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Smoke Alarms
Smoke alarms save lives! It is the single most valuable lifesaving device you can have in your home. An operable smoke alarm more than doubles your chances of surviving a fire.

The Alarm Program began in 1988 with the Charleston Fire Department supplying and installing smoke alarms for the elderly. handicapped, and low-income residents of the city. Now, smoke alarms are provided to any citizen who needs one. Department personnel also visit schools, community events, and often check door-to-door to ensure residents have an operable smoke alarm. As a result, the department installs and provides annual follow-up inspections on hundreds of smoke alarms each year.

To have a free smoke alarm installed in your house, please contact the Charleston Fire Department at 843-720-1981.

  • Roughly two-thirds of home fire deaths happen in homes with no smoke alarms or no working smoke alarms. About one in five smoke alarm failures was due to dead batteries.

  • Working smoke alarms cut the risk of dying in reported home fires by half.

  • In fires considered large enough to activate a smoke alarm, hardwired alarms operated 91% of the time, while battery-powered alarms operated only 75% of the time.


Smoke "alarms” usually refers to a type of device typically found in the home. It is a stand-alone device, typically powered by a 9 volt battery, which detects smoke and provides an alarm. Smoke “detectors” refers to a device that is part of a fire alarm system; it detects smoke but requires other devices to generate an alarm.


There are two kinds of smoke alarms, photoelectric and ionization. Both are suitable for use in your home.

  • Photoelectric alarms are the most reliable for smoldering fires which may occur in bedrooms or sitting rooms.
  • Ionization alarms are the most reliable for detecting flaming fires, which may occur in the kitchen or garage.
  • Combination smoke alarms featuring both photoelectric and ionization technology also are available.


  • Smoke alarms frequently are set off by bathroom steam or cooking vapors. Rather than take the battery out of your alarm, do the following:

  • Quiet the alarm by pushing the “HUSH” button, if equipped.
  • Open windows and turn on vent fans to clear the air.
  • Consider relocating the alarm farther away from the cooking area or bathroom.
  • Consider installing a photoelectric or combination photoelectric/ ionization type alarm. The photoelectric and combination type alarms are less sensitive to cooking smoke.

  • Tested and labeled by a recognized testing laboratory.
  • Powered by household current and include battery backup.
  • Recordable voice announcement features may be helpful in waking children.
  • Strobe light features are available for people who are deaf or hearing impaired.

  • Install smoke alarms in every bedroom, outside each separate sleeping area and on every level of the home, including the basement. Interconnect all smoke alarms throughout the home. When one sounds, they all sound.
  • An ionization smoke alarm is generally more responsive to flaming fires, and a photoelectric smoke alarm is generally more responsive to smoldering fires. For the best protection, both types of alarms or a combination alarm (photoelectric and ionization) should be installed in homes.
  • Test alarms at least monthly by pushing the test button.
  • Smoke rises; install smoke alarms following manufacturer's instructions high on a wall or on a ceiling. Save manufacturer's instructions for testing and maintenance.
  • Replace batteries in all smoke alarms at least once a year. If an alarm “chirps”, warning the battery is low, replace the battery right away.
  • Replace all smoke alarms, including alarms that use 10-year batteries and hard-wired alarms, when they are 10 year old or sooner if they do not respond properly.
  • Be sure the smoke alarm has the label of a recognized testing laboratory.
  • Alarms that are hard-wired (and include battery backup) must be installed by a qualified electrician.
  • If cooking fumes or steam sets off nuisance alarms, replace the alarm with an alarm that has a "hush" button. A "hush" button will reduce the alarm’s sensitivity for a short period of time.
  • An ionization alarm with a hush button or a photoelectric alarm should be used if the alarm is within 20 feet of a cooking appliance.
  • Smoke alarms that include a recordable voice announcement in addition to the usual alarm sound, may be helpful in waking children through the use of a familiar voice.
  • Smoke alarms are available for people who are deaf or hard of hearing. These devices use strobe lights. Vibration devices can be added to these alarms
  • Smoke alarms are an important part of a home fire escape plan.


  • Choosing the correct installation location and performing routine testing is critical to ensure your family’s safety.

  • Install smoke alarms on every level of your home, including the basement, making sure that there is an alarm outside every separate sleeping area. New homes are required to have a smoke alarm in every sleeping room and all smoke alarms must be interconnected.
  • Hard-wired smoke alarms operate on your household electrical current. They can be interconnected so that every alarm sounds regardless of the fire's location. This is an advantage in early warning, because it gives occupants extra time to escape if they are in one part of the home and a fire breaks out in another part. Alarms that are hard-wired should have battery backups in case of a power outage, and should be installed by a qualified electrician.
  • If you sleep with bedroom doors closed, have a qualified electrician install interconnected smoke alarms in each room so that when one alarm sounds, they all sound.
  • If you, or someone in your home is deaf or hard of hearing, consider installing an alarm that combines flashing lights, vibration and/or sound.
  • Follow the manufacturer’s installation directions. Typically, mount smoke alarms high on walls or ceilings (remember, smoke rises). Ceiling mounted alarms should be installed at least four inches away from the nearest wall; wall-mounted alarms should be installed four to 12 inches away from the ceiling.
  • If you have ceilings that are pitched, install the alarm near the ceiling's highest point.
  • Don't install smoke alarms near windows, doors, ceiling fans, or ducts where drafts might interfere with their operation.
  • Never paint smoke alarms. Paint, stickers, or other decorations could keep the alarms from working.
  • Make sure everyone in your home can recognize and be awakened by the sound of the smoke alarm. Some children and the elderly may not readily awake to the sound of the smoke alarm. Consider installing interconnected smoke alarms so that when one alarm senses smoke and sounds, they are all triggered throughout your home. Installing an alarm in each bedroom increases each person’s proximity to a sounding device. If someone in your home is hearing-impaired, consider smoke alarms that use visible notifications, such as flashing strobe lights.


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