Organisations can then decide how best to deploy this information based on region, culture and the critical nature of the facility. In some circumstances a security officer may ask the person to scan their temperature using a medically approved sensor. In others, the person may be denied access to the facility. Ultimately, it is a decision for each organisation on how best to deploy the solution.
Thermal body temperature solutions
An important distinction to make in the overall societal response to COVID-19 is that body temperature solutions are not a medical solution. They cannot identify the virus and they do not protect organizations or individuals from catching the virus.
Thermal body temperature solutions are a tool that can support the identification of a key symptom of the disease. They can help organizations identify people showing these symptoms, but they do not diagnose or treat COVID-19. However, this does not mean that thermal body temperature solutions do not add value in the overall response. In fact, they provide a non-invasive method to check body temperature, can do this at faster rates than hand-held scanners and at a greater (potentially safer) distance. The deployment of these solutions in a facility may even encourage positive behaviour with staff more likely to stay at home when they are unwell with a fever.
Thermal body temperature solutions require, at a minimum, a radiometric thermal camera to measure temperature differences in people entering the field of view. More advanced solutions will use blackbody devices to help calibrate the temperature measurement, especially in less controlled environments where the elements can influence the reading. AI (Artificial Intelligence) algorithms can also be integrated to help target the temperature reading on the most accurate part of the body, typically the forehead or near the eyes.
The blackbody calibration tool consists of a target object whose temperature is precisely known and controlled. Specifically, this is important in human temperature measurement where accuracy to +/- 0.3 degrees Celsius is advised by many international standards organizations. By deploying the blackbody calibration tool, it is easier to establish an accurate relationship between gray level and temperature. Essentially there is known, fixed temperature object in the field of view which can be used to calibrate and measure all other objects’ temperatures. Using this method, false temperature alarms caused by environmental influence can be effectively reduced, and the accuracy of the thermal body temperature solution can be controlled to more precise parameters. However, monitoring accuracy does depend on the stability of the body temperature and it is recommended to install the system in a stable environmental condition to ensure that the skin temperature is stable.
The emergence of AI technology, and specifically face detection algorithms, will play an important role in the evolution of these solutions too. Algorithms can help complete more accurate temperature tests. Cameras can do this by locating specific areas of the face, such as the forehead or eyes, more accurately. This could be critical in the case of people wearing masks. Combining thermal cameras and facial detection can enable thermal body temperature solutions to combine accurate temperature scanning with the best face location to take the measurement from, improving the overall measurement accuracy.
It should also be noted that facial detection, as opposed to recognition, is used to improve the accuracy of the solution with better positioning of the measuring point on the face. It is not used to detect specific individuals and does not break privacy compliances (such as GDPR). While there remain challenges to the effectiveness of thermal imaging cameras for measuring human body temperature in public areas, especially when face masks are commonplace, the introduction of facial detection and AI can improve the accuracy of temperature scanning.