By Julie Bawden-Davis
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Every year, nearly 2,500 people lose their lives to residential fires and nearly 500 people fatally succumb to carbon monoxide poisoning in the home. Installing the safety detectors in your house is a major step you can take to protect your family in case of a fire. According to the National Fire Protection Association, nearly two-thirds of fatalities that occur in home fires involve residences without working fire alarm systems.

Understanding Different Detector Types
With so many different types of carbon monoxide and smoke detectors on the market today, it can be daunting to understand the various types and capabilities when buying and installing these potentially life-saving devices for your house.

  • Ionization Smoke Alarms. The most common kind of smoke alarm works with ionization technology. This type of alarm does the best job of detecting flaming fires. These alarms sound when ionized (electrically charged) particles are released in a fire and interfere with the electrical current in the alarm.
  • Photoelectric Smoke Alarms. respond most readily to smoldering fires that produce smoke and can result in potentially deadly smoke inhalation. This type of alarm sounds when smoke particles disrupt a light beam located in the alarm.
  • Dual Sensor Smoke Alarms. Both flaming and smoldering fires are dangerous, so if possible, it's best to install both ionization and photoelectric fire alarms capabilities in your home. You can do this by installing each type, or get a dual sensor alarm that combines both technologies in the same unit.
  • Visual & Tactile Alarms. If there are individuals in the home with visual or hearing impairments, in addition to standard alarms, you should consider installing models that vibrate or flash strobe lights in the case of a fire or carbon monoxide related emergency.
  • Carbon Monoxide Detectors. A colorless, odorless gas, carbon monoxide (CO) can be poisonous to humans and animals in high concentrations. CO poisoning is especially common in winter when heaters and fireplaces are often used for warming homes. Toxic build-up of this gas is most likely in well insulated houses where there is little exchange of inside and outside air. Your best line of defense against potential CO poisoning is to install detectors in your home. There are CO detectors combined with smoke alarms, and some even have a voice feature that tells you if the threat is fire or CO. Be advised, however, if you own a combined CO and smoke alarm, it's important to determine if the smoke alarm is photoelectric or ionization, so you can get the other type and ensure your home is completely covered.
What to Look for in Smoke and CO Detectors
Choose the best smoke and CO detectors for your home by looking for the following features:
  • Test button. Choose a model that allows you to test the unit to make sure that it is in working order.
  • CO gas level sensor. Knowing how much CO is in your air will help you determine the severity of the problem and possibly pinpoint the source.
  • Battery back-up. Detectors that run on electricity need a battery back-up in case of a power outage.
  • Low battery warning. Most detectors will warn you when a battery is low so that you can replace it.
  • "End of Life" warning feature. Smoke and CO detectors all have a specified lifespan and lose sensitivity as they age. Choose a model that informs you when it's time to replace the detector. (Replace smoke detectors every five years and CO detectors every 10 years.)
  • Standard requirements. Make sure that the smoke alarms you choose meet Underwriters Laboratories Standard 217 and the CO alarms meet UL Standard 2034.
Proper Detector Installation
A detector is only as good as its placement in your home. The U.S. Consumer Product Safety Commission recommends installing smoke and CO alarms on every level of the home, including outside and inside sleeping areas. Place the alarms in the center of a ceiling or if installed on the wall, 6 to 12 inches below the ceiling. Because items such as furnaces normally let off small amounts of CO, it's best to install detectors at least 5 feet from such appliances.

Now that you know what to look for in smoke and CO detectors, you can choose the right models for your home and rest easy.


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