In 2016, the Maryland General Assembly passed House Bill 0849 and its companion Senate Bill 0182. Both bills require the installation of carbon monoxide alarms for any new and existing rental dwelling units, including rental properties that are exclusively powered by electricity. This includes any type of dwelling unit that can be rented to an individual or family.

The Montgomery County Council passed Bill 23-18 which took effect on July 1, 2019 requiring Carbon Monoxide Alarms in all existing residential dwellings that have fuel (oil, gas, kerosene, propane etc.) or wood burning appliances such as a fireplace, or an attached garage.

Carbon monoxide alarms must be installed outside of each sleeping area and on every habitable level of the dwelling to include the basement. Combination smoke and carbon monoxide detectors that are electrically hard wired, have a battery backup, and were manufactured less than 10 years ago are legally acceptable. These laws are enforced by the Department of Housing and Community Affairs, Housing Code Enforcement Unit.

To file a complaint about a residential rental dwelling without a functional Carbon Monoxide detector, please see the topic entitled "Housing Complaints" or online users may click on the first link below.