Coke's Planet-Friendly Vending Machines - Forbes.com
""He notes that carbon dioxide is nonflammable, nontoxic, ""
Well it can still kill you enough of it in an enclosed space will thin out oxygen and kill you.
If refrigerators start coming out with this as they had in the 1930,s you will find sooner or latter some one will brake the seals coils evaporators etc and release this co2 and if no windows open death can result.
Still far better then using ammonia as many had back then.