Types and Uses of Smoke Detectors
In 2011, the U.S. Fire Administration reported that 1,389,500 fires occurred in the United States. These fires resulted in the deaths of 3,005 people and approximately $11.7 billion in losses. No matter how careful you may be when it comes to fire hazards, all homes are at risk for becoming involved in a fire. However, smoke detectors can help you make sure that both you and your family are properly warned should a fire occur.
Ionization Smoke Alarms
These types of smoke alarms contain two small plates that are electronically charged. A small amount of radioactive material sit between these two plates. The radioactive material ionizes the air between the two plates, causing the air through the device. If smoke enters the detector, the flow of ionized air between the plates is compromised, causing the alarm to be activated.
Photoelectric Smoke Alarms
These alarms utilize a light source and a light sensor. The light is aimed into a sensing chamber away from the sensor. If smoke enters the sensing chamber, the flow of light will become disrupted. The alarm is triggered when the disrupted light hits the sensor.
Why are there Different Types of Smoke Detectors?
Many homeowners do not realize that there are two different types of fires: smoldering fires and flaming fires.
- Flaming Fires: These fires occur when a gas catches on fire, resulting in a visible flame. These fires tend to be hotter and are more likely to spread much more rapidly than smoldering fires.
- Smoldering Fires: These fires begin when there is a weak heat source. They often begin slowly on the surface of an object and with little or no flames. For example, residential smoldering fires can be caused by lit cigarette ash falling onto fabric furniture. While they may cause significantly less damage if caught early, they also emit toxic gases, such as carbon monoxide, at a much faster rate that flaming fires.
Ionization smoke detectors and photoelectric smoke detectors detect different types of fires. Ionization detectors are far better at detecting flaming fires, while photoelectric detectors are far better at detecting smoldering fires.
Which Smoke Alarm Should be Used?
It is very difficult, if not impossible, to predict which type of fire may occur in your home. It is highly recommended that homeowners install both types of smoke detectors throughout the home. In some cases, the two types of smoke detectors can be connected; if one alarm is triggered, the other alarm will also be triggered.