Leviticus 14:36-40

The priest shall then command that they empty the house before the priest goes in to look at the spot, so that everything in the house need not become unclean; and afterward the priest shall go in to look at the house.

So he shall look at the spot, and if the spot on the walls of the house has greenish or reddish depressions and appears deeper than the surface,

the priest shall come out of the house, to the doorway, and quarantine the house for seven days.

Then the priest shall return on the seventh day and make an inspection. If the spot has indeed spread on the walls of the house,

the priest shall order them to pull out the stones with the spot on them and throw them away at an unclean place outside the city.