Course Overview
TDI Semi Closed Rebreather is an entry-level course for recreational divers who want to use a TDI-approved semi-closed circuit rebreather. The official TDI page explains that the course teaches the benefits, hazards, and proper procedures for SCR diving. Students learn how semi-closed systems differ from open circuit and closed circuit rebreathers, how gas use and oxygen exposure are managed, and why unit-specific setup and monitoring are central to safe diving.
This course is for nitrox divers interested in extending bottom time with a semi-closed rebreather. TDI lists minimum age 18, or 15 with parental consent, and TDI Nitrox Diver or equivalent as prerequisites, with nitrox sometimes combined at the instructor's discretion. It is a good fit for divers who want quieter, more efficient dives without moving directly into CCR technical training.
Training covers rebreather history, system mechanics, assembly and disassembly, scrubber handling, maintenance, nitrox review, PO2 monitoring, gas physiology, dive planning, problem solving, bailout, and open-water skills. In High Springs, Florida, it is a useful way to explore rebreather procedures in a controlled progression. Successful students may conduct no-decompression SCR dives to 40 metres/130 feet within training-like conditions and nitrox limits.
