How far does furniture have to be from the side of a baseboard heater? My bookcase will be 2 inches from the side of the baseboard heater, I would like it to be closer so I can use the outlet on the other side of the bookcase but will settle for 2 inches if I have to. Is that safe? I can only find information on how far curtains have to be away or something in front of heater but not from side. Thanks!