The bridge between recreational and technical diving
Tec 40 is the first PADI TecRec technical diving course for experienced recreational divers. It bridges no-stop diving and technical decompression diving: you learn to plan and make dives to 40 metres with limited decompression of no more than 10 minutes. For decompression you use a single cylinder of nitrox with up to 50% oxygen (EANx50) to make the decompression more conservative.
Tec 40 is the first part of the Tec Deep programme: your training credits toward the Tec 45 and Tec 50 courses.
What you learn
- Decompression theory: Dalton's and Henry's laws, nitrogen uptake and elimination, decompression obligation and the idea of limited decompression.
- Gas planning: gas consumption (SAC/RMV) calculations, the rule of thirds, reserves and emergency gas needs, matching gas within the team.
- Equipment: double cylinders with an isolation manifold (backmount) or sidemount, wing, independent regulators, decompression computer, surface marker buoy and reel. You assemble the equipment from scratch.
- Planning: a decompression dive plan with tables or decompression software.
- Team: the technical diving mindset, team roles, the pre-dive briefing.
How the course runs
After theory and practical sessions you make four training dives in open water. You work on horizontal trim and buoyancy so you can hold your depth precisely on decompression stops, as well as valve drills, regulator switches, deploying a surface marker buoy and gas switching.
A lot of attention goes to emergencies: gas loss, regulator failure, sharing gas with a team member and a controlled end to the dive. The course focuses on a correct basic configuration, tidy equipment handling and decision-making under stress.
Frequently asked questions
Is Tec 40 already technical diving?
Yes, it is the first level of technical diving. You dive with technical equipment and plan decompression dives, but decompression is limited to 10 minutes and depth to 40 m.
What equipment will I train with?
Double cylinders (backmount) or a sidemount configuration, a wing, independent regulators and a decompression computer. We provide the course equipment.
Can I continue to Tec 45 after Tec 40?
Yes. Tec 40 is the first part of the Tec Deep programme and its training credits toward Tec 45 and Tec 50. For Tec 45 you also need a PADI Rescue Diver certificate and 50 logged dives.
How long does the course take?
5–7 days: theory, practical sessions and four open-water dives. We agree the schedule with you.