> Can anyone from experience or from history -- 70 plus years of
> "chemical munitions" use -- confirm or deny this?
>
> "No. One fire in the middle of a large area clears out the whole place.
> You don't have to shoot the tear gas near the fire, all the air around
> the fire gets sucked up from the heat and fresh air gets pulled in to
> replace it."
Just think about it for a second. There's an assumption that there's "fresh air" somewhere. A fire will create a turbulence, but if all the air around is filled with tear gas, it's not going to have much effect.
My most recent experience, in Exarcheia in 2005, didn't suggest that the burning cars and trash bins were doing much to make the experience tolerable.