Home Smoke Detector Types

Photoelectric

• Photoelectric smoke detectors contain sensors into which continuous light beams shine. When smoke interrupts or magnifies the light beam, it triggers the sensor to sound an alarm, according to FireSafety.gov. The National Fire Protection Association reports that photoelectric detectors best warn of long-smoldering fires.

Ionization

• Ionization smoke detectors contain a small amount of radiactive material that cause an electric current between two metal plates. If smoke interrupts the small current, the sensor trips, sounding an alarm. The National Fire Protection Association concludes ionization detectors function best in cases of fires involving high flames.

Combination Detectors

• Because photoelectric and ionization detectors exhibit strengths and limitations, fire safety groups including FireSafety.gov recommend smoke detectors incorporating both types of technology. Such combination detectors are available at hardware stores and retail outlets.

Battery Operated

• Batteries remain the most common power source for smoke detectors. Battery-powered detectors are most common in older homes predating the common use of hard-wired detectors. Battery-fueled detectors require regular maintenance to check for dead batteries but are cheaper than retrofitting older houses with hard-wired detectors.

Hard-Wired

• Many modern home builders hard-wire smoke detectors into the electrical systems of the dwellings. These detectors often contain battery backups to continue protecting homes in cases of power outages.