CO is toxic. CO2 is inert. CO2 does not kill, it simply displaces O2, which is vital for life. Simply ventilating the gas chamber restores it to a safe condition. Much safer.
They would cough to death in great distress.
CO2 is not physiologically inert. However, killing inmates with CO2 might help reverse global warming.
“CO2 is inert. CO2 does not kill, it simply displaces O2”
No, that’s not correct. Excess CO2 triggers the need to take a breath. In other words, you know it when the CO2 level goes too high.
With nitrogen you don’t have that reaction.
Don’t know that an entire chamber would be required to be filled with nitrogen the way the traditional cyanide gas chamber was. Just strap the POS to an immovable chair, seal a mask over his face, and turn on the nitrogen. Permanent nitey nite.
Go into a space with a bulk CO2 fire suppression system and trip it. Experience convulsions, arrhythmia, tachycardia, heart failure, massive stroke, coma or all together.