(b) upon the occurrence of a vacancy, replace or properly equip any
such device which has been removed or rendered inoperable, so as to
provide operational smoke detecting devices for any new tenant; and
(c) notify tenants in writing, individually or through posting of a
notice in a common area of the building, of the respective duties of
owners and tenants under this section.
5. Except as provided in paragraph (b) of subdivision three of this
section, the tenant shall keep and maintain any smoke detecting device
installed pursuant to this section in good repair and replace any such
device which becomes inoperable during his occupancy.
6. An owner need not furnish or install a smoke detecting device where
one has already been installed, provided that (a) the type of such
device and the manner of its installation comply with the provisions of
this section and the standards prescribed by the state fire prevention
and building code council, (b) the existing device is tested and found
to be operational, and (c) the existence of such device in lieu of an
owner-furnished device is noted on the records kept by the owner
pursuant to paragraph (c) of subdivision three of this section.