Course Overview
TDI Rebreather Cavern is the first course in TDI's rebreather overhead-environment progression. The official TDI page describes it as training the necessary skills to conduct cavern dives using a TDI-approved rebreather. Even though the course remains in the daylight zone, the diver is still entering an overhead environment, so the focus is on careful configuration, bailout planning, line procedures, conservation, trim, and disciplined control throughout the dive.
This course is for qualified rebreather divers who want to begin cavern training while using their unit rather than open circuit. The course is not full cave training and should be treated as a controlled introduction to rebreather overhead procedures. Students should already be comfortable monitoring PO2, managing loop volume and buoyancy, and carrying sufficient bailout for the environment and planned penetration.
Training covers equipment configuration and preparation, body posture, trim, propulsion, cavern conservation, proper guideline procedures, bailout considerations, light and communication skills, touch contact, and procedures drawn from the TDI Overhead Environment manual. In High Springs, Florida, it is a practical first step for CCR divers entering the spring cavern environment. Successful students should leave with better rebreather-specific overhead habits and readiness for Rebreather Intro to Cave.
