This course provides training and experience required to competently utilise air for dives up to 55 msw that requires staged decompression, unitising Nitrox mixtures or oxygen during decompression. The objective of this course is to train divers in the proper techniques, equipment requirements, and hazards of deep air diving to a maximum of 55 msw utilising Nitrox mixtures or oxygen for staged decompression.

Qualifications of Graduates

Upon successful completion of this course, graduates may engage in decompression diving activities without direct supervision so long as:

1. The diving activities approximate those of training.
   
2. The areas of activities approximate those of training.
   
3. Environmental conditions approximate those of training.
   

Upon successful completion of this course, graduates are qualified to enrol in:

1. TDI Advanced Wreck Course.
   
2. TDI Entry Trimix Course.
   
3. TDI Advanced Trimix Course.
   

Student Pre-Requisites

The student must:

1. Be a minimum age of eighteen (18).
   
2. Be certified as a TDI Advanced Nitrox Diver and TDI Decompression Procedures Diver
   
3. Have a minimum of one hundred (100) logged dives, of which twenty (25) must be deeper than 30 msw, or the equivalent at the discretion of the instructor.
   

Required Subject Areas

1. History of Deep Air Diving.
   
2. Physics
   
   • Pressure Review.
     
   • Formulas for solving dive planning problems, MOD, best mix, etc.
     
3. Physiology
   
   • Hypoxia.
     
   • Oxygen toxicity
     
     • Whole body (OTUs).
       
     • Central Nervous System.
       
   • Nitrogen Narcosis.
     
   • Nitrogen Absorption and Elimination.
     
   • Carbon Dioxide Toxicity.
     
   • Carbon Monoxide.
     
   • Hyperthermia.
     
   • Hypothermia.
     
4. Decompression Options
   
   • Air.
     
   • Nitrox.
     
   • Oxygen.
     
5. Equipment Considerations
   
   • Twin cylinder or single cylinder option.
     
   • Stage cylinder options.
     
   • Regulator options.
     
   • Harness / BC options.
     
   • Computer / depth gauge / bottom timer options.
     
   • Ascent and navigation reels.
     
   • Lift Bags/surface marker buoys for drifting or free decompression.
     
   • Lights.
     
   • Redundant mask and knife.
     
   • Jon-line or Garvin clips.
     
6. Dive Tables
   
   • Introduction and review of different models (Buhlmann, DCIEM, U.S. Navy recommended).
     
   • Introduction to computer generated tables.
     
7. Dive planning
   
   • Operation Planning
     
     • Support.
       
     • Teams.
       
   • Team planning
     
     • Gas requirements.
       
     • Oxygen limitations.
       
     • Nitrogen limitations.
       
   • Emergency Planning
     
     • Omitted decompression.
       
     • Oxygen toxicity.
       
     • Decompression sickness.
       
     • General.
       
8. Procedures
   
   • Bottom, Travel and Decompression Gas.
     
     • Normal Operations.
       
     • Failure, loss or inadequate emergency procedures.
       
     • Analysis and logging.
       
   • Descent
     
     • Methods of entry, down lines or free descent.
       
     • Recognising narcosis.
       
     • Breathing.
       
     • Organization of equipment carried on diver.
       
   • Ascent
     
     • Variable rates.
       
     • Trim and compensation.
       
   • Support.
     
   • Navigation
     
     • From shore.
       
     • From descent Line.
       
     • From live-a-board vessel.
       

Required Skill Performance And Graduation Requirements

The following open water skills must be completed by the student during open water dives: The maximum depth for this course is 55 msw.

1. Properly analyze all gas mixtures to be used
   
2. Demonstrate adequate pre-dive planning
   
   • Limits base on personal and team gas consumption
     
   • Limits based on oxygen exposures at planned depths for actual mixes
     
   • Limits based on nitrogen absorption at planned depths for actual mixes
     
3. Properly execute the planned dive within all pre-determined limits
   
4. Demonstrate the proper procedures for switching and isolating a malfunctioning regulator. This skill is to be performed at a depth no deeper than 40 msw
   
5. Demonstrate the proper navigational techniques for the specific dive
   
6. On two (2) dives, demonstrate an ascent with ascent reel and lift bag. Perform staged decompression
   
7. On one (1) of the dives, tow a simulated unconscious diver, while at depth, thirty (30) ft to ascent line and simulate an emergency rescue ascent technique
   

In order to complete this course, students must:

1. Satisfactorily complete the TDI Extended Range Course written examination.
   
2. Complete all open water requirements safely and efficiently.
   
3. Demonstrate mature and sound judgment concerning dive planning and execution
   

Equipment you will need to buy prior to course;

• Depth gauge and automatic bottom timer or dive computer. – 2 devices required
  
• Regulator(s) – 2 bottom and 2 deco all in oxygen service and DIN. A long hose (2m) is required on one bottom regulator
  
• Submersible pressure gauges are required on bottom cylinder and each stage cylinder.
  
• Wing-style BCD bladder with at least 20 Kg lift for bolted twinset with harness and backplate
  
• Line cutting device
  
• Ascent Reel with Lift Bag /Surface Marker Buoy.
  Exposure Suit adequate for the open water environment.
  
• Underwater Slate.
  
• 2 meters black surgical tubing
  

You can hire all the above from us - see price list for costs. If Equipment is needed then a 10% discount will be applied over Price List. Please let us know in advance.

The Price includes all gas but there is an additional fee for certification and manual - see price list. Also if more than one TDI course is booked for consecutive attendance and paid for in advance a 10% discount will apply to the total course costs (excluding certification fee).

Please also remember to bring your GP signed medical with you (form available on website).

Please also check out our terms and conditions, packages available, price list, and the medical statement from the booking pack or from our website, and feel free to ask any questions you may have.