Leviticus 13:56

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

55Then the priest shall examine it, after the plague is washed; and behold, if the plague hasn’t changed its color, and the plague hasn’t spread, it is unclean; you shall burn it in the fire. It is a mildewed spot, whether the bareness is inside or outside.

56If the priest looks, and behold, the plague has faded after it is washed, then he shall tear it out of the garment, or out of the skin, or out of the warp, or out of the woof;

57and if it appears again in the garment, either in the warp, or in the woof, or in anything of skin, it is spreading. You shall burn what the plague is in with fire.

58The garment, either the warp, or the woof, or whatever thing of skin it is, which you shall wash, if the plague has departed from them, then it shall be washed the second time, and it will be clean.”