Hi Kate. We had base board heat when my 4 y/o was a baby. I put furniture in front of them. Her crib in front of the one in her room, the couch in the living room. The heat was able to get out and she wasn't able to reach them. However, in places like the bathroom, there wasn't anything I could do. She only put her little hand inside it ONE time. For alot of things I feel that the only thing you can do it let the little ones learn first hand not to do something. I would constantly tell her 'thats a no no' from the start. Also, if u cover the heater with anything besides metal, it will be a fire hazard, if you cover it with metal the metal would get just as hot. I would also turn the heat down or off in that room if possible. Best of luck!