• The certified TDI Cavern Diver/TDI CCR Cavern Diver or equivalent who has interest in moving forward with overhead environment diving and expanding their diving techniques, capabilities, and more!

(these requirements must be met prior to commencement of training):

• Minimum age 18, 15 with parental consent
• Provide proof of an SDI Open Water Scuba Diver or equivalent
• Proof of 25 logged dives

Rebreather Divers

• Minimum age 18
• Minimum certification requirement: TDI CCR Air Diluent Diver, or equivalent
• Provide proof of a minimum of 25 logged dives and 25 hours on the rebreather unit used in training

The TDI Cavern Diver course takes an in-depth look at all of the following and more:

• Policy for cavern diving
• Gas management procedures and management to include dissimilar volumes
• Psychological considerations of cavern diving
• Equipment considerations including:
  • Cylinder options
  • Regulator options
  • Buoyancy compensator/harness options
  • Proper weighting
  • Reel options
  • Equipment configurations
• Communication (light and hand signals)
• Swimming techniques
  • Body posture/trim
  • Buoyancy control
  • Line following
  • Propulsion (finning) techniques
• Physiology
  • Breathing techniques
  • Stress management
• Cavern environment
• Cavern conservation
• Problem solving
  • Emergency procedures
  • Equipment failure
  • Silting conditions
• Accident analysis
• Cavern diving etiquette
• Review of dive tables and decompression theory

The TDI Rebreather Cavern Diver Course takes an in-depth look at all of the following and more:

• Policies for rebreather cavern diving
• Psychological considerations
• Equipment considerations
  • Bailout cylinder options
  • Rebreather configuration options
  • Scrubber options
  • Buoyancy compensator device (BCD) / harness options
  • Reel options
  • Proper weighting
  • Equipment configurations
• Communication
  • Hand signals
  • Light signals
  • Touch contact signals
• Swimming techniques
  • Body posture / trim
  • Buoyancy control and rebreather weighting
  • Line following techniques
  • Propulsion techniques
• Physiology
  • Breathing techniques
  • Stress management
• Cave environment
  • Geology
  • Local access requirements
  • Land owner relations
• Conservation
• Problem solving
  • Equipment failure
  • Silting conditions
• Accident analysis
• Review of dive tables and decompression theory
• Cavern diving with Open Circuit (OC) divers
  • Bailout configuration requirements
  • Out of gas emergencies
• Cavern diving etiquette

Upon successful completion of this course, graduates may engage in cavern diving activities without direct supervision so long as the following limits are adhered to:

• The diving activities approximate those of training
• Planned dives do not exceed diver’s current certification level
• Penetration is limited to the “rule of thirds,” OR 1/6th if using doubles to a maximum depth of 40 metres/130 feet
• Penetration is limited to 61 linear metres/200 linear feet from the surface
• Proper cavern diving equipment must be used
• Maintain a continuous guideline
• No restrictions or areas that are too small for 2 divers to swim side by side
• Safety stops as appropriate or necessary

Upon successful completion of this course, graduates may engage in rebreather cavern diving activities without direct supervision provided the graduates adhere to the following requirements:

• Daylight zone, i.e. within natural light of the cavern entrance
• Diver carries adequate bailout to safely exit from the furthest point of penetration using a minimum SACrate of 30 litres per minute/1 cubic foot per minute OR the student’s calculated elevated SAC rate to account for a CO2 event, whichever is greater
• 60 linear metres / 200 linear feet from the surface
• 30 metres / 100 feet maximum depth
• No decompression diving
• No restrictions; no areas too small for 2 divers to pass side-by-side
• Safety stops as appropriate or necessary
• Maintain a continuous guideline
• Proper cavern diving equipment is used in conjunction with a TDI approved rebreather
• No removal of life support equipment shall be permitted within the overhead environment
• Visibility must be adequate to identify the exit from inside the cavern

Upon successful completion of this course, graduates are qualified to progress on to the next level of overhead environment training: the TDI Rebreather Intro to Cave Diver course!

• Perform all land drills and cavern dive requirements efficiently
• Demonstrate mature, sound judgment concerning dive planning and execution
• Maintain an appropriate level of awareness and respect for the environment
• Log all training dives