(a) Every dwelling unit shall be equipped with at least one approved smoke detector in an operating condition within 15 feet of every room used for sleeping purposes. The detector shall be installed on the ceiling at least six inches from any wall, or on a wall between four and six inches from the ceiling.
(b) Every single-family residence shall have at least one approved smoke detector installed on every story of the dwelling unit, including basements but not including unoccupied attics. In dwelling units with split levels, a smoke detector installed on the upper level shall suffice for the adjacent lower level if the lower level is less than one full story below the upper level; however, if there is an intervening door or similar partition between the adjacent levels, a smoke detector shall be installed on each level.
(c) Every structure that contains more than one dwelling unit, or contains at least one dwelling unit and is a mixed-use structure, shall contain at least one approved smoke detector at the uppermost ceiling of each interior stairwell. The detector shall be installed on the ceiling at least six inches from the wall, or on a wall between four and five inches from ceiling.
(d) (1) Except as otherwise provided in subsection 17-4(d)(2) below, it shall be the responsibility of the owner of a building or structure to supply, install, inspect, test and maintain all required detectors.
(2) In structures containing more than one dwelling unit, the owner shall be responsible for inspecting, testing and maintaining detectors in common stairwells and hallways and in other common areas. Unless otherwise agreed between the owner and the occupant, it shall be the responsibility of the occupant to inspect, test and maintain the detectors within the occupant's dwelling unit or rooming unit. Notwithstanding the foregoing, the owner shall ensure that such detectors are in operating condition at the time the occupant takes possession of the dwelling unit. In the event that a dwelling unit becomes unoccupied, the owner shall assume the duties and responsibilities of an occupant with respect to that dwelling unit. The owner shall be responsible for providing one occupant over 21 years of age per dwelling unit with written information regarding necessary testing and maintenance for all detectors in the dwelling unit.