What You Should Know About Smoke Alarms.

Since the late 1970s, smoke alarms have decreased fire deaths by almost 50 percent, according to the National Fire Protection Association (www.nfpa.org ). About 95 percent of American households currently have at least one smoke alarm installed. There’s no doubt smoke alarms save lives: 65 percent of reported home fire deaths occur in homes with no smoke alarms or no working smoke alarms.

There are two common types of smoke alarms used for detecting fires.

1. Ionization smoke alarms. When smoke enters the smoke alarm chamber, it disrupts the flow of ions, which disrupts the flow of current between two electrically charged plates and activates the alarm. This type of smoke alarm is generally better at detecting flaming fires. Examples of flaming fires are paper burning in a wastebasket or grease fires on the stovetop. Flaming fires are quick to spread and rapidly consume materials in their path. A study by the U.S. Consumer Product Safety Commission found that 94 percent of home fires were categorized as flaming fires.

2. Photoelectric smoke alarms. When smoke enters the smoke alarm chamber, light is reflected onto a light sensor triggering the alarm. This type of smoke detector is generally better at detecting smoldering fires. Smoldering fires can sometimes burn for hours before bursting into flames. Examples include cigarettes burning in couches or bedding.

Since you can’t be sure what kind of fire might start in your home, consider installing both ionization and photoelectric alarms on every level of your home and in every sleeping area.

Here are some other smoke alarm facts and tips.

If all homes in the United States had a working smoke alarm, an estimated 890 lives could be saved each year.
The biggest cause for smoke alarm failure is missing, disconnected, or dead batteries. The leading reason for disabling smoke alarms is nuisance activations.
If you move into a new home, unless you know that the smoke alarms are new, you should replace them with new ones.
Replace alarms in your home at least every 10 years.
Test your smoke alarms once a month, following the manufacturer’s instructions.
Replace your batteries in your alarm once a year, or as soon as the alarm “chirps,” warning that the battery is low. Make it a point to change batteries when you change your clocks as you switch from daylight saving time to standard time in the fall.
Never “borrow” a battery from your smoke alarm.
Never disable your smoke alarm. If it is sounding off with “nuisance alarms,” try relocating it farther from kitchens or bathrooms where cooking fumes and steam can set it off.
Follow manufacturer’s instructions for cleaning your alarm by vacuuming or dusting.
Remember that those who are deaf or hard of hearing cannot rely on the sound of a regular alarm to alert them to a fire.