מִכְוָה

When there is a burn on someone’s skin and the raw area of the burn becomes reddish-white or white,

…the priest must examine it. If the hair in the spot has turned white and the spot appears to be deeper than the skin, it is a disease that has broken out in the burn. The priest must pronounce him unclean; it is a diseased infection.

But if the spot is unchanged and has not spread on the skin but has faded, it is a swelling from the burn, and the priest is to pronounce him clean; for it is only the scar from the burn.