What Makes Smoke Detectors Beep?

Statistics

• According to Fire Safety for Citizens, dying from fires and related burns ranks 5th in the United States for people who die from unintentional injuries. A 2006 report states that in the United States a person dies in a fire every 162 minutes. Because most fires start at night, smoke inhalation is typically what causes death. Smoke detectors are a vital home safety device, and maintaining them is equally as important. The detector will emit a beeping sound that often increases in frequency when the detector has a low battery.

Types

• Smoke detectors generally work on two different principles. One type is called ionization. It works by using a small amount of radioactive material. An electrical current runs between two electrodes, and when smoke crosses the current, the alarm sounds.

  The other way a smoke detector works is called photoelectric. With this type, a beam of light that is invisible to human detection is emitted. When smoke is present, it disturbs the light beam and the alarm sounds.

  Both types will emit a beeping sound when the battery is low, warning the homeowner to replace the battery.

Features

• Some detectors are wired into the electrical system of the home, while others run off of batteries. However, the electrically wired devices typically have a battery back-up. Even for devices that are electrically wired, when the battery is weak, the detector emits a beeping sound to alert the homeowner to replace the battery.

Prevention/Solution

• The beeping sound, as opposed to the alarm sound, is a warning that the batteries are low and the unit is slowly losing functionality. A best practice is to regularly test the smoke detector before the beeps begin. Typical smoke detector manufacturer's guidelines recommend testing the detectors once a week. Detectors are equipped with a test button to ensure that they are functional. The Ray Town Fire Protection District of Missouri recommends changing the battery whenever you change your clock. They also recommend using a vacuum cleaner to remove accumulated dust and dirt from the unit. At a minimum, batteries in smoke detectors should be replaced every year.

Significance

• According to Fire Safety for citizens, "In 2006, residential fires caused nearly $7 billion in property damage." Smoke detector costs start as low as $5. For a life-saving device, this is a very reasonable price. When purchasing a smoke detector, check that it has an Underwriters Laboratories (UL) label. This label ensures that it has been tested.

  Equally as important is to test the smoke detector and replace the batteries often. The beeping sound it emits is an important feature; however, it is best to test before the batteries get weak enough to beep in warning.