Silent Talker Lie Detector a multi-factor model including cognitive load, duping delight and behaviour control, its inventors claim that it is robust to countermeasures. In fact it is believed that because a large number of channels are used, attempts at behaviour control will generate more incongruities between channels which can be detected. Further experimental trials are required to investigate this hypothesis. Challenges with this technological approach include: Silent Talker Lie Detector The Silent Talker Psychological Profiler is a camera system which observes and analyses non-verbal behaviour in the form of micro-gestures while a subject is being interviewed, for the claimed purpose of credibility assessment.
Flame detector detectors have an (automatic) detector window self test, but this self test only monitors the occurrence of water or ice on the detector window. A salt film is also harmful, because salt absorbs water. However, water vapour, fog or light rain also makes the sensor almost blind, without the user knowing. The cause is similar to what a fire fighter does if he approaches a hot fire: he protects himself by means of a water vapour screen against the enormous infrared heat radiation. The presence of water vapor, fog, or light rain will then also "protect" the monitor causing it