Insecticide, Pesticide, Injecting Fire Into Room

[ToXeye]

I have an idea for taking care of insect infestations: Researching some way to make weapons that just kill a whole room.

Insecticide : A gas weapon

Pesticide: A gas weapon

Flame Thrower: A "Gas" Weapon

This would make the rooms affected in some way, so it would not be a 100% "free" solution. Making clothes tainted, for example.

Anyway, a "Fire Cloud" would be nice, and injecting gases and such into rooms through doors/vents would be nice