Course Overview
TDI Mixed Gas CCR is an intermediate closed-circuit rebreather course for divers ready to extend beyond air diluent decompression or helitrox CCR limits. The official TDI page describes training to a maximum depth of 60 metres/200 feet using helium as a diluent and oxygen levels as low as 16 percent. The course emphasizes the planning precision required when CCR technology, mixed gas, decompression, and bailout logistics all overlap.
This course is for certified TDI Air Diluent Decompression or Helitrox Diluent Decompression CCR divers, or equivalents, who want to extend their depth limitations. TDI lists minimum age 18, completion of the appropriate prior CCR decompression course, and a verified log of at least 50 rebreather hours over at least 50 dives on the specific rebreather, with limited credit possible for hours on another recognized CCR unit.
Training covers gas physiology, hypoxia, helium and nitrogen absorption, HPNS, gas mixing, oxygen tracking, custom decompression tables, constant PPO2 planning, bailout gas requirements, fuel cells, loop configuration, team procedures, gas shutdowns, SCR drill, DSMB deployment, staged decompression, and recovery from system failures. In High Springs, Florida, it is a major step toward deeper CCR diving. Successful students should leave with stronger mixed-gas planning and unit-specific emergency control.
