Thermal Temperature Scanners: COVID-19 and Beyond
Soon to be as ubiquitous in the U.S. as they are in China and other parts of the world hit hard by the coronavirus pandemic, thermal or infrared cameras at entry points to buildings and facilities serve a valuable screening purpose in helping to slow down transmission of COVID-19 and other viruses. These devices also have significant limitations in functionality and reliability depending on the quality and sophistication of the equipment.
Lilker Technology Solutions Group Director, John Hassett, takes a look at how thermal cameras work, what the data tells you, and where the technology is headed.
The Science of Infrared
All objects—including human bodies—emit electromagnetic radiation, or simply put, light. The specific wavelengths emitted depend on the temperature of the object. Most of this light resides outside the visible spectrum, imperceptible to the human eye. Infrared technology serves as a bridge to the invisible, capturing a thermal image of the emitted light that corresponds to temperature. If someone has a fever (100.4 or higher, according to the CDC), their infrared scan should look different from someone without a fever.
Sounds good in theory, but there are caveats. An infrared camera measures skin temperature, which is generally cooler than body temperature and can change based on external conditions. Depending on the quality and resolution of the camera and software that adjusts for the differential, a more or less accurate reading can be obtained. Cameras that measure certain areas of the face, such as the tear ducts, render a more accurate reading.
Interpreting the Data
The presence of an elevated temperature is not an indicator of COVID-19; rather it raises a red flag that a person should be evaluated more closely before being allowed to enter a property. Although most cases present with fever, you can have a coronavirus without an elevated temperature. Conversely, you can have an elevated temperature due to some other virus or health condition, unrelated to COVID.
Because the data is only a first step in the screening process, an organization will need to have a protocol for dealing with persons who register a fever upon entering a building.
Equipment for Expediency
There are many different brands and types of infrared cameras of varying quality and cost flooding the market since the emergence of the novel coronavirus. The least expensive and most readily available is a standalone wall-mounted camera—a plug and play piece of equipment—and integrated software. If you are planning to purchase a thermal scanner, do your homework on the options to ensure the information you get from it will be reliable. Look for a high quality camera that takes multiple points of interest on the face. Remember that subjects need to actually look into or at the camera to be evaluated. Thermal cameras do not work well in crowds or with swiftly moving foot traffic.
Integrating Infrared into a Security System
While there is a current rush for building owners to get infrared camera add-ons so that we can all get back to work and play, the real benefits of infrared scanners may lie in the combination of high-end thermal cameras with facial recognition software and artificial intelligence (AI) in an integrated security building-wide system. This would allow building owners to monitor the temperature of occupants as well as to register those not wearing masks, compare the data with the facial recognition database and actually identify people in crowds to track movement and even pinpoint virus hotspots.
If you’d like more information on thermal cameras or to discuss your particular security system needs, please email John Hassett or call 212-695-1000.