as a few bones.
TDI is an American tech diving organization that was found in 1994 and has instructors all around the world. The prerequisite to start technical diving with a TDI instructor are the Advanced Open Water certification of any organization, Nitrox certified and a minimum of 25 dives. The first technical diving courses are TDI Sidemount (within No deco limits) and Advanced Nitrox and Decompression Procedures allowing to dive to 45m, using oxygen mixes up to 100% of oxygen and doing staged decompression stops. The course contents include theory, pool work, and a minimum of 6 dives depending on your level of comfort in the water in order to be able to complete all open water requirements safely and efficiently and to understand planning and preparation of a technical dive.
