The FDA has issued an alert about thermal-imaging systems intended to measure human body temperature because improper use of the systems may provide inaccurate temperature readings.

Also known as telethermographic systems, infrared thermographs, thermal cameras and “fever cameras,” the devices are currently being used for initial temperature checks and to triage individuals with elevated temperatures in public areas, such as airports, as part of COVID-19 risk management measures.

These systems have not been shown to be accurate when used to take the temperature of multiple individuals at the same time and should not be used for mass temperature screening, the FDA said.