An Introduction to Smoke Detectors

Importance of Smoke Detectors

• A smoke detector's purpose is a simple one, to give you ample notification in case of a fire in your house. Without a smoke detector, by the time you realize that there is a fire, your house could be so badly engulfed that you cannot find a safe exit or the smoke can be so overwhelming that you suffocate trying to get out. The National Fire Protection Association reports that while 75 percent of homes have at least one working smoke alarm, between 2003 and 2006, 66 percent of fire deaths happened in homes with no working smoke alarm.

How Smoke Detectors Work

• There are two main kinds of smoke detectors: photoelectric sensors and ionization sensors. Photoelectric sensors generate a beam of light focused on a light-sensitive cell, enclosed in the alarm. If the light beam is interrupted from smoke entering the detector, the alarm goes off. Ionization sensors work by having a small piece of radioactive material create an electric current between two plates. If smoke or hot air enters the chamber, the reaction is changed and the current is disrupted, causing the alarm to go off. Photoelectric smoke detectors work best with slow, smoky fires and ionization detectors work best with quick, hot fires.

Installing Smoke Detectors

• You should install smoke detectors in every bedroom, in a hallway outside each sleeping area and at least one on every floor of the house, including the basement. Have each smoke detector interconnected with wires, so that when one goes off they all go off. Install both types of smoke detectors throughout your house, or purchase a combination detector that uses both technologies. Always install smoke detectors high on wall or on ceilings, as smoke will rise when it is created. If your home includes someone who is hard of hearing, install a detector made specifically for him as it has flashing lights and vibrates on the wall.

Maintaining Smoke Detectors

• Every smoke detector has a test button, and you should press the test button to hear the alarm once every month to ensure the battery hasn't run out. If your alarm starts to chirp on its own, replace the battery right away. The National Fire Protection Association found that in 23 percent of fire deaths from 2003 to 2006, there was a fire alarm present that wasn't in working order.