What Type Of Smoke Detector Should I Buy?
With the various types of smoke detectors on the market, how do you know what to buy? Please keep one thing in mind: ANY smoke detector is better than none at all! There are four general types of smoke detectors: Ionization or Photoelectric and house current or battery powered.

With an ionization smoke detector, a small and carefully shielded bit of radioactive material "ionizes" the air in the detector's smoke chamber. When a particle of smoke drifts into the chamber, it reduces the electrical current flow. When enough particles enter the chamber, the electrical current drops below the acceptable threshold, and the detector circuit turns on the horn or buzzer.

The other most frequently purchased type of home smoke detector uses the photoelectric principle. It detects smoke by "seeing it" in much the same way your eyes do-by means of light reflected by the particles of smoke.

Because they sense the light reflected by smoke particles, photoelectric smoke detectors detect larger particles more readily than they sense the invisible particles to which the ionization detectors respond. It happens that cooler, smoldering fires produce more of these large particles than do hot, blazing fires. So, photoelectric detectors are somewhat more likely to give the alarm while a fire is still smoldering. Either kind of detector has a high probability of giving you enough warning for a safe escape.

House Current or Battery Powered: Which is Better? That depends on where you plan to put your detector, how likely you are to test it regularly, and even the likelihood of power failures where you live.

Smoke detectors which operate on batteries tend to take less time and fewer tools to install. The most effort is devoted to physically attaching the detector to the ceiling. The owner simply slips in a battery, tests the unit, and the job is done. In about a year the detector will begin to emit "beeps" every minute or so to tell the owner that the battery has begun to fall below a safe minimum of power and should be replaced.

Smoke detectors which operate on household electric current have the power they need to operate as long as there is current in the circuit to which they are connected. However, installation is more complicated with these units. In the event of power failure, detectors which operate on household electric current will become inoperable (except for those equipped with a back-up battery). If power outages are frequent where you live, you might think twice about depending only on this type of smoke warning device.