By Linda Childers
Businesses across the country are now reopening after the COVID-19 lockdown, with many implementing thermal imaging technology to help curb the spread of the disease.
But security experts tell Digital Privacy News that these thermal cameras offer limited accuracy and raise critical privacy concerns.
“Thermal cameras are still a form of surveillance,” said Matthew Guariglia, a policy analyst with the Electronic Frontier Foundation (EFF) in San Francisco. “Using this type of technology can open the door to increased use of face-recognition systems at a time when cities and states are attempting to ban it.”
Texas became one of the first states to begin reopening businesses in April.
Brian Greely, owner of Texas Surveillance and Security Systems in Houston, said his firm had supplied thermal imaging cameras to several area businesses as a frontline tool.
Using infrared imaging, these cameras can scan up to 5,000 people per hour.
“The cameras scan the body temperatures of 10 to 20 people at a time from a safe 20-foot distance, as they’re entering a facility,” Greely told Digital Privacy News. “This allows companies to keep lines moving, while also helping employees feel safer about going to work.”

“Thermal cameras are still a form of surveillance.”
Matthew Guariglia, Electronic Frontier Foundation.
CDC Directives
The thermal imaging cameras — in use at some airports, businesses and hospitals across the country — follow the Centers for Disease Control and Prevention’s (CDC) fever baseline of 100.4 or higher.
“The cameras focus on the inner corner of the tear duct around the eye to screen for an elevated body temperature,” Greely said. “If a person is wearing glasses or a helmet, the cameras focus on a vein on the forehead.”
If a fever is detected, the person is discreetly approached and told they are running a temperature, he explained. They then are asked to leave to protect others and are advised to see a doctor.
Privacy, Accuracy Issues
While many businesses are embracing the technology, others urge caution.
“We’ve already seen how surveillance cameras have made immigrants and vulnerable populations more reluctant to participate in activities or for people to visit their psychiatrist’s office if they’re being caught on camera — and the information has the potential to be shared with others,” EFF’s Guariglia told Digital Privacy News.
He added that thermal imaging might not be the most effective way to track COVID-19 cases.
“The cameras typically have an accuracy of (plus or minus) 2 degrees Fahrenheit,” he said. “Human temperatures tend to vary widely, as much as 2 degrees Fahrenheit, which could lead to a lot of false positives.”
Guariglia noted that people could be infected with coronavirus with no fever — or a low-grade one, particularly in the first few days.
“Some people who develop COVID-19 don’t develop symptoms, so thermal imaging cameras can offer a false sense of security,” he said, “and shouldn’t be the only safeguard that companies are using to protect against COVID-19.”

“In this case, the rewards outweigh risks to the consumer.”
Robert Siciliano, CEO, Protect Now.
Low Risk of Breaches
Since thermal imaging cameras are being used as a screening tool and aren’t storing data, Robert Siciliano, CEO of the Boston security consultancy Protect Now, said the risk of a security breach remained low.
In addition to thermal images making it hard to identify specific individuals, Siciliano said most companies delete the images at the end of the day.
“In this case, the rewards outweigh risks to the consumer,” Siciliano told Digital Privacy News.
“There’s always a chance that any personal data might be abused, which is why I advise consumers to always consider that their info may be shared with others — and making sure that information is useless to others.”
Regarding health information, Siciliano said patients should ask to see medical and insurance records to ensure they were accurate.
“By being proactive,” Siciliano said, “consumers can work to prevent purposeful or accidental exposure of private information.”
Linda Childers is a writer based in the San Francisco Bay Area.