Thermal scanning is a process of detection using thermography. It is used to detect radiation emitted by an object which increases with temperature. Thermal scanners are being used at airports and sea ports to screen passengers entering India and other countries. In this article, we will discuss the overview of thermal scanning, accuracy of thermal scanners, impact of air temperature on results and effectiveness of thermal screening at airports.
Thermal Scanning Overview
Thermography or thermal imaging refers to the use of infrared cameras to detect elevated body temperatures in humans. The thermal scanner measures the amount of infrared energy (heat) radiated from a person’s body surface. A trained professional operates the device and it should be held at 1 to 3 cm distance for accurate readings. The device then calculates the average temperature of the scanned area and displays that value as the temperature reading.
Accuracy of Thermal Scanners
The accuracy of thermal scanners depends upon the quality of the camera and its calibration. Generally, the best quality thermal scanners have an accuracy of 0.5°C. However, the accuracy may vary depending on the ambient air temperature and humidity levels.
Impact of Air Temperature on Results
Air temperature can affect the accuracy of the thermal scanner readings. If the air temperature is warmer than the subject's skin temperature, the scanner will record a higher temperature than what is actually present. Similarly, if the air temperature is cooler than the subject's skin temperature, the scanner will record a lower temperature than what is actually present. This means that the accuracy of the readings can be affected when the device is not positioned accurately.
Effectiveness of Thermal Screening at Airports
Thermal screening has been implemented at many airports around the world. According to preliminary estimates from the London School of Hygiene & Tropical Medicine (LSHTM), thermal screening at airports only detects less than 1 in 5 passengers arriving from a 12 hour flight who are infected with the new coronavirus. LAX has recently introduced a pilot program by installing thermal screening cameras designed to detect fevers in the facility. These cameras are designed to detect body temperatures of 100.4 degrees or more, the current standard definition for a fever established by the Centers for Disease Control.
Conclusion
In conclusion, thermal scanning is a useful tool for detecting elevated body temperatures, but its accuracy is dependent on the quality of the camera, its calibration and the ambient air temperature. Although thermal scanning can be effective in detecting individuals with a fever, it cannot provide 100% accuracy. Therefore, additional measures such as contact tracing and quarantine must be taken to ensure public safety.
Leave a Reply