Ionization alarms are a type of smoke detector that use a small amount of radioactive material to detect smoke particles in the air. When smoke enters the alarm, it disrupts the flow of ions, triggering the alarm to sound. These alarms are particularly effective at detecting fast-flaming fires, such as those caused by paper or wood. Unlike photoelectric alarms, which use a light beam to sense smoke, ionization alarms respond more quickly to certain types of fires. It's important to have both types of alarms in your home for comprehensive fire safety. Regular testing and battery replacement are essential to ensure they work properly.