Re: Dry ice in the ice chamber?
it wouldn't get into his lungs if he had it in the chamber. Dry ice vapor is denser than air so it sinks. It would give a very cool effect but I Would be more worried about the metal itself and the integrity of the welds. Putting it on your base is stupid but the may work. Km hookahs have a very tall bowl platform as well adding to the safety.
Oh and I would not try to handle your stem with bare hands. I think it is safe for you and you should try it. It will look damn cool.