Leaving your groceries in the car while you stop to visit a friend may cause spoiling to start. If the food has been left out longer than that amount of time, don't even bother keeping it. In the dorm, other equipment can drain current from the electrical circuit, causing a longer cooking time. Refrigerate all carry-outs including pizza, fried chicken and Chinese food as soon after serving as possible. Never store food on the window ledge, even if the weather is cold outside.
Buildings radiate heat, making the sill warmer than the outside temperature.
These precautions should lower the risk of food-borne illnesses.