Leviticus 13:53-55

53“But if the priest examines it, and indeed the plague has not spread in the garment, either in the warp or in the woof, or in anything made of leather,

54then the priest shall command that they wash the thing in which is the plague; and he shall isolate it another seven days.

55Then the priest shall examine the plague after it has been washed; and indeed if the plague has not changed its color, though the plague has not spread, it is unclean, and you shall burn it in the fire; it continues eating away, whether the damage is outside or inside.