Leviticus 13:40-43

40"If a man's hair falls out from his head, he is bald; he is clean.

41And if a man's hair falls out from his forehead, he has baldness of the forehead; he is clean.

42But if there is on the bald head or the bald forehead a reddish-white diseased area, it is a leprous disease breaking out on his bald head or his bald forehead.

43Then the priest shall examine him, and if the diseased swelling is reddish-white on his bald head or on his bald forehead, like the appearance of leprous disease in the skin of the body,