TDI Technical Diving Courses in Essex – ESS‑TEK

TDI technical courses delivered by ESS-TEK


TDI Technical Diver training Without Compromise

TDI courses delivered by ESS-TEK —
the dedicated technical training division of Essex Scuba.
Structured, progression-based education for divers ready to move
beyond recreational limits and dive with purpose, control, and precision.

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What Is ESS-TEK?

ESS-TEK exists for divers who want more than recreational limits. We deliver disciplined,
real-world TDI technical diving training built on precision, preparation, and control.

ESS-TEK is where technical divers are built — not rushed.

We specialise exclusively in TDI technical diving courses,
delivering disciplined training for divers progressing into decompression,
extended range, trimix, and closed-circuit rebreather diving.

Our approach is simple: strong foundations, realistic dive planning,
and mentorship that continues beyond certification.

  • TDI-certified technical diving instructors with real-world experience
  • Small class sizes for focused, individual development
  • Training designed for demanding conditions
  • Clear progression pathways — not fast-track certifications
  • Ongoing mentorship beyond the course

Technical Diving Training with Purpose

Technical diving is not about chasing depth — it is about:
planning, control, and disciplined decision-making under pressure.

ESS-TEK TDI training focuses on decompression theory, advanced gas planning,
redundant equipment configuration, failure management, and team protocols —
the skills that define competent technical divers worldwide.

Why Train with TDI?

Technical Diving International (TDI) is one of the world’s
most respected technical diving agencies, trusted by divers operating
in challenging environments across the globe.

TDI’s modular system allows divers to progress methodically, build experience
at each stage, and develop skills that transfer across open-circuit and
closed-circuit technical diving.

Ready to Go Beyond Recreational Limits?

If you’re ready to begin technical diving training in the UK,
ESS-TEK provides the structure, experience, and mentorship to take you there.

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What Is Technical Diving?

TDI Technical Diving Courses (ESS‑TEK – Essex Scuba)

Course NameDepth LimitGas Mixes UsedEquipment ConfigurationCore Skills & Focus AreasWho It’s For
TDI Intro to TechNo formal depth increase beyond recreational limitsAir & NitroxTwinset, Sidemount, Stage exposureBuoyancy & trim mastery, propulsion techniques, team protocols, equipment configuration, foundational technical skillsDivers preparing for technical progression and decompression training
TDI Advanced NitroxUp to 40 mUp to 100% O₂Twinset or sidemount + deco cylindersUse of high‑oxygen mixes, accelerated decompression, gas analysis, oxygen exposure managementDivers seeking to extend bottom times and prepare for staged decompression
TDI Decompression ProceduresUp to 45 mNitrox, OxygenTwinset + deco stage(s)Staged decompression, ascent planning, gas switch discipline, emergency decompression managementDivers ready to begin formal decompression diving
TDI Trimix (Helitrox / Entry‑Level)Typically 45–55 mHelitrox (O₂ + N₂ + He)Twinset + stagesReduced narcosis, gas density awareness, helium‑based gas planningDivers progressing beyond nitrogen‑based decompression
TDI Advanced TrimixUp to 100 m (hypoxic trimix)Full Trimix (He‑based deep mixes)Twinset + multiple deco stagesHypoxic gas management, deep bailout planning, advanced emergency skillsExperienced technical divers progressing to extreme depth
TDI CCR Air Diluent Diver30 m, no‑decompressionAir diluentInspiration CCRLoop management, buoyancy, oxygen monitoring, checklists, emergency drillsDivers beginning their closed‑circuit pathway [bing.com]
TDI CCR Helitrox DiverExtended depth beyond air‑diluent limitsHelitrox diluent (He‑based)Inspiration CCRReduced narcosis, gas density optimisation, multi‑gas CCR decompression, performance‑focused helium useCertified CCR divers wanting clarity, efficiency & controlled decompression diving [bing.com]
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