TDI Adv Nitrox & Deco Procedures

With coffee in hand and enjoying the gentle sea breeze,

Day 2: Rigorous Precision & First Technical Dives

With the pool session behind you, Day 2 transitions your skills into the open water. Today is all about precision, accountability, and transferring your safety drills into the ocean environment.

Morning: Advanced Theory & Technical Prep

We kick off the morning by continuing your instructor-led academics. Your instructor will also work with you to make any necessary equipment and harness adjustments based on how your rig felt in the pool on Day 1.

Before the lunch break, you will dive into essential technical pre-dive procedures:

• Gas Analysis: Personally analyzing your breathing and decompression gases.

• Cylinder Labeling: Correctly marking your tanks with gas contents, oxygen percentages, and Maximum Operating Depths (MOD).

• Dive Planning Validation: Confirming run times and gas matching schedules based on your actual mixes.

Afternoon: Open Water Dives 1 & 2

After lunch, we board the Big Blue Tech boat for your first two technical training dives. The absolute focus of this afternoon is mastering the skills practiced in the pool, with zero compromise on your positioning.

During these dives, you will focus on:

• Flawless Buoyancy & Trim: Maintaining a rock-solid horizontal profile and staying perfectly stable in a fixed water column while executing skills—a non-negotiable requirement for safe decompression diving.

• In-Water Drill Execution: Performing real-world valve shutdowns, emergency gas sharing, and simulated backup mask deployments in open water.

• Stage Cylinder Management: Managing your decompression cylinder smoothly during entries, exits, and while moving through the water column.

Evening: Analysis & Debrief

Back on land, we head to the restaurant to review the day’s training. With a cold drink in hand, your instructor will deliver a comprehensive debrief of the afternoon’s activities, focusing on your trim, stability, and areas to fine-tune for your final graduation dives.

Day 3: Simulated Decompression & Technical Mastery

On the final day of your course, the training wheels come off. Day 3 focuses on team dynamics, meticulous planning, and executing simulated technical dives from start to finish.

Morning: Land Drills & Precision Decompression Planning

We start the morning by stepping away from the classroom and focusing on critical pre-dive team protocols. Your instructor will deep-dive into the logistics of your upcoming dives, allowing you to formulate and plan an actual decompression profile.

Before heading to the boat, we will conduct intensive land-based drills to ensure your mechanics are flawless:

• Team-Led Gas Switching: Mastering the exact verbal and physical communication steps required before breathing from a decompression cylinder.

• Coordinated Team SMB Deployment: Practicing how a technical team launches a surface marker buoy efficiently while maintaining depth.

• Pre-Dive Buddy Checks: Executing rigorous technical checks (GUE-EDGE / S-Drills) to ensure every team member’s equipment is fully functional and accessible.

Afternoon: Technical Dives 3 & 4 (The Graduation Dives)

After lunch, we board the boat for your final two training sessions. These are simulated decompression dives—meaning that while you will remain safely within your actual recreational limits, you must manage the dive as if a real physical ceiling exists.

To successfully graduate, you will demonstrate true mastery of the following under your instructor’s evaluation:

• Real-Time Problem Solving: Calmly and efficiently responding to simulated equipment and gas failures at depth.

• Disciplined Gas Transitions: Executing flawless, team-verified switches to your decompression gas.

• The Decompression Ascent: Maintaining absolute depth control and horizontal trim while executing your planned decompression stops and ascent schedule as a unified team.

Evening: Certification & Sunset Celebrations

Back on land, we return to the beachfront bar to conduct your final course debrief. Once your instructor signs off on your technical logbook, you can officially celebrate your successful completion of the TDI Advanced Nitrox & Decompression Procedures course. Grab a cold drink, and toast to breaking past the NDLs!

Day 4: The Decompression Dives & Graduation

The wait is finally over. Today is the culmination of all your hard work, where you step past recreational limits and execute actual, planned decompression dives.

Morning: Final Validation & Technical Prep

We begin the morning by ensuring all your online academics are fully wrapped up. Your instructor will review your coursework, analyzing and discussing any incorrect answers to ensure your theoretical knowledge is absolute.

Before we head to the boat, the team swings into motion for final technical preparations:

• The Final Plan: Utilizing decompression software to finalize your exact runtime schedules and ascent profiles.

• Gas Analysis & Accountability: Personally analyzing your breathing and decompression gases to confirm your safety margins.

• Cylinder Labeling: Marking your tanks with precise oxygen percentages and Maximum Operating Depths (MOD).

• Final Land Drills: Running through gas-switching mechanics and team communication one last time on land.

Afternoon: Open Water Dives 5 & 6 (The True Decompression Experience)

After lunch, we board the boat for the moment you’ve been training for. You will execute two actual decompression training dives, showcasing complete mastery of the skills, trim, and safety protocols you’ve perfected over the course.

• Executing the Plan: You will manage your ascent and hold your decompression stops with absolute precision in the water column.

• An Unforgettable Milestone: Experiencing the true discipline and focus of technical diving, this afternoon will be an experience you will never forget.

Evening: Debrief & Sunset Celebrations

Back on land, your instructor will conduct your final course debrief and sign off on your technical certification. You can reflect on your massive achievement over the last few days, grab a well-deserved celebratory drink at the bar, and watch the Koh Tao sunset with your new technical dive buddies.

This is a flexible day that can be utilised as required e.g. an additional training day may be required after day 2 or 3 prior to your decompression dives. If however the course has been successfully completed in 4 days. 2 fun deco dives can be taken with one of our Technical instructors.