Even though a baseboard heater has a temperature of 150 - 180 degrees, it is very difficult to get burned on it. Since the element is covered by aluminum fins, the fins spread the heat and dissapate it very rapidly. In addition, since you are not burned instantly like a poured liquid, you would have to hold your hand on the element for a period of time to get burned. Most people (including children) remove their hands or body parts before that critical burn time is reached, since your body does it automatically. The difference with hot liquids is, the heat transfer is immediate and cannot be removed. A layer of water remains on contact with the skin.