Dr. Jonathan Spero, an expert on pandemic preparedness and CEO of InHouse Physicians, offers tips to businesses on how to ensure that returning employees are free from the COVID-19 virus.

Guidelines for implementing temperature-taking in the workplace derive from a strategy called PDR, for Prevention, Detection and Response. Employers have the option of hiring staff to conduct the temperature checks with no-contact infrared thermometers, or purchase thermographic scanners, which can scan more people without the need for dedicated staff to operate them.

Companies should be aware that scanners aren’t highly regulated by the U.S. Food and Drug Administration, and vary widely in accuracy. Still, one can be obtained for a relatively small investment, given the savings from not having to devote individuals to their operation.

Just doing temperature checks isn’t enough to ensure health and safety in the workplace. Employers must have a policy for reacting to instances where an employee tests positive for the virus. And there’s always the possibility that a carrier of the disease might be asymptomatic.

There are no set standards for setting up testing regimens in the workplace. Some might choose to test all employees on a one-time basis as they arrive at work. Others might institute a regime of periodic testing. When it comes to determining the best method for testing and response, “It’s kind of the wild, wild West,” says Spero.

PDR is also a good model to follow when designing the workplace to minimize the risk of infections. “It’s all about health security,” says Spero. “A proven methodology out of the global public-health playbook.” Steps to take include ensuring social distancing, by rearranging work spaces, possibly with Plexiglas barriers. Masks are likely to be mandatory for employees returning to work in the near future.