At least one detector right outside the kitchen and one detector near every bedroom. If you have muliple bedrooms that are close together, then one detector centrally located near the rooms will do.
Smoke alarms should be installed in every bedroom, outside every sleeping area that may be away from a bedroom, and on every level of the home, including the basement. Interconnect all the smoke alarms so that when one alarm sounds, all of them will sound. Smoke alarms use one of two technologies, ionization, which is more responsive to flaming fires, or photoelectric, which is more responsive to smoldering fires. You can obtain smoke alarms which uses one, or both technologies. Follow the manufacturer's instructions for installing them, which will be on ceilings or high on the walls.
Install carbon monoxide (CO) alarms if you have any appliances that burn a fuel, including cooking and heating/drying equipment, or if you have a garage attached to your home. Install them in a central location outside each sleeping area and on every level of the home. Check for any laws, codes or standards that may require they be installed in additional areas. Interconnect all CO alarms so that when one sounds, all of them will sound.
Test smoke and CO alarms monthly, replace any batteries once a year unless the manufacturer tells you differently, and replace all alarms in accordance with the manufacture's recommendations, because they don't last forever.
Our local ordinance requires only that each bedroom has a fire alarm, but I'm hoping to be able to purchase a few more when I get extra money, even though limited. Check with the city officials, fire dept. as to what is required for your area, for your safety, and for your family. God bless you.
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