Detector location/type/Requirements for Home Sellers

Detector location: You must install gas leak and carbon monoxide detectors on each level of your home. On levels with sleeping areas, your gas leak and carbon monoxide detectors must be within 10 feet of bedroom doors. Attics and basements do not require detectors unless you use them as a living space.

Detector type: Your gas leak and carbon monoxide detector could be battery-powered with battery monitoring, plug-in with a battery backup, hard-wired with a battery backup, low-voltage with secondary power or a qualified combination of a smoke detector and gas leak and carbon monoxide detector alarm. 

Detector requirements for home sellers
If you are selling your home, you will need to obtain a certificate of compliance for your gas leak and carbon monoxide detectors. This certificate ensures your home has the proper detectors before the buyer moves in. Check if you need to replace your detectors/alarms, update as necessary and contact your local fire department to set up an inspection.