There are many companies jumping into selling temperature detection systems to the state, local governments, hospitals, airports and local businesses, but do they know how to drive one? Anyone can get behind a car and drive it into a wall by accident. The same can happen with a temperature detection system.
The first thing you should ask is “does my firm have a certified thermographer?”. If not, the firm are at risk of getting a low quality system that is being resold to make quick cash. Businesses that are doing this do not know how to operate it properly.
Asking the right questions
Secondly, you should ask whether the system is NDAA compliant. NDAA compliance means that your temperature detection equipment is protected by U.S. law.
Does your system have a HSRP device (blackbody)? HSRP (Heat Source Reference Point) is a device that will allow the camera to detect the correct temperature a distance. Even if the room temperature does change throughout the day, treat it as a reference point for the camera to know the temperature at that distance.
Can your system scan mutliple people at once?
Can your system scan mutliple people at once? This is a bad question but often asked since most systems will say yes. For ease, everyone wants to scan many people at once, but the best practice according to FDA and CDC guidelines is to run one person at a time for best accuracy. Why? The HSRP (blackbody) device tells the camera what the correct temperature is at a given distance away from the camera. Every foot you are away from the HSRP device will be off by 0.1 degrees roughly. If you are in a room full of people, let's say 6, in view of the camera, every person that is not next to the HSRP device (5) will be given an inaccurate reading. Hence why it is so important to run the system correctly with just one person at a time. You will also need to follow the 6 feet rule. If you take that into consideration, one at a time at 6 feet apart, the device should tell you how you need to run the system.
Sensitivity of thermal imaging
Is your system’s sensor accurate enough? The FDA recommends an error of ±0.5°C or better. When looking for a system, make sure it is better than what they recommend. I would recommend ±0.3°C or better. Do not purchase a system over ±-.5°C degrees as you are doing yourself and your customers or employees an injustice. Another thing to look at is how many pixels it can determine the temperature from. Some cameras can only tell the temperature of 6 points on the screen, whilst others can take a temperature reading from each pixel. Take a 384x288 camera, for example, which would be over 110,000 points of temperature taking on a single image.
Thermal cameras are very sensitive, so there are a lot of do’s and don’ts. For example, the system cannot see through glasses or hats.
On the below image you can see a person with the visual camera on the right, whilst on the left side is through a thermal camera. Both are pointing at the same area. It is clear the person on the left side is “invisible” to the thermal imaging camera.
| Demonstrating the sensitivity of thermal imaging |
If you are a company who wants to detect the temperature of customers or employees though the front door, window or a car window, the answer would be no. You need a clear line of sight without any interference to scan for temperatures. Other things you need to look out for is wind and distance away from the HSRP (blackbody) device. Air and distance away from the HSRP device will make the system less and less accurate the more space between the device.
Air and distance away from the HSRP device will make the system less and less accurate
Thermal imaging and COVID-19
If you have a clear line of sight, is there anything I need to know? The answer is yes. Reflective materials such as metal can interfere with your temperature readings. Reflective materials are easily picked up from the thermal side so pointing at a medal, glass or anything reflective can cause inaccuracies within the system.
In the age of COVID-19, temperature detection systems are more important than ever. Organisations must get a system in place to help scan for high temperatures in order to reduce the spread of the virus.