Smoke alarms detect fires using either ionization or photoelectric sensors. There are several different types of smoke detectors available, and some are better at detecting certain kinds of fires than others.
Ionization sensors are best at detecting fast, flaming fires -- such as those fueled by paper or flammable liquids -- and are commonly used in kitchens. Ionization smoke detectors are the most affordable option at about $20 to $30 per alarm. Photoelectric sensors, on the other hand, are better at detecting slow, smoldering fires; photoelectric smoke detectors generally cost between $20 and $40 per unit.
Interconnected smoke detectors may use either ionization or photoelectric sensors, but these models have an additional feature: They connect with other smoke detectors located in a home, meaning that when one alarm sounds, they all do. This feature alerts those in other parts of the home about potential hazards sooner, increasing the likelihood of escaping safely. Interconnected smoke detectors are a bit more costly than single units ($30 to $50 per unit).
Finally, dual-sensor smoke detectors come equipped with both ionization and photoelectric sensors. Experts generally agree that a combination of the two will offer the best protection. Whether there's a smoldering fire or active flames in the kitchen, for instance, a dual-sensor smoke detector in the vicinity should adequately detect the danger.
The best smoke detectors are reliable, durable and easy to use. Ideally, you want a smoke detector that will alert you fast enough for you and your family to safely escape the home. Beyond reliability, we look for smoke detectors that are easy to install, test and silence in the case of a false alarm. To determine the best smoke detectors, we consulted reviews conducted by consumer testing organizations, including Choice magazine, Consumer magazine and ConsumerReports.org. We also evaluated owner-written reviews on sites including Amazon.com, Lowes.com and HomeDepot.com.