111:1 On the night before erev Pesach, we search for chometz. One must check as soon as it becomes dark (meaning immediately after the stars come out – Mishnah Brurah 431:1). It is forbidden to start to eat (a meal; a snack is okay – MB 431:6) or to do any work starting half an hour before nightfall. (If one started earlier, he must stop once the stars come out – MB 431:12.)
111:2 We search for chometz using a single wax candle, not one that is plaited because it is like a torch. (If one did search using a torch, he must repeat the search – MB 433:10.) In a case of need, if one does not have a wax candle, then he may use one made of tallow.