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.
Codes where I live require them in the bedrooms and the hall.
If I were installing these where I am staying, I would put them in the bedroom, the kitchen, and by the gas water heater. If you happen to have a fireplace, I would put one in that room, too.
I would suggest to install smoke detectors in the bedroom and bathroom. Fire occurs most often in and from the bedroom. Many people smoke in the bathroom.
Just outside of kitchen, and high in stairwells.
A smoke detector can alert you of a fire with an alarm loud enough to wake even the soundest sleepers. They work by sensing rising smoke and heat, and save many lives each year. It's important to install smoke detectors near sleeping areas, on every level of your home, and in hallways. Consider placing a smoke detector in your garage as well. Avoid installing a smoke detector in the kitchen, or near doors or windows. Drafty locations could blow the smoke away from the smoke detector and prevent it from doing its job.
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