Smoke Detectors

Most fires occur at night, while people are sleeping. A smoke detector can alert you when there is a fire, in time to save your life. Smoke detectors work by sensing rising smoke from a fire and sounding an alarm.

Types of Smoke Detectors
Photoelectric - Projects a beam of light. The alarm is activated when the beam is interrupted by smoke. 
Ionization - Chamber contains a small, safe radiation chamber source that produces electrically charged air molecules.

Both types of detectors are equally effective and neither requires you to be familiar with its inner workings. As long as you buy a detector tested by a major testing laboratory, such as Underwriters Laboratories (UL), you can be assured it has met certain testing requirements.

Detectors can be powered by battery or by household current. Battery powered detectors are easiest to install and require no outlets or wiring connection, however, batteries must be replaced twice a year. We recommend changing them in the spring and in the fall when you change your clocks. All UL listed battery operated detectors sound a trouble signal when replacement is needed. This signal usually lasts seven days, so it is advised to check the detector following extended periods away.

Detectors powered with household current should be wired permanently into your home's electrical system. The type with battery backup is best. 

Smoke rises, so the best place to install a smoke detector is on the ceiling, or high on an inside wall, six to eight inches below the ceiling. The Fire Department is available to show you the best places to install smoke detectors in your home.

For information on installation of smoke detectors in compliance with the City of Webster Groves Housing Code, visit the department of 
Planning and Development.   

Caring for Smoke Detectors
Dirt, extreme changes in temperature, and cooking exhaust can cause a false alarm or malfunction of the detector. To prevent false alarms, install the detector away from air vents, air conditioners, and fans. Keep the grillwork free of dirt with occasional vacuuming and dusting. Don't paint the cover of the detector, as this may clog the grillwork. Test your detector using the test button every month.