Why would anyone think that breathing nitrogen would result in unconsciousness in seconds?
Most of the air we breathe is nitrogen. It is the absence of oxygen that eventually causes death, but that will take some time.
Most of the air we breathe is nitrogen. It is the absence of oxygen that eventually causes death, but that will take some time.
In it, a man investigates various means of execution, and concludes that nitrogen asphyxiation is the most 'humane' because the victim just passes out and then perishes. The presenter isn't necessarily wrong, but the caveats include a) the victim must breathe pure nitrogen, any oxygen present will prolong the experience; and b) if the victim is aware they are being executed, it is unlikely to be peaceful regardless.
Edit to add: Also, the physical discomfort from holding one's breath comes from increased concentration of CO2 in the blood, not the absence of oxygen. So as long as one can expel CO2 as usual, the lack of oxygen does not cause physical distress.
Is there some physiological difference between holding your breath and constantly breathing?