As someone moving to CCR this was incredible. Even at 9 years old

Awesomely Enlightening, thanks for posting. I think the engineer's question (and he asked to verify) was correct (what he was seeking). The End Tidal concentration was shown to be the highest concentration in the exhalation evolution, so electronically, the engineer only needs to capture the signature's PEAK VALUE (of CO2 concentration)...and that would be End Tidal CO2 concentration. Use a Peak Detector Circuit for End Tidal Examination. Aloha!

Great share - good to see you diagnosed the cause 👏🏻

Fantastic, thank you for posting this!

I am so glad I found this!!!!

Something that doesn’t make sense is the explanation of ( and his physician students struggle with) is the notion of flow restriction at depth. The Bernoulli equation is 1/2 Area * density of gas * velocity squared. So sure density of gas increases with depth but to achieve the same mass flow rate the velocity reduces exponentially. The explanation of airway restriction as a result of increased exhalation effort (velocity) would have to weezing at the beginning of an exhale not the tail end of it.

thank you, that is a lot of valuable information!

I don’t even dive yet. Going to do my open water soon but this was very interesting

This guy is really an amazing presenter

One comment @ 20:40 - yes, the work of breathing does increase with depth, but as the gas is also denser, you’re also getting more gas into your lungs with each breath

Does the AP evp rebreather now have end tidal co2 monitoring?