[eecc]

Well, CO2 asphyxiation is so far the most humane approach to butchering.

I remember a YouTube of a journalist looking for the most humane technique to administer capital punishment and it turned out that during co2 asphyxia the victim goes light-headed, even laughingly before passing out and away without even realizing. When told about this, Death Sentence advocates were disappointed that the victims wouldn't suffer while the sentence was carried out. (surprising eh!)

[denton-scratch]

CO2 asphyxiation is not kind. The effect of elevated CO2 blood levels is to make you panic that you are suffocating; you struggle for breath. Nitrogen gas is much kinder; you don't know that you are suffocating, you just pass out. (So be extra-vigilant around tanks of N2).

[mplanchard]

Nitrogen asphyxiation is even better, and atmospheric nitrogen is extremely abundant and super cheap.

[marliechiller]

not sure what your definition of humane is but mine certainly isnt this: https://www.youtube.com/watch?v=-7hAELEBjX4