Doing a Sulphur Burn

I noticed an extremely small amount of powdery mildew on the bottom leaves of some of my plants. I chopped all of those off, and hoped for the best. I really am surprised how it got there in the first place because my humidity rarely even gets as high as 60%, and the exhaust is constantly going. Other than that, the plants look great. Since I was told that the spores are in the air, and all over the place, just clipping off the visibly affected leaves was not going to eradicate the problem. I decided to do a sulphur burn earlier today. I've had the exhaust and fans going now for a few hours to get rid of the gas and the smell, but it still lingers. I'm very wary about turning on the lights yet because of the smell, and the last thing I want to do is burn the shit out of my plants. Any advice on how much longer to wait?

Nobody's done one of these? Come on people, help me out here.

Nevermind then. I turned the lights on about 10 minutes ago, and things look like they're going to be fine. Thanks for the help everybody....LoL.