Until recently, Nitrox diving was considered technical, but this is no longer the case. An Open water diver level allows you to have the experience of Nitrox diving or to be trained for Nitrox Specialty certification (EAN Diver).
So what is Tec? Basically it's not referring to diving 100m deep or carrying many tanks on your harness. Many systems define Tec as diving beyond recreational limits, i.e.:
- diving with multiple gas mixes;
- diving with exceeded bottom time (so that level of nitrogen saturation is higher and direct acsent to the surface is not a safe option anymore);
- diving deeper then 40m;
- diving in ovehead environments.
These points are reflecting real Tec training levels:
- first of all it's a deeper studies of equipment and diving techniques (TDI Intro To Tec);
- Certification for Nitrox < 40% Oxygen diving (TDI Nitrox - Analog to PADI EAN Diver);
- Certification for Nitrox > 40% Oxygen diving (TDI Advanced Nitrox) - 40 m is a depth limit;
- Diving deeper then 40m - studies of decompression procedures for safe ascents after higher nitrogen exposure (TDI Decompression Procedures) - 45m depth limit;
- Extended range diving - with air as a bottom gas and decompression Nitrox stages - depth limit 55m;
- Trimix diving (60 m depth limit);
- Advanced Trimix diving (100m depth limit).
So most of your tec dives will be performed in ranges of 30-45 (55) meters, and not the depth is a question - but how many things you will be able to observe staying in place longer - but within your safe diving plan.
How it works in real environment? Thistlegorm wreck is a perfect illustration (max depth - 30m, first deck at 15m, holds at 20-25m). Diving this wreck can be a "penguin diving day" (short deep dives with the poor time inside the holds) or few long enjoyable dives with full wreck observation.
Improve your dives - join Tec community! Check Tec courses with XDI here.