Because food is an important part of holiday celebrations, careful attention to the way it is served will help ensure that guests do not become victims of food poisoning. A thermometer that registers in that zone is a wise investment.
Restaurant inspectors use a convenient dial thermometer that is fairly inexpensive.
Also, hold hot food in the oven before transferring it to the buffet table. Keep cold foods cold by placing them on ice on the serving table. And be sure to leave them in the refrigerator until you're ready to serve them. Serve small quantities of food and plan to replenish containers frequently. Avoid adding fresh food to leftovers that may have been held at an unsafe temperature.