New concerns about usefulness and reliability of thermal imaging cameras

The cameras are used to check if someone has a fever, which is one symptom of COVID-19
Posted at 8:14 AM, Jun 14, 2020
and last updated 2020-06-14 10:14:26-04

SALT LAKE CITY — Typically when you have your temperature taken at the doctor, it's with a thermometer in your mouth or your ear, but now some businesses are using tech to check if you have a fever before entering, because it's one of the symptoms of COVID-19.

The problem is, the cameras being used may not be quite as accurate as we think they are if they're not used properly.

The room for error is raising concerns for experts like Rajesh Menon, an Electrical Engineering Professor at the University of Utah.

"Unfortunately, data from previous crises like SARS and Ebola, seem to indicate that the effectiveness of this approach really depends upon how well it’s executed, how well it’s set up, and how well the protocols are followed," said Menon.

He also says there are some complications that come with getting an accurate reading, like the temperature on the surface of your skin may not reflect the temperature of your body.

Menon said the most reliable place to measure temperature is actually the tear duct of the eye or inside your mouth.

Another area of concern is for people who are not showing any symptoms, whether it's because they are asymptomatic, or they took something to mask their symptoms.

"If one takes a fever-reducing medication, your fever goes away, so the camera does not detect it, so that’s another obvious practical reason [for not relying on the cameras alone]," said Menon.

The U of U professor also said people could raise privacy concerns about the use of thermal imaging cameras because customers may not have given their permission to record their images, even if they are just in infrared.

He thinks the cameras could be improved in terms of accuracy if they also used artificial intelligence (AI), which is something he researches with students at his lab.

Menon said, "All of these [cameras] should be treated essentially as a tool to give us peace of mind that allows us to have society come back to life."

The electrical engineering professor went on to says that we should really treat thermal imaging cameras like another tool in our arsenal, just as we do face masks, social distancing, and eventually a vaccine.

Examples of companies that offer thermal imaging cameras for businesses are D-Link and FLIR.

In a blog post on their website, FLIR wrote "If the temperature of the skin in key areas (especially the corner of the eye and forehead) is above average temperature, then the individual may be selected for additional screening. Identifying individuals with EBT (Elevated Body Temperature), who should then be further screened with virus-specific diagnostic tests, can help reduce or dramatically slow the spread of viruses and infections."

All of this isn't to say the thermal imaging cameras do not work, but it does mean we need to be careful about making sure that the equipment is calibrated properly, so it doesn't produce inaccurate results.