In which type of detector are the operational principles independent of one another?

Combination detectors integrate multiple sensing technologies to detect smoke and heat, which enhances their effectiveness in identifying fires. The operational principles of each sensing technology within a combination detector function independently. For instance, a photoelectric sensor and an ionization sensor can simultaneously monitor their respective detection parameters without influencing each other's performance. This independence allows the combination detector to provide a broader range of fire detection capabilities while maintaining reliability across different conditions.

In contrast, photoelectric detectors primarily rely on light-scattering principles, while ionization detectors use radioactive materials to detect smoke particles. Multi-criteria detectors, although they employ multiple sensing technologies, are designed to combine those principles to improve detection efficacy, rather than maintain their independence.