Amazon.com has started to use thermal cameras at its warehouses to speed up screening for feverish workers who could be infected with the coronavirus.

The cameras measure how much heat people emit relative to their surroundings, says a news report. They require less time and contact than forehead thermometers, earlier adopted by Amazon, the report says.

Amazon has set up the hardware for the thermal cameras in at least six warehouses outside Los Angeles and Seattle, where the company is based, according to the news report.

Thermal cameras will also replace thermometers at worker entrances to many of Amazon’s Whole Foods stores, it says.

The company performs a second, forehead thermometer check on anyone flagged by the cameras to determine an exact temperature, the report notes. An international standard requires the extra check, though one camera system maker said the infrared scan is more accurate than a thermometer.