From what I’ve read, it’s due to the fact that they’re strapping a mask to their faces. The exhaled gasses have nowhere to go, it mixes with the inert gas, and doesn’t cause a loss of consciousness as quickly as intended.

Even if they managed the exhaled CO2 correctly (wtf they didn’t?!), that requires the CO2 to actually be exhaled. But someone who doesn’t want to die that’s being killed by asphyxiation is naturally going to hold their breath, which means the CO2 stays in them, ruining the whole point.

Inert gas seems like a great choice for a self elected procedure, but could probably never go well for execution, because the theory of why it works (asphyxiation without the CO2 buildup that causes pain) requires cooperation.

Oh yeah that would be an issue. When I first heard about it I was picturing a similar setup to the nitrogen chambers used for like hypoxia practice for pilots? It’s a whole room that fills with nitrogen, you don’t even know that anything is wrong, you just start getting confused and then pass out if it goes on long enough

5% is quite high. And maybe I’m just an oddball but I think I’d take some solace from being guillotine’d since it’s got such interesting cultural context