Rebreather Cave Class

The UTD Rebreather Cave Diver course is designed for Certified Cave Divers who are also certified on a rebreather (PSCR or mCCR) in the open water, training them to combine their skills to become certified and proficient in rebreather cave diving. This course seeks to both refine and develop divers who want to use their rebreather while conducting a cave dive to their current certification level. To succeed in this course, students must be practiced in the fundamental aspects of cave diving and comfortable in the use of rebreather diving.

Prerequisites

• Must meet UTD General Course Prerequisites as outlined in Section 1.6
• Minimum age of 21
• UTD mCCR 1 or PSCR 1 and UTD Cave Diver or equivalent. Divers who were not previously trained by UTD must first secure the approval of the UTD instructor before entering this class, and must be prepared to engage in supplemental training to remedy any training deficiencies. Additional time and fees are at the discretion of the instructor.
• Must have proof of at least 200 logged non-training dives, with at least sixty (60) non-training dives in a rebreather (non overhead) and at least twenty (25) non-training open-circuit cave dives
• Standard gases are used. Nitrox and/or Helium certification required if breathing any gas with higher O2 content than 22% and/or using a helium based mix.

Course Limits

• General Training Limits as outlined in Section 1.4.
• Student to Instructor ratio is not to exceed 3:1 during any overhead diving activity.
• Gas consumption: maximum rebreather use of 1/3 of gas supply,and enough reserve to exit while breathing Open Circuit bailout.
• No dives are to exceed the depth or penetration distance of a current certification level.
• Minimum 20 feet/6 meters of visibility to enter a cave.
• Minimum 130 cu.ft./3680 liters of gas to enter a cave.
• Minimum one O2 deco gas.
• No scooter diving.
• No goal-oriented dives.

Course Content and Duration

• The Rebreather Cave Diver course builds upon previously learned skills, focusing on extending cave and rebreather diving techniques. These skills include: a focus on environmental awareness, advanced gas management, problem resolution, stress management, self evaluation, advanced navigation, basic survey techniques, extended exposure strategy, and cave decompression management while using a rebreather and a single gas deco (oxygen).  This course is heavily experience-based, and includes many practical, task-oriented skills that must be mastered before a student is competent to safely dive at this level.
• The UTD Rebreather Cave Diver course is normally conducted over a 5-day period, and cumulatively involves a minimum of 40 hours of instruction (lecture and in-water) designed to instill divers with an appreciation for the dangers, challenges of rebreather in a cave environment.

Course requirements include a minimum of twelve (12) rebreather cave dives.

Texts

• Online Classroom Materials – UTD Rebreather Cave Diver.
• Gas Planning Worksheet.
• Technical Diver and Essentials of Rebreather Diver DVDs are recommended.

Academic Topics

• Reel and guideline use.
• Dive team order and protocols.
• Touch contact.
• Advanced navigation skills.
• Rebreather use in a cave.
• Gas management techniques, including for mixed teams.

Land Drills & Topics

• Reel and guideline use in standard operating procedures.
• Team order and protocols.
• Rebreather, reel and guideline use in emergency procedures, including touch contact and air-sharing techniques, including zero visibility.
• Advanced navigation skills.
• Visual referencing skills.
• Deco bottle configuration and procedures.
• Rebreather techniques.

Required Dive Skills & Drills

• All skills and drills as outlined in the General Diving Skills, Section 1.5.
• Pre-dive planning to include:
• Assess and review diving team limitations,
• Dive plan review,
• Equipment review,
• Equipment familiarization,
• Map use.
• Procedures for gas failures; including valve manipulation, air-sharing, and regulator switching (as appropriate).
• Gas-sharing scenarios to include:
• Breath hold management,
• Out of gas diver,
• Gas-sharing of at least 300 feet/90 meters,
• Comfortably swim at least 200 feet/60 meters without a mask while gas-sharing.
• Demonstrate adequate mask switching.
• Use of various propulsion techniques according to conditions.
• Use of touch contact for limited and simulated zero visibility situations.
• Use of line following techniques for limited/no visibility situations.
• Demonstrate the effective deployment of a reserve light in less than 30 seconds.
• Demonstrate excellent buoyancy control skills while maintaining PPO2’s.
• Demonstrate effective valve-management by switching regulators, shutting down a valve in less than 10 seconds and returning the valve to the open position again in less than 10 seconds.
• Demonstrate proficiency with guideline management in the following situation:
• Simulated zero visibility line following, incorporating touch-contact skills,
• Efficient deployment and removal of the guideline.
• Problem resolution, including line entanglement, navigation in restrictive areas, and multiple line management.
• Demonstrate advanced use of Rebreather in cave environment including critical failures.
• Demonstrate a calm demeanor while sharing air in a cave exit for at least 600 feet/200 meters.
• Demonstrate a calm demeanor while sharing air through a restriction, minimizing ceiling impact.
• Demonstrate a calm demeanor while sharing air in simulated zero visibility for at least 200 feet/60 meters.
• Rescue and emergency procedures.
• Perform the following Rebreather test:
  • O2 drop - Time calculation,
  • Volume drop - Time Calculation,
  • PPO2 cycle - Diluent addition only,
  • pSCR emergency exit mode.
•  Demonstrate proficiency with rebreather use and failures in cave environments.
  •   Unit flooding recovery,
  •   Hyperoxic mix problem solving,
  •   Hypoxic mix problem solving,
•   Demonstrate ability for Cave RB bailout exit with RB O2 bottle failure (mCCR),
•   Demonstrate ability for Cave RB bailout exit with main bottom gas supply failure,
•   Demonstrate ability for Cave OC bailout exit with catastrophic Rebreather failure,
•   Demonstrate mix team (RB and OC) dive planning.

Equipment Requirements

• All equipment noted in paragraph 3.0.
• Rebreather in UTD MX mCCR or PSCR configuration.
• Rebreather backgas/diluent cylinders should be large enough volume to facilitate using diluent from the backgas for the penetration and reserving enough volume to exit the cave swimming on open circuit backgas. Suggested minimum sizes are AL80s/85s/11L/12Ls or 120 cu.ft./18L..
• Three spools / reels, each with a minimum of 100’/30m of line per diver. One spool line must be knotted each 30’/10m.
• One primary reel per team, with a minimum of 200 feet/60 meters of line. Line must be knotted each 10’/3m.
• At least six line markers, of which at least 3 should be directional (line arrows) and 3 non-directional.
• 1 Oxygen 6m bottle, (AL40, 7L).