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Studies show that 60 to 80 percent of fire fatalities are attributed to either a non-functioning smoke detector, or no smoke detector at all. The presence of a working smoke detector is the first and most important step in child safety.
Types of smoke alarms Photoelectric smoke detectors: These work by directing a LED light into a dark chamber containing a photo cell, which is a light sensitive electrical component. When smoke enters the chamber it scatters the light, which then strikes the photo cell. When the photo cell’s voltage reaches a pre-determined level, the alarm sounds. Photoelectric smoke detectors tend to be better at sensing large, slow rising particles which are typical of smoldering fires. They are slower to recognize the near invisible particles released in a hot, fast burning fire.
Ionization smoke detectors: These contain a small amount of radioactive material (generally 1 microgram or less of Americium 241, far too little to pose any risk to health by radiation), which ionizes the air within the sensing chamber. This gives it an electric charge that will conduct a current. When smaller more invisible smoke particles enter the chamber and disrupt the current, it sounds the alarm.
We strongly recommend that families purchase newer smoke detectors which contain both photo- electric and ionization sensors. Fire fighters have reported showing up to house fires in which a fire was ravaging the home. Despite having “working” smoke detectors, no fire alarms were sounding, because the home happened to have the wrong type of alarm - a slow, smoldering fire was not detected by the ionization detectors, or vice versa. This is too important of a threat to your family to ignore. If you do not have combination detectors, you should work both types into your system. It is recommended you have at least 1 ionization detector, either on the main level of your house, or outside the sleeping areas, with the rest being photoelectric.
Checking the batteries in your smoke alarm
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