(1) The establishment or facility must be of sound construction and kept in good repair, and must be of such construction as to prevent the entrance or harboring of vermin.

(2) The doors, windows, skylights and other outside openings of the establishment or facility, except receiving rooms and feeding rooms, must be protected against the entrance of flies and other insects by properly fitted screens or other suitable devices.

(3) Outside doors, except receiving rooms and feeding rooms, must be so hung that not over 1/4 inch clearance remains when closed. Screen doors must open toward the outside of buildings. Doors must be provided with self-closing devices where necessary to prevent entry of vermin into processing and storage rooms.