As your motivation to explore progresses you will find that you may want to go deeper to dive that wreck that is part of history or that cave system that you have read so much about. One of the major limiting factors of going deeper is narcosis; TDI’s Trimix Diver course shows how to minimize the effects of narcosis by adding helium to offset the nitrogen in your breathing gas. While taking the Trimix Diver course your TDI Instructor will teach you how to plan and execute dives utilizing as little as 18 percent oxygen and diving to maximum depth of 60 m/200 feet with a blend of helium appropriate for the planned depth. The course covers topics and skills like
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