if by interrupt u mean some light comming from the hall when u open the door, or a small light that my be on the fan, i dont think it wil coz u problems. There should be no REAL light comming in. Like u deside to switch on ur hps to see how ur plants doing coz u cant sleep LOL or light comming from a window in the morning

and yes i am pretty fuckin stoned coz i just read what i wrote an i was like "what the fuck..." LOL