For optimum protection, you should install smoke and carbon-monoxide (CO) alarms that interconnect (they all sound at once) throughout your home. As a rule, smoke alarms should be installed on the ceiling or on a wall no more than 12 inches below the ceiling and away from corners, windows, and vents. Read the manufacturer's instructions. Also make a family escape plan and practice it for day and night escapes.
Place an interconnecting dual-sensor smoke alarm near the stairwell leading upstairs. And put an interconnecting CO alarm at least 20 feet from a furnace, water heater, or other fuel-burning appliances.
Kitchen and Living Area
Place an interconnecting photoelectric smoke alarm 10 feet away from—but not inside—the kitchen. Put another interconnecting dual-sensor smoke alarm and an interconnecting CO alarm in the living area. (If your home has more than 1,000 square feet per level, your local building code might require a second smoke alarm.)
Place an interconnecting dual-sensor smoke alarm in each bedroom and in the hallway. If the hall location is close to a bathroom, install a photoelectric alarm since steam can trigger nuisance alarms. And place a separate interconnecting CO alarm in the hallway.
Never put a CO alarm inside the garage, where car exhaust can trigger false alarms. Also don't put CO alarms near any windows in your house, where fresh air can have the opposite effect.
Even if your attic isn't finished, install an interconnecting dual-sensor smoke alarm.
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