Flame detectors are a type of fire detection device that uses optical or infrared technology to detect the presence of a flame. They work by analysing the light emitted by a flame and comparing it to a pre-determined set of parameters, such as the wavelength and intensity of the light. If a flame is detected, the detector will trigger an alarm or activate other building systems, such as sprinklers.

Flame detectors come in several different types, including ultraviolet (UV), infrared (IR) and visible light flame detectors. UV detectors are sensitive to the ultraviolet radiation emitted by most flames, IR detectors are sensitive to the infrared radiation emitted by most flames and visible light detectors are sensitive to the visible light emitted by most flames.

Flame detectors can be used in a variety of applications, including industrial plants, oil and gas facilities, power plants and commercial buildings. They are particularly useful in areas where traditional point smoke detectors may not be effective, such as in environments with high levels of dust, smoke or steam.

Flame detectors are generally considered to be highly reliable, but they can be affected by environmental factors such as sunlight and ambient lighting. They also require regular maintenance and calibration to ensure proper operation.