Open circuit courses

STDA proposes scuba diving courses with 3 recreational levels (from beginners to advanced) and 3 for decompression diving. For divers that come from oher agencies that want to go on with STDA advanced diving and don't know the hogartian configuration and the DIR approach, the first course is the 'Fundamentals - Intro to Tech'.

  • R1 - Open Water Diver
  • R2 - Advanced Open Water Diver
  • R2 Deep - (includes the Rescue Module)
  • EANx Diver - (R1 & R2 course sections)
  • Fundamentals - Intro to Tech
  • T 1 - Trimix Decompression 50 mts
  • T 2 - Trimix decompression 60 mts
  • T 3 - Trimix Decompression 80 mts

For all the courses it's possible to attend the theory sessions through the web. In this way you can use your time at the best. Same thing if you want to come in Italy to attend your courses. You can do the theory lessons before your coming. Contact us at:


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T3 – decompression Tri-mix 80 meters course (STDA™)


The 'T 3' course aims to complete the training started with the 'T 2' expanding the theoretical and practical knowledge and experience, to dive at a maximum depth of 80 meters, using Tri-mix and multiple decompression mixtures. The structure of the program is the same of the previous courses: theory, confined water sessions and open water dives. The 'T 3' program is mainly focused on decompression theory and procedures, to extend the range of the dives. With the positively conclusion of the course the diver will be able to plan and dive till 80 meters depth.

STDA fixes the 80mts depth as limit for the OC diving and considers rebreathers the logical diving equipment for deep dives, just below 60 mts depth.


  • be certified 'T 2' or equivalent
  • medical certificate not older than one year; recommended PFO examination (Patent foramen ovale); non smoker
  • minimum age: 21 years old
  • documented experience of at least 100 dives, 40 with decompression

Before the course start, the instructor could ask to do a open circuit dive to evaluate the level of training of the candidate.

Program and duration of the course with 3 students

minimum days: 5

theory: minimum 12 hours

Theory sessions: 5 - ratio instr/student: 1/4

Final assessment: quizzes with multiple choice

Maximum percentage of allowed wrong answer: 20%

Exceeding the maximum allowable percentage leads  to the repetition of the quiz not before than 2 days

Shallow water sessions: minimum 1 - ratio instr/student: 1/4

Open water dives: minimum 2 with a cumulated run time of minimum 180 minutes - ratio instr/student: 1/2

The maximum time for completion of the course: 6 months that if exceeded, the course must be repeated entirely

Certification limits

  • Max depth: 80 meters with mandatory tanks with adequate mixtures and volumes (liters of the mix)
  • Max pO2, Allowed for bottom mix: 1,2 ata
  • Max pO2, in decompression: 1,6 ata
  • Allowed bottom mixes: Tri-Mix - Max fHe 0,70 - 0,10≤ fO2≤ 0,13
  • Allowed decompression mixes: Triox 35/30 – Triox 50/20, EAN50 , Oxygen;
  • For all the mixes fO2 range: +/-0,01


1400€ for training (manual + theory in classroom/web on-line, quiz, cw sessions and dives)

NOT included: mix, , instructor 'room and board' for other locations, boats if needed and extra days for training or delays due to adverse weather conditions.

Extra training day cost: 200€/day

In case of 2 or more students and x-over, please contact the instructor for a quotation.



Marco Valenti
38122 Trento (TN) - Italy
t. +39 347 5041939
Copyright © 2024 Marco Valenti