Blog Details

  • Home
  • Global Reflections & Large-Area Temperature Scanners Often Unreliable

Global Reflections & Large-Area Temperature Scanners Often Unreliable

Key Points:

Recommendations for Industry

Global Reflections

While the vaccines began to bring a surge of optimism about a winding down of the pandemic, recent increases in cases both around the globe and even in some states of the U.S. are causing us to rethink some of that positive vibe. The data is very concerning. With parts of Europe, Asia, Latin America, the Middle East, India all seeing resurgences in case numbers, and challenges with vaccine distribution, it just does not seem to be realistic to be thinking about it going away any time soon. This appears to be a combination of the spread of variants and the lack of parity in vaccine availability between countries, the pausing of the AstraZeneca vaccine due to reports of severe effects, and the overall hesitancy of people to be vaccinated.

So, once again, TAG continues to urge all businesses to continue to protect their workers, and the public, to the greatest extent possible. Continue full wellness checks, masking, distancing, handwashing, surface disinfection; continue to communicate the importance of these protections to your worker; and educate and encourage vaccinations as soon as eligible in your state.

Large-Area Temperature Scanners Often Unreliable

Wellness checks that including fever screening have been an essential part of COVID-19 protections since early in the pandemic. However, some methods of temperature taking are proving to be unreliable, particularly large-area thermal scanners (infrared thermographs/IRTs) – devices installed at the entrances of buildings to detect elevated temperatures as people walked through.

According to a research report by Conor Healy, etal., the studied scanners “generated human temperature measurements that were systematically biased to the mean human temperature.” As Healy discussed in an NPR interview (audio), “The fever cameras are taking a reading of a person’s surface temperature each time you get scanned, but they’re adjusting that reading before it gets shown to the user who is evaluating whether or not that person should enter a facility.” That compensating algorithm creates an appearance of normal function, so if they’re poorly manufactured or not used correctly, “the compensating algorithm might make up for that and make everything seem like it’s working just fine.”

One of the issues is that, while the scanners are considered medical devices, FDA waived the regulatory review requirements to help expand the availability of the systems during COVID. More recently, on March 1, FDA published an alert that “improper use of the systems may provide inaccurate temperature readings due to a variety of factors” and issued Warning Letters to several firms for offering unauthorized devices.

There are systems that do not use compensating algorithms which work when used correctly. But there also are a lot of extenuating circumstances that need to be considered, such as screening area humidity levels, ambient temperature, and light sources – as well as the impact of the person coming in from the extreme cold or heat. Additionally because fever is just one non-universal symptom of COVID-19, the devices would not catch those who are asymptomatic or without fever.

While these technologies can assist in detecting illness, TAG has recommended a comprehensive symptom-screening program since the start of the pandemic as the most reliable way to screen potentially infected employees. As case rates are on the rise in parts of the country, these programs remain an important line of defense against workplace transmission.

In Case You Missed It

Leave Comment