New requirements for all Baltimore County rental properties went into effect on January 1, 2018, and more go into effect April 1, 2018. It depends on the number of units and configuration of the building, but generally speaking, if you have hardwired/interconnected smoke/CO (combo) detectors or hardwired/interconnected smoke detectors and 10-year lithium CO detectors on every floor of all the units you should be fine.
Concerning the interconnections there are two main options:
1. If the interconnection is hardwired you can use combo detectors.
2. If you choose wireless interconnection it is my understanding they do not make combo detectors of that type. In that case you can install hardwired/wireless interconnect smoke alarms and 10-year lithium battery-opereated CO detectors.
*** Please note that even if you use wireless interconnection smoke alarms, each alarm must be hardwired. The difference is they do not have to be hardwired to each other. CO detectors do not have to be hardwired.
New Smoke and Carbon Monoxide Alarm Regulations
A new state law regarding battery-powered smoke alarms became effective on January 1, 2018. A hardwired and battery backed interconnected smoke detector must be present and operational on every level excluding unoccupied attics, garages or crawl spaces. Wireless remote interconnection is acceptable.
Single Family Home
- A hardwired smoke detector with a battery backup must be located in the corridor or hallway outside of sleeping areas and on every level of the dwelling unit.
- If the home has a basement, a hardwired smoke detector with a battery backup must also be located in the basement, and must be interconnected to the smoke detectors on all levels of the dwelling unit.
Homes with Two or Three Apartments
- A hardwired smoke detector with a battery backup must be located in the corridor or hallway outside of sleeping areas and on every level of the dwelling unit including the basement. Basement smoke detector must be interconnected to the smoke detector on the first floor only.
Homes with Four to Six Apartments
- A hardwired interconnected smoke detector with a battery backup must be located in the corridor or hallway outside the sleeping area and on every level of the dwelling unit.
- hardwired smoke detector is required in the basement for homes with four to six apartments but does not have to be interconnected.
Carbon Monoxide Alarms:
On March 8, 2016 House of Delegates, State of Maryland, adopted House Bill 849, requiring all rental dwelling units, on or after April 1, 2018, must have a carbon monoxide alarm installed within the dwelling on every level of the unit, including the basement. The alarm can either be a hardwired combination unit or a 10 year sealed battery unit.