BALTIMORE COUNTY SMOKE DETECTOR INSPECTION
A hardwired smoke detector with battery backup must be located on every level and interconnected so all alarms go off at the same time. Whatever level has a bedroom, that hard wired smoke detector must be in the corridor or hallway outside of the sleeping area.
BALTIMORE CITY SMOKE DETECTOR INSPECTION
If the property was built or rehabilitated after 1988 a hardwired smoke detector with battery backup must be located on every level and inside every bedroom and must be interconnected so all alarms, go off at the same time.
If the property was NOT built or rehabilitated after 1988 and is not already hardwired, a smoke detector is required on every level and in every bedroom. These units can be battery powered by a 10-year, sealed lithium battery only. 9 volt and AA units will fail the inspection.