TDI Extended Range

Course Overview

TDI Extended Range trains experienced technical divers to use compressed air as a breathing gas for deeper staged decompression dives where helium may not be available. TDI identifies a maximum depth of 55 metres/180 feet and describes the course as covering the proper techniques, equipment requirements, and hazards of deep air diving. Students also work with nitrox mixtures or oxygen for decompression, so the course demands careful gas planning and disciplined execution.

This course is for certified TDI Advanced Nitrox and Decompression Procedures divers, or equivalents, who are ready for the next technical step. TDI lists minimum age 18 and proof of at least 100 logged dives, with 25 deeper than 30 metres/100 feet, before training begins. Students should already be comfortable with stage bottles, decompression planning, team protocols, and precise buoyancy.

Training covers deep air physiology, decompression options, MOD and best-mix planning, equipment considerations, lift bag ascents, contingency schedules, gas matching, regulator failures, and demanding rescue-style scenarios. In High Springs, Florida, it is a serious bridge toward trimix, advanced wreck, or deeper expedition-style dives. Successful students should leave with a more realistic respect for deep air limits and a stronger technical planning process.