100 metres — the deepest open-circuit certification there is. Hypoxic high-helium trimix and extended decompression, opening Malta's deep wrecks: HMS Southwold at around 75m and ORP Kujawiak close to 100m. If you've got the experience and you're ready for it, we'll get there together.
Advanced Trimix is the pinnacle of open-circuit technical diving — hypoxic high-helium blends and dives to a maximum of 100 metres, the deepest depth any open-circuit certification will take you. That opens up wrecks most divers never see, and Malta has some of the most extraordinary deep wrecks in the world.
ORP Kujawiak sits close to the 100-metre mark off Malta — a Polish-manned Hunt-class destroyer that struck a mine in 1942. At nearly 100m she sits right at the edge of what open-circuit diving allows, and reaching her properly is exactly what this certification is for. HMS Southwold, at around 75 metres, is the other great Advanced Trimix objective — beyond the reach of standard 60m Trimix, but well within range here, with enough bottom time to actually explore her.
The course runs 7–10 days because it needs to. We're talking about high-helium blends to as deep as 100 metres, with extended decompression obligations that can run well over an hour. The planning alone for these dives takes time to get right. Even experienced divers are often surprised by the complexity of a proper deep trimix dive plan — the number of cylinders, the gas switches, the contingencies within contingencies. We go through all of it methodically.
Malta's very deepest wrecks lie further still — HMS Olympus, a British T-class submarine, rests at 115–130 metres, and HMS Russell at over 110 metres. These sit beyond the 100-metre limit of open-circuit diving: they're the realm of closed-circuit and dedicated exploration. What Advanced Trimix gives you is everything down to 100 metres — and in Malta, that's a remarkable amount of history.
The core principle throughout this course is margin — building conservatism into every dive plan so that your actual operating conditions sit well within your training and capability. Deep trimix diving done well is methodical and deliberate. This course teaches you to approach it that way from the start.
This is a bespoke programme. Dates, duration and specific dive sites are planned around your experience level and what you want to achieve. Contact me directly and we'll have a proper conversation about it.
Advanced Trimix takes you to 100 metres — as deep as open-circuit diving goes. Almost everything Malta has to offer is now within reach, and Malta has more than most places. From a career perspective it's also the technical diving foundation for the deepest levels of TDI Technical Instructor training. But honestly, the reason people do this course is wrecks like ORP Kujawiak and HMS Southwold — and that's reason enough.