As soon as my light went off I entered the chamber to see how much, if any, light was leaking through the vent flaps. To my amazement...barely any, if at all. I think, just to be safe I will add a piece of cloth or something that is a bit larger than the vent opening so the vent stays down but is light enough to let fresh air through. My exhaust fan stays on all the time. Should my exhaust fan be off when my light is off?