Ionization smoke detectors use ionizing radiation to detect particles in the air. The smoke is then drawn into the detector and converted into an electrical signal. Photoelectric smoke detectors use light to detect particles in the air. The smoke is then drawn into the detector and converted into an electrical signal. Both types of smoke detectors work very well, and there is no significant difference in performance between them. The decision is based on which type of detector you prefer and which one will be more convenient for you to install.