ORS 90.316: Carbon monoxide alarm.

(1) Unless a dwelling unit contains one or more properly functioning carbon monoxide alarms installed in compliance with State Fire Marshal rules and with any applicable requirements of the state building code when a tenant takes possession of the dwelling unit, a landlord may not enter into a rental agreement creating a new tenancy in the dwelling unit if the dwelling unit:

      (a) Contains a carbon monoxide source; or

      (b) Is located within a structure that contains a carbon monoxide source and the dwelling unit is connected to the room in which the carbon monoxide source is located by a door, ductwork or a ventilation shaft.

      (2) The landlord shall provide a new tenant with alarm testing instructions as described in ORS 90.317.

      (3) If a carbon monoxide alarm is battery-operated or has a battery-operated backup system, the landlord shall supply working batteries for the alarm at the beginning of a new tenancy.