Buying the right type of smoke alarm for your home can be the key to escaping a fire safely

OVERLAND PARK, Kan. - To understand the types of smoke detection technologies, you have to understand there are two types of fires. Slow, smoldering fires are heavy in smoke, while fast moving fires are heavy in flames. 

"One might be like a cigarette that falls between the cushions of a sofa. That might be more like a slow, smoldering fire," explained Trisha Roberts, Public Education Specialist with the Overland Park Fire Department. "And a fast, flaming fire might be like grease catching fire on the stove and taking off quickly."

There are two types of smoke detectors: Ionization technology and photoelectric technology. Each works better in detecting a specific type of fire.

Ionization – fast moving fires

This is the smoke detector commonly found in the majority of homes. While it is designed to detect and warn you of a fast, flaming fire, a Scripps test found it is not as efficient in the event of a slow, smoldering fire. In our test, the Ionization technology took 9 minutes and 12 seconds longer to sound an alarm.

Photoelectric – slow moving fires with lots of smoke

This smoke detector is designed to detect slow moving smoke traveling through your home from the ignition point of a fire. Since smoke is the leading cause of death in a fire, this increases your chances of getting out alive.

Dual Sensing

This smoke alarm is a combination of both the Ionization and Photoelectric technologies in one unit. This is the recommendation of most major fire departments, including the City of Overland Park.

Firefighters say any smoke alarm is better than no smoke alarm. They recommend that you install dual sensing smoke detectors in your home. Having both types of technology, in good working order, in the rights locations, increases your chances of survival.

To choose the right product, look for a large "I" on the package to denote Ionization. A "P" means Photoelectirc. If you already have working Ionization smoke alarms, you can add additional Photoelectric units to protect your family. If you are installing new ones, dual sensing smoke detectors are recommended.

"We like the dual sensing smoke alarms better, because it protects you from two different kinds of fires," said Roberts. "And in a fire, every second counts. So you want the earliest notification possible."

So why do they make two different kinds of smoke alarms?  We contacted First Alert and Kidde, the makers of the most popular brands.  Each company says it is to keep consumers safe from the two different types of fires. 

Like most major fire associations around the country, they encourage you to install both types of smoke alarms in your home, or a dual-sensing smoke alarm.

The First Alert website says:  "For maximum protection, use both types of technology on each level and in every bedroom of your home." 

Kidde also recommends both types of technologies on its website.

Fire safety experts also recommend to test your smoke alarms monthly and replace batteries every six months. Some detectors are hard-wired and run on your home's electricity, but must have a battery for backup when the power goes out.

Smoke detectors should be installed on every level of your home, outside sleeping areas and in every bedroom. The best location is 4-6 inches away from walls and corners.

Finally, it is important to note that smoke alarms are not made to last forever. They have a ten year life. Even if they still sound a test alarm, fire departments and manufacturers recommend you replace smoke detectors every decade. 

Safety experts advise to check the manufacture date on the back of the alarm. If your alarm does not have a date, chances are it is over ten years old and should be replaced.

"It's such a simple thing. They don't cost that much. Even the dual sensing smoke alarm might be a little more expensive, but you're talking under $20," Roberts noted. "And for a life insurance policy, it's going to last you 10 years. That's pretty sweet."

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