In stairways with no doors at the top or bottom, position smoke detectors anywhere in the path of smoke moving up the stairs. But always position smoke detectors at the bottom of closed stairways, such as those leading to the basement, becuase dead air trapped near the door at the top of a stairway could prevent smoke from reaching a detector located at the top. Don't install a smoke detector too near a window, door, or forced-air register where drafts could interfere with the detector's operation. Installation Most battery-powered smoke detectors and detectors that plug into wall outlets can be installed using only a drill and a screwdriver, by following the manufacturer's instructions. Plug-in detectors must have restraining devices so they cannot be unplugged by accident.
Detectors can also be hard-wired into a building's electrial system.
Hard-wired detectors should be installed by a qualified electrician. Never connect a smoke detector to a circuit that can be turned off by a wall switch. False Alarms Cooking vapors and steam sometimes set off a smoke detector. To correct this, try moving the detector away from the kitchen or bathroom, or install an exhaust fan. Cleaning you detector regularly, according to the manufacturer's instructions, may also help.