Comments by "possumverde" (@possumverde) on "The Infographics Show" channel.

The only humane for of execution is nitrogen asphyxiation. No one uses it... It's simple, painless, safe, and cheap. The suffocation response by the body isn't triggered as air pressure in the lungs barely changes and the victim doesn't end up inhaling their exhaled breath so no carbon monoxide/dioxide poisoning occurs either. They feel fine, then feel drunk for a few seconds, then pass out and eventually die while unconscious. Never knowing what hit them. All it requires is a room where nitrogen gas can be pumped in and the normal atmosphere out. Since oxygen and carbon dioxide/monoxide are heavier, they will sink to ground level and be easily pumped out. Nitrogen is heavy enough to prevent much of a loss in air pressure so the person continues to breath normally not realizing that they're not getting oxygen. They become euphoric temporarily and then they're out. Unlike other methods, no nasty chemicals are involved so the chamber can be vented into the open air safely.
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