Section 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.