Oregon Revised Statutes Protection from Fire § 479.270

(1) The owner of any rental dwelling unit or the owner's authorized agent shall be responsible for supplying, installing and maintaining the required smoke alarms or smoke detectors and shall provide a written notice containing instructions for testing of the devices. The notice shall be given to the tenant at the time the tenant first takes possession of the premises.

(2) The duty of the owner or authorized agent of the owner to maintain the required smoke alarms or smoke detectors, including providing working batteries, arises only:

(3) Supplying and maintaining a smoke alarm or smoke detector under ORS 479.250 to 479.305 shall be considered a habitable condition under ORS 90.320.