Which type of radiation is commonly used in smoke detectors?

Smoke detectors commonly utilize alpha particles as a part of their ionization process. Inside an ionization smoke detector, a small amount of radioactive material, typically americium-241, emits alpha particles. These alpha particles ionize the air in the detection chamber, allowing a small electrical current to flow between two electrodes. When smoke enters the chamber, it disrupts this flow of current, triggering the alarm.

Alpha particles are particularly suited for this application because they are capable of ionizing air effectively despite their limited range and penetration ability. In the context of smoke detectors, their specific characteristics make them ideal for detecting smoke and providing timely alerts. This method is reliable and practical for the designed purpose of enhancing safety in residential and commercial environments.