A technical diver handling decompression stage cylinders during a dive

Photo by Teemu Virtanen · CC BY-SA 3.0

OC Tech (40m)PADI TecRec

Tec 40 Trimix

Official course standards ↗Last updated September 7, 2026

Extend your Tec 40 skills into deeper depths by introducing trimix (3-component) breathing gases that reduce nitrogen narcosis. This course teaches trimix blending theory, hypoxic and normoxic trimix calculations, and decompression planning with trimix bailouts. You'll learn how custom gas blends extend your bottom time and comfort at depth while managing oxygen toxicity and hypoxia risks. Tec 40 Trimix qualifies you for deeper wreck and cave technical diving where nitrogen narcosis becomes a significant limiting factor.

Centres that teach this course

1 dive centre in the directory publish a price for this exact certification, checked Sep 2026. Each centre's own wording is shown beneath its name. Ranges cover whole-course prices only — where a centre charges per day or per dive, its rate is listed separately below, since a daily figure is not comparable with a course total.

One centre publishes a price in Euro.

Same training under a different agency

17 centres

A separate set of centres, teaching Helitrox / Advanced Recreational Trimix under a different agency. These are not the same certification — the standards and the card differ — but they cover the same depth and scope, which is why centres price them alike. Every row here names whose rating it is, and none of them is counted above.

€560 – €1,200across 12 centres pricing in Eurofrom ≈ $626
THB 25,000 – THB 35,000across 5 centres pricing in Thai Bahtfrom ≈ $743
Priced per day or per dive in US Dollar — see below.

    Charged by the day or dive rather than as a course price:

    • Elite Divers InternationalMexico
      Advanced Recreational Trimix (Helitrox) DiverIANTD
      $275/day→ $1,100 for the 4-day minimum
      $275
      per day
    • Third Dimension DivingMexico
      Advanced Recreational Trimix Diver (Helitrox)IANTD
      $295/day→ $1,180 for the 4-day minimum
      $295
      per day
    • Cave AdventurersUnited States
      HelitroxTDI
      Private class$450/day→ $1,350 for the 3-day minimum
      Group class$350/day→ $1,050 for the 3-day minimum each
      $450
      per day
    IDR 18,000,000 – IDR 20,700,000across 2 centres pricing in Indonesian Rupiahfrom ≈ $1,005
    • Bali Dive TrekIndonesia
      IANTD Advanced Recreational TrimixIANTD
      IDR 20,700,000
      total
    • Sulawesi Dive TrekIndonesia
      Advanced Recreational TrimixIANTD
      IDR 18,000,000
      total
    One centre publishes a price in Philippine Peso.
    • Tech AsiaPhilippines
      TDI HelitroxTDI
      ₱28,950
      total

    Same tier, agency not stated

    1 centre

    These centres publish a price for Helitrox / Advanced Recreational Trimix, but their own wording does not say which agency's certification it buys — many teach several and name the card only once you enquire, and some price one course for either agency. The figure is comparable; the certification is not identified, so we do not guess at one.

    Priced per day or per dive in US Dollar — see below.

      Charged by the day or dive rather than as a course price:

      • Darkside DiversMexico
        Helitrox Diver
        $250/day→ $1,000 for the 4-day minimum
        $250
        per day

      These prices are not like-for-like. Two centres can charge very differently for the same certification because they include different things. One price may cover twinsets, stages, deco gas and cylinder rental for every training dive, a dedicated classroom for the theory, boat or transport to the site, and the agency's registration and materials; another may be tuition only, with all of that charged separately — or the other way round, with a centre bundling in extras the first leaves out. Class size, whether the course is one-to-one, and how many days are allowed for it move the figure too. Check what each centre's price includes before comparing them, and confirm with the centre before booking.

      Consumables are usually extra. Sorb, helium, O₂ and other fills, park and cenote fees, certification fees and rental are commonly charged on top.

      Packages combining several certifications, upgrades from an existing one, and open-ended day rates are excluded — none of them is the standalone price of this course, and including them would move the figures away from what a new student can actually book.

      Prerequisites

      PADI Tec 40 Diver (or entry prerequisites for combined Tec 40/Tec 40 Trimix course), minimum 30 logged dives with at least 10 on air/nitrox to 40m, at least 18 years old.

      Standards

      What a diver must demonstrate to pass this course — not always published by the certifying agency.

      Successful demonstration of trimix blending and analysis, hypoxic and normoxic trimix calculations, decompression planning with trimix gases, narcosis reduction strategies, and execution of technical dives to 40m/130ft using custom trimix blends.

      No instructors or dive centres found offering this course.

      We're still building out the directory country by country, so this list isn't every instructor or dive centre teaching it in the world — more locations are coming soon.

      Common questions about PADI TecRec Tec 40 Trimix

      How much does PADI TecRec Tec 40 Trimix cost?

      One centre in the TecDiveTools directory publishes a whole-course price for PADI TecRec Tec 40 Trimix: Atlantis Diving Centre Gozo, at €550. Prices differ mainly in what they include, so compare the inclusions before comparing the numbers. Prices were last checked in September 2026.

      What are the prerequisites for PADI TecRec Tec 40 Trimix?

      PADI TecRec's standards require: PADI Tec 40 Diver (or entry prerequisites for combined Tec 40/Tec 40 Trimix course), minimum 30 logged dives with at least 10 on air/nitrox to 40m, at least 18 years old.

      What is the minimum age for PADI TecRec Tec 40 Trimix?

      PADI TecRec's standards state: At least 18 years old.

      How many dives do I need before starting PADI TecRec Tec 40 Trimix?

      PADI TecRec's standards state: Minimum 30 logged dives with at least 10 on air/nitrox to 40m.

      What does PADI TecRec Tec 40 Trimix training involve?

      According to PADI TecRec's published standards: Successful demonstration of trimix blending and analysis, hypoxic and normoxic trimix calculations, decompression planning with trimix gases, narcosis reduction strategies, and execution of technical dives to 40m/130ft using custom trimix blends.

      What is the equivalent of PADI TecRec Tec 40 Trimix in other agencies?

      At the same tier in TecDiveTools' cross-agency comparison: IANTD Advanced Recreational Trimix Diver, SSI XR Extended Range Trimix and TDI Helitrox. They cover comparable training, but each agency sets its own standards, depth limits and certification card, so they are comparable rather than interchangeable — check which one your next course accepts.

      IANTD Advanced Recreational Trimix DiverSSI XR Extended Range TrimixTDI Helitrox

      Does the price of PADI TecRec Tec 40 Trimix include gas and equipment?

      Not always — it varies by centre. Helium, certification fees, equipment rental and boat or site fees are commonly charged on top of the course price. Each centre's price list on TecDiveTools shows what it notes as included.

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