the judge was initially pushing me to provide an empirical basis, but in the end she shifted the burden of proof to them, which is actually in accordance with the existing case law: the premise of second hand smoke affecting my enjoyment of the premises is a purely subjective/experiential thing, by definition, so it falls on them to demonstrate that the air is free of smoke if they wish to justify their interference with my enjoyment of the space. it's the correct legal answer to the question, as i posed it.

so, i'm allowed to run the fan unless they can prove i'm making the whole thing up.