Why do you need training for normoxic trimix?

[Merlino]

In answer to the OP's question of why is there a need for normoxic trimix traiing..

The answer is multi-factored, but the most important reason is to give a baby stepping stone instead of a giant leap. As others have said, the math is basically the same as you learned in deco, but what is different are the physical in-water skills. For instance, in Normoxic Trimix you're now working with multiple deco bottles and the gas is going quicker at 200' than it does at 130-150'. This means learning how to manage the extra gear and learning how to solve problems quicker/more efficiently because of the diminished problem solving time of being at 7ATA versus 5ATA.

Thanks for your insightful answer. I learned from your answer (and that of others) that it’s not so much the helium itself but other considerations that come naturally with starting to dive trimix.

I liked the suggestion below to tack on a triox module to C1 that I’ll hopefully be doing later this year. Looking forward to it!

 

[Superlyte27]

Isn't the progression also about handling more stages? ART: 1 stage, normoxic: 2 stages and avoid switching error, hypoxic: leash, ...

You can go directly from AN&DP to Normoxic.

Lots of people are diving 5+ bottles with just AN&DP