Now, there are no official rules for poison gas and not choke gas, smoke, and such. Has anyone made some house rules for this part of the universe?

numb3rc said:

There are rules for creating poisons in the GM's Kit , which can be administered in any way you care to imagine. The rules define three things: how quickly the poison takes effect (instantly, in a few hours, or in a few days), how difficult the poison is to resist (modifying the toughness test to resist), and what it does when it takes effect (it could be extra damage like the Toxic trait, or it could cause unconsciousness, paralysis (through strength damage), or toughness damage). There's an expansion of those rules in The Radical's Handbook, adding a few more options.