Thermal imaging technology finds its roots in the night combat missions of the 1950 Korean War. Things have changed a lot since then and so has the technology. A thermographic camera has the unique ability to see what human beings can’t - the infrared light or heat. This makes it immensely useful for a number of applications, though its primary use has been restricted to the security and military domains.
There has always been a strong use-case for using thermal imaging in other applications – archaeology, medical, structural engineering, utilities (finding leaks in water/gas pipelines and power grids), agriculture, remote sensing, etc. However, the recent global pandemic engulfing the world has made a strong point for mass adoption of thermal screening.
Thermal imaging cameras need to be tuned to suit specific applications. Still, the basic principle remains the same and, in this article, our primary focus will be on screening people for temperature.
How is Human Thermal Body Imaging helpful?
The world has seen a number of outbreaks in the past couple of decades – SARS, MERS, Zika, Ebola, H1N1 Swine Flu, and the latest addition to the list – COVID-19. It seems inevitable that we will emerge victorious from the current pandemic of COVID-19, as we did from all other diseases in the past. But you never know where the next outbreak is coming from. As we have seen in the present coronavirus outbreak, timely screening and prevention will go a long way in limiting the spread of the virus.
Handheld thermal screening devices have suddenly become mainstream. Many government and commercial establishments have made it mandatory to screen visitors for temperature. Even though it does not offer fool-proof solution (asymptomatic patients can still find their way in), but it is a definite deterrent and a quite useful item to have in your toolbox.
A Strong Case for Thermal Screening of Crowds
Portable devices are good for places where there is limited footfall and the entry/exit points are easy to monitor, such as minor retail environments. When there is a need to monitor large scale gatherings at places such as factories, ports, warehousing, railways stations, airports and large shopping complexes and large manufacturing bases, individual screening is impractical.
This is where CCTV cameras with built-in thermal screening come in handy. This technology has already emerged as a frontline tool for battling the coronavirus. Thermal Imaging Cameras (TICs) will play a huge part when the world finally emerges from the present lockdown and they will continue to be helpful well beyond the reopening of the global economy.
How do Thermal Imaging Cameras Work?
Unlike handheld devices, TICs can monitor the temperature of a large number of people 30 to 50 in an instant, without the need to stop any of them. TICs are trained to focus on detecting faces of people and reading their temperatures. This reading is displayed in the CCTV feed together with the video, making it very easy to single out people with high temperature. Advanced TICs can even be programmed to display only the temperature reading that are beyond the normal range and be configured to send notifications i.e sms or emails, with still images attached or interact with other devices like door entry systems / access control or even time management devices.
Covid and Thermal Body Temperature Cameras, why?
- Mass screening – Large numbers of people can be screened instantly rather than them having to pass through screening booths one by one. This saves time and effort without compromising on efficiency, leading to a faster ROI.
- Parallel screening – People no longer need to be stopped in order to be screened. CCTV cameras can detect them coming from a distance and monitor their temperature for points of elevation. This is a huge time saver compared to the prevalent manual solution where each person must queue up and get screened.
- Multi-purpose – The CCTV feeds can be used both for the regular security work as well as for thermal screening. If you already have a CCTV network in your premises, the only major upgrade is of the camera while the rest of your infrastructure would remain the same.
- Cost-effective – In recent years, there has been a marked improvement in technology and costs have come down significantly, making thermal imaging cameras affordable for commercial use. As it minimizes manual involvement and screening time is cut down to nearly zero.
- Non-Invasive – These cameras operate silently in the background most people do not even realise they are in operation other than the notices displayed in regard to their presence. Correct configuration will also minimize any false positives nothing touches or invades anyone’s privacy.
What are the drawbacks of TICs?
- Suited for preliminary screening – TICs are the first step in detecting people with high temperature and it should not be taken as the final verdict. A secondary screening at a personal level is still required to get a more accurate temperature reading and confirm fever.
- False Positives – In order to ensure it detects cases with the slightest bit of fever, temperature threshold is often set lower, leading to false positives. Given that even half a degree of error can be decisive, its false positive detection rate (and subsequent follow-up screening that was not required in the first place) can be a concern. The margins are tight however you have to consider the alternatives, what technology are they replacing, enhancing or complementing.
- Not a one stop solution – As mentioned earlier, one cannot rely entirely on the results of TICs to make decisions about someone’s health. In cases like COVID-19, there are many patients who do not show any symptom but still act as carriers of the virus. Therefore, TIC is just an additional tool to help speed up screening process, but it is not a comprehensive solution in itself when it comes to identifying infected people in a group.
- Standards of Error – When installed incorrectly the margin of error is increased. Experienced installers can reduce and align with manufactures specifications in terms of tights possible margin of error.
- Shiny Shoes – Salesmen do not always fully understand the technology and use mixed terminology to get the sale. These cameras are here to help protect as well as ease concerns to diseases that are not fully understood, they have benefit and drawback. Dee.ie doesn’t believe in the shinny shoe salesman approach in all forms of technology never mind technology that is highly dependent on everyone safety and health.
Are they the right solution for your business?
That depends on what you do however if you have mass movement of people, then it's pretty much the only frontline defence. However, it is only one aspect and more use cases need to be explored.
It is worth mentioning that these aren’t cheap when compared to more common CCTV cameras. In fact, the cost can be six times as much. In addition, costs of correct installation, commissioning and support can be increased comparative to standard CCTV camera installation
That being said, do not think of TICs only as a defence mechanism for COVID-19. Can anyone envision a world where we are not going to be interested in other people running elevated temperatures around us? Does it seem that knowing your employee or site visitors are running a temperature the moment they enter your premises would be handy information to know?
Surely, it would be better if you already have a procedure in place for people reporting sick for duty? You can factor that in at the beginning of the day and make alternate arrangements for maintaining your productivity levels. Workplace health is still one of the leading issues for loss of productivity and detecting sick employees early will be a win-win situation for both.