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Question How long it takes for the average, untrained person to black out when doing static apnea?

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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New Member
Nov 23, 2023
For safety purposes, on paper, how long would it take for the average, untrained person to black out when doing static apnea? I know it is technically impossible because they’ll probably come up for air way earlier, assuming they’re untrained, which’s why I’m asking it just on paper. How height, weight, gender and age affect it? Can you raise this time so you have more time in a dangerous situation like being trapped unexpectedly underwater?
Thank you :)
Blackout :—> caused by …the rapid drop in the partial pressure of oxygen in the lungs .)
more details : https://en.wikipedia.org/wiki/Freediving_blackout#See_also
PAO2 and during normal conditions (at sea level) it correspond to 75 to 100 mmHg. From : https://www.ncbi.nlm.nih.gov/pmc/ar...The rate of oxygen diffusion,to 100 mmHg [24].

The blackout threshold is 25 to 30 mm Hg.

Look at the graphic at 6:12 from the video below
Can occurs more than 30 s after surfacing

Don't hyperventilate.
Practice CO2 tables to improve your breath resistance always with a buddy able to rescue you
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