​Can we use infrared Camera to measure body temperature and detect fever/Covid-19?

​Can we use infrared Camera to measure body temperature and detect fever/Covid-19?

Can we use infrared Camera to measure body temperature and detect fever/Covid-19?

The world is currently struggling with a pandemic caused by the coronavirus disease, coronavirus disease (COVID-19) is an infectious disease caused by a newly discovered coronavirus.

Common signs of the presence of this disease include respiratory symptoms, fever, cough, shortness of breath, and breathing difficulties. In more severe cases, infection can cause pneumonia, severe acute respiratory syndrome,kidney failure and even death.Most people infected with the COVID-19 virus will recover without requiring special treatment. Older people, and those with underlying medical problems like cardiovascular disease, diabetes, chronic respiratory disease, and cancer are more likely todevelop serious illness.

Easiest form of early detection.

One of the best preliminary tests for presence of COVID-19 is by checking for fever, body temperature screening (fever) is the major test performed at points of entry, i.e airports, on the returning travelers in most of the countries with limited resources. This practice has limited results because recent research shows thatasymptomatic carriers of COVID-19are not detected using the temperature measurements. However, we are helpless but still we need to check for fever. and need to observe social distancing. WHO had recommended that people should avoid close contact (1 meter or 3 feet) with people who are unwell. Using the traditionalinfrared thermometerto check for people with high body temperature becomes inadequate, the infrared thermometer in the market is used with 5cm of the body to get an accurate temperature measurement of the body.

This article reviews why it is important to use an infrared camera which can take accurate temperature measurements from a further distance thereby following the world bank recommended social distances to mitigate spread of COVID-19.

The limitations of the infrared thermometer.

The most important features of an infrared thermometer are the accuracy of measurements and that is greatly determined by the distance of the camera from target to be measured. As the target size decreases,or the distance to the target increases, a larger D/S ratio becomes necessary. Using the same example and changing first the target size and then the D/S ratio, you see that this formula helps you decide the correct D/S ratio and, subsequently, the handheld IR thermometer for your needs.

  • D/S Ratio x Target Size or 8:1 x 2 = maximum measure distance of 16 inches
  • D/S Ratio x Target Size or 12:1 x 2 = maximum measure distance of 24 inches

D/S ratios vary greatly, so carefully compare this feature of handheld IR thermometers when shopping. The two biggest factors to consider when selecting an IR thermometer are the D/S ratio and temperature range.

This makes for a limitation of measuring distances for most products to only 5cm to 8cm. Regrettably, this is way below the WHO recommended social distance of 100 cm or 3 feet. The infrared camera becomes very important, but can it safely measure body temperature from a safe distance? Is infrared radiation safe for humans? We want to answer these questions in this article.

What are the other names of infrared cameras?

Infrared camera is also called a thermographic camera, or thermal imaging camera. These names will be used interchangeably in this article, they represent the same thing.

How does an infrared camera work?

The first step to understanding if there are really any health implications using infrared cameras to detect body temperature is understanding how it works. What is the science behind an infrared camera?

An infrared camera works exactly the same way infrared thermometer do, they both work based on an infrared energy detection.

An infrared camera is a non-contact device that detects infrared energy (heat) and converts it into an electronic signal, which is then processed to produce a thermal image on a video monitor and perform temperature calculations. Heat sensed by an infrared camera can be very precisely quantified, or measured, allowing you to not only monitor thermal performance, but also identify and evaluate the relative severity of heat-related problems. This is a result of recent innovations, particularly detector technology, the incorporation of built-in visual imaging, automatic functionality, and infrared software development, deliver more cost-effective thermal analysis solutions than ever before.Thermal imaging cameras contain a special lens which focuses the heat, or infrared energy which is given off by an object onto a detector which is sensitive to heat. So, being that it is unaffected by light, thermal imaging will work just as well in daylight as in complete darkness.

How far can the infrared camera go?

We understand the limitations of the infrared thermometer, the distance to get accurate measurement, does this apply when using the infrared camera? No! The infrared camera can get accurate temperature measurement from a safe distance. However, how far away you will be able to detect a person using a thermal imager is a function of the lens field of view (FOV), the number of pixels and the ambient temperature (or the difference between a person and the surrounding temperature). These are optimal conditions with a cool background and a warm human, so results will vary with environmental conditions.

The FLIR One will detect a person atabout 30m (or 100’)under good conditions, meaning you will see a hot spot. With the FLIR One PRO under the same conditions you will detect a person at about 40m (or 130’). More so the resolution of a thermal camerawill be an added advantage to the process of decision making.

Are infrared cameras safe for humans?

Infrared cameras are safe on humans. An infrared camera (or thermal camera) is a non-contact device that detects infrared energy (heat) and converts it into an electronic signal.

Thermal cameras let people see what their eyes can’t; invisible heat radiation emitted or reflected by all objects, regardless of lighting conditions. Some of the greatest benefits of thermal cameras are the domain of security. Security cameras have become a staple of protection for many (if not all) major businesses, hence the need to produce quality images is critical to provide constant protection against potential intruders. Truly thermal cameras offer superior protection in challenging conditions.

Other benefits of using infrared cameras are:

1.Low-Light Scenarios

2.Immune to Visual Limitations

3.Camouflaging Foliage

4.Fewer False Alarms

5.Higher Return on Investment

Infrared Camera Applications and Uses

Originally developed for military use during the Korean war, thermal imaging cameras have migrated into other fields and have found many uses. Firefighters use them to see through smoke, find people and localize hotspots of fires. Law enforcement uses the technology to manage surveillance activities, locate and apprehend suspects, investigate crime scenes and conduct search and rescue operations. Power line maintenance technicians locate overheating joints and parts to eliminate potential failures. Where thermal insulation becomes faulty, building construction technicians can see heat leaks to improve the efficiencies of cooling or heating. Physiological activities, such as fever, in human beings and other warm-blooded animals can also be monitored with thermographic imaging. They are also common tools used by home inspectors.

Infrared Camera Limitations

Thermal energy can be reflected off shiny surfaces, thermal imaging cameras cannot see through glass. Thermal imaging cameras can be used to gather information about the inside of a wall, but they cannot see through walls. It is also important to know that thermal imaging cameras should not be used as the only deciding factor that a problem exists. Using other instruments should always be used to confirm the problem.

Making the transition to thermal cameras.

In the spirit of observing the mandatory social distancing recommendation by the World health organization, it is expedient that organizations, individuals, public organizations, airports and areas with high volume of human traffic should install thermographic cameras. This will help to quickly and accurately detect persons with suspected electated temperatures or fever, it is safer, non-intrusive and accurate. If you need a mobile handheld thermal camera, we have softened decision making by comparing two great brands Bosch and Flir, make that bold transition and don't allow your front line staff to be in harm’s way. Your frontline staff should get body temperature from a safe distance, using the infrared camera, with optimum resolution and storage capabilities to be retrieved in the future.

What can I do to protect myself from COVID-19?

Temperature measurements to detect fever, and observing social distance are only some of the recommended standard practices by WHO. Other standard recommendations to reduce exposure to and transmission of a range of illnesses include maintaining basic hand and respiratory hygiene, and safe food practices, avoiding close contact when possible with anyone showing symptoms of respiratory illness such as coughing and sneezing. Please stay safe.

Kindly Contact Us for more information

Apr 24, 2020

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