Leviticus 13:28-31
English Standard Version
29"When a man or woman has a disease on the head or the beard,
30the priest shall examine the disease. And if it appears deeper than the skin, and the hair in it is yellow and thin, then the priest shall pronounce him unclean. It is an itch, a leprous disease of the head or the beard.
31And if the priest examines the itching disease and it appears no deeper than the skin and there is no black hair in it, then the priest shall shut up the person with the itching disease for seven days,