An approved smoke detector shall be installed outside the sleeping areas in each dwelling unit.  All smoke detectors should be ceiling mounted with additional detectors located on each habitable level, including the basement.
   (A)   In 1-, 2-, and 3-family dwelling homes these smoke detectors may be battery operated and single station type.
   (B)   In 4- and 5-family dwelling homes the smoke detectors within the dwelling units may be single station type.  Upon the sale or transfer of such property, the smoke detectors that are required on all hallway levels or suitable locations and in the basement shall be permanently wired and shall be interconnected, so that when one sounds all sound.  It shall be the responsibility of the property owner to install and to maintain these systems and they shall be tested annually by a competent person who shall notify the Fire Department in writing of such test.  Plans for these systems shall be approved by the Head of the Watertown Inspector of Buildings before installation.
(1982 Code, Ch. IX, § 4)  Penalty, see § 92.99