Whenever conditions inside or under occupied business buildings provide extensive harborage for rats (in the opinion of the director of health) the director of health is empowered, after due notification in accordance with section 9.32.170 of this chapter, or its successor section, to close such business buildings until such time as such conditions are abated by ratproofing and harborage removal, including, if necessary, the installation of suitable concrete floors in basements, or replacement of wooden first or ground floors with concrete or other major repairs necessary to facilitate rat eradication. (Prior code § 18-22-7)