This technology calibrates the thermal image with a blackbody calibration source in real-time to provide a system accuracy of better than 0.5°C and can, therefore, detect even small temperature changes induced by a fever. As a result, the vIRalert 2 system provides accurate and reliable skin temperature measurement for screening at point-of-entry into key facilities, like offices, factories, warehouses, schools, government buildings and any other places where infectious diseases can easily spread.