Accidental fire can occur anytime and at anyplace. A smoke detector can save lives, so it shouldn't be taken lightly. All smoke alarms should be tested at least once a month to make sure they operate properly. If it is battery operated, replace the batteries at least once a year to make sure the alarm will work when it is needed. Smoke alarms have a useful life of about ten years. At that age they should be replaced, even if they seem to be working.
Combination Ionization and Photoelectric Sensor combine both sensors into a single alarm. The combination of these two sensing technologies provide the best overall fire protection.
Ionization Detectors react faster to open flaming fires and are usually the least expensive. The ionization type detector is sensitive to small smoke particles, it will respond more quickly to cooking and gases.
Photoelectric Detectors react faster to smoldering fires such as a smoldering mattress and are less likely to react to cooking.