Ionization smoke alarms are generally more responsive to flaming fires. E.g. Grease fire in the kitchen, paper burning in a waste basket

How they work: Ionization-type smoke alarms have a small amount of radioactive material between two electrically charged plates, which ionizes the air and causes current to flow between the plates. When smoke enters the chamber, it disrupts the flow of ions, thus reducing the flow of current and activating the alarm.