For those wondering (if any), those 5gm of Oxygen is about 7L in volume. Taking 20% oxygen concentration for normal breathing, that's like 35L of breathable air. Taking 0.5L tidal volume (inhale volume/breath) that's like 17 inhales? Average breathing rate is somewhere between 12-20/minute. Let's say 17, so that's like 1 minute worth of proper breathing? 🤔 But then the actual reduction in O2 concentration in exhaled air is around 5%, so like 20x the duration = 20 minutes of breathing? So... okay my brain hurts now. No idea why I wrote this but I hope you have a nice day