When To Turn The Lights Off

That depends on the type of bulb. Fluorescent bulb - Leave it on if you will need it again within 20 minutes. Incandescent bulb - Turn it off when not in use for over a few minutes. This is based upon the fact that incandescent bulb life is not significantly effected by turning it on/off whereas the fluorescent bulb life is reduced each time it is turned on. Additionally, repeated starting of fluorescent ballasts reduces the fluorescent life span as well as uses more energy. - Jim Hoyle