Battery-powered smoke alarm provides an early warning signal in the event of a smoke or fire incident. Special hush feature silences nuisance alarms without requiring you to remove the battery. Ionization sensor offers reliable protection against fast flaming and other types of fires. Low-battery warning signal sends an audible chirp to indicate the included battery is nearly depleted. Recommended smoke alarm locations include at least one in every floor level, one in each sleeping area, one in every room where electrical equipment is operated and one in every stairway, as stairways act as chimneys for smoke and heat.