Cavern Discovery

Are you a serious adventure seeker wishing to explore overhead environments? Sign up for the TDI Cavern Diver course! This course is designed to develop the minimum skills and knowledge for cavern and overhead environment diving within the limits of light penetration, and outline specific hazards associated with cave diving. The cavern diver course in not intended to provide instruction for cave diving environments. The objective of this course is to train divers in the proper planning, procedures, techniques and hazards of cavern diving.

What you can expect to learn

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

Some of the required skills you will have to demonstrate include:

• Properly deploy a guideline
• Properly follow a guideline with eyes open and closed (simulating loss of visibility)
• Air share with a buddy with eyes open, following a guideline
• Air share with a buddy with lights off and eyes closed, using touch contact while following the guideline
• Remove and replace mask while in contact with the guideline
• Demonstrate conservation, awareness, and back referencing techniques
• Demonstrate light/hand signals and touch contact
• Demonstrate anti-silting techniques
• Simulate a primary light failure and use back up light to exit
• Demonstrate buoyancy control, proper trim, and propulsion techniques
• Equipment check and matching
• Demonstrate adequate predive planning

Course Equipment Requirements

Suggested reading materials: 

• TDI Diving In Overhead Environments manual

The following equipment is required for each student:

• Primary cylinder, volume appropriate for planned dive and student gas consumption
• Regulator with pressure gauge and alternate air source; although not required, it is suggested one regulator be mounted on a hose approximately 2 metres / 7 feet in length
• Buoyancy compensator device (BCD) with power inflator
• Exposure suit adequate for cavern environment
• Mask and fins, NO snorkel
• Line cutting device
• Safety reel with a minimum of 37 metres / 125 feet of guideline
• One primary cavern-diving reel with length appropriate for intended dive (instructor may provide)
• Two battery powered lights, with burn time suitable for the planned dive time
• Computer or watch (bottom timer) and depth gauge
• Slate or wet notes and pencil (recommended)
• Submersible dive tables or backup dive computer (recommended)
• Weight system

Course Prerequisites

• Minimum age 15 with parental consent
• Provide proof of certification as an SDI Open Water Scuba Diver or equivalent
• Provide proof of a minimum of 25 dives