We need to talk about the invisible deathtrap that is CO2 canisters

[Zafhset]

I don't think there is a need to change the way CO2 works at all.

CO2 cans fills the niche gap of a non-loud and silent way to sabotage the station via atmospherics - it is the closest you can get to poisoning the air without raising alarm bells the second a person sees something or experiences symptoms. if you make it anymore obvious people would just opt to release plasma and set the station on fire instead.

There are only about 4 cans of this thing on station in relatively secure locations, and even then if you use it to fill a room or hallway too large it won't work due to how little CO2 there is in a single can. In the times I've used CO2 it works about 50% of the time, it is hilariously easy how it gets foiled by any broken window/missing floor tile, or even by a door leading to a large hallway being bolted open.