[fuzzfactor]

True, but simply using a low volume exhaust like a bathroom fan can give you a phenomenally greater effect than zero.

And that's for the entire house, zero is such a small number.

Then when you run it 24/7 it's 24 times as effective compared to a single hour. That's an impressive multiple itself, on top of bumping the baseline above zero to begin with.

This can really add up to a lot more ventilation than commonly assumed from some of the crummiest fans.

If you can't tell the difference when you walk in, between zero and running one of these all day before you get there, you're gonna need a bigger fan.

But you may be surprised and you never know until you try.