N.Y.C. Admin. Code § 27-2012: § 27-2012 Cleaning of interior of dwelling units.

a. The occupant of a dwelling shall maintain the dwelling unit which he or she occupies and controls in a clean and sanitary condition except as provided in subdivision b of this section.

b. The owner of all rooming units in a rooming house or an entire multiple dwelling used for single room occupancy, or the person in control of an apartment containing rooming units, shall clean any such unit before any change in occupancy and at least once a week during the period of occupancy and shall at all times maintain the same in a clean and sanitary condition.