Many “fever screening systems” and “fever scanner system” on the market are nothing more than modified/rebadged/repackaged industrial thermal cameras. One of the standard functions on such industrial systems are ‘hot spot tracking’ and is conveniently activated as standard option. They will track the hottest spot on the screen (not necessarily human). However, there are no scientific relevance to this feature. In fact, when referred to clinical trials, research papers and real life experiences, these readings are highly misleading. All our systems, including the latest Sentry MK4 do not display subject’s core body temperature. We do however have an input which an operator can setup minimum screening threshold by indicating targeted core body temperature (e.g. mild fever @37.6degC to high fever at 38degC). Our systems will then automatically perform necessary system offsets and calibration to target individuals in that temperature group.