HeliAir 5x MaxDepth "Rule of Thumb"

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beldridg

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I almost always dive HeliAir for my Diluent and I typically have mixes ready with 30ish, 40ish, 50ish, and 60ish percent Helium in my 4 Dil bottles since I'm never quite sure what I'm going to dive.

The other day it dawned on me that there is a simple "rule of thumb" for calculating max depth for a given Helium percentage in a HeliAir mix (given that you never really have to worry about Dil ppO2 MOD with HeliAir).

Maybe I'm just slow to realize this, but if you multiple the percentage of Helium by 5, you have a good approximation of max depth to maintain an END of 100' and an EADD (equivalent air density depth) of 100.

For example, the ever popular 10/50: At 5 x 50%, that would be 250'. At 250' with 10/50, the END is 93' and the EADD is 112' (at least according to CCR Mixer).

Sorry if this is just a "yeah, of course you moron" and that I'm just slow to realize it. But hopefully it will help a few others. :)

Regards,

- brett
 
Anything that makes easier math is always welcome! Thanks Brett It helped me. Now I just need to get that Helitrox class out the way next year with Paragon to utilize it.
 
https://www.shearwater.com/products/teric/

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