Relative to the additional alleged execution facilities of Chelmno (gas vans), Belzec, Sobibor, Treblinka and any others, it should be noted that carbon monoxide gas was allegedly used.
As discussed above, carbon monoxide gas is not an execution gas and the author believes that before the gas could take effect, all would have suffocated. Therefore, it is the author's best engineering opinion that no one died of CO execution.