Hypoxia and hyperventilatiion
Surfing https://news.ycombinator.com/item?id=43724523
Oxygen mask https://news.ycombinator.com/item?id=43723317 https://news.ycombinator.com/item?id=43723706
As a pilot, it was eye opening to see first-hand what happens to me when experiencing hypoxia. The trainers were talking to me, and I was replying, but was unable to tell them what 17 minus 4.5 was.