With co2 it takes about a min. + to die. The compressed air takes LESS than 30 sec. My last feeder took 10 sec. That seems a lot shorter and easier than co2. I did some research about the gas that is used in the compressed air. One of the gases used is Difluoroethane. The inhalation of this gas is famous for people who "huff". But in huge doses with out o2 can cause cardiac arrest. The other gas used is trifluoroethane which is used for the accelerant. As far as harming the snakes: I researched this topic what I found is quite good... The amount of gas in the lungs is extremely small. When gas is ingested it doesn't get absorbed in the body. Think of it like air when you swallow it. It gets released by either as a burp or breaking wind. The gas is 100% harmless to the snakes.