Coronavirus Concerns: Is it Safe to Go Back?

Mar 25, 2020

There is much we don’t know about the SARS-CoV-2 coronavirus that causes COVID-19. With much uncertainty, comes much fear. Eventually, Illinois’ Stay-at-Home Executive Order will end and nervous employees will be heading back to their places of employment. The fear will be amplified in those buildings where there was a confirmed case of COVID-19. I envision a group of employees huddled at the front door all saying, “You go in first!” and wondering, is it safe?

What can a business owner, property manager, or school administrator do to ensure that the space is ready for re-occupancy?


Most virologists say that the SARS-CoV-2 coronavirus cannot survive on inanimate surfaces for more than 9 days. Therefore, one way to reduce risk is to vacate the space for 9 days. Although this may be a good option for some, there are key limitations to waiting it out.

Many businesses and institutions are providing essential services and the option of keeping the space totally empty for 9 days is unrealistic. Another issue with waiting it out is that some employees may feel like the building management did not take this problem seriously. “Just waiting” doesn’t provide the comfort and action that employees are looking for. Employees like to see that precautionary measures were taken and their concerns were addressed.

Deep Clean and Disinfect

Another option is for buildings to do a deep clean and disinfection. Each building has its own normal cleaning procedures, but those are designed for regular cleaning, not decontaminating surfaces for an emerging pathogen. Deep cleaning and disinfection may be performed by the normal cleaning company or by outside specialty providers.

The term “deep cleaning” has no formal definition, but it indicates extra effort beyond routine practice. It is important to make a distinction between the terms cleaning, sanitizing, and disinfecting. Cleaning physically removes dust, dirt, and grime from a surface without killing anything. Sanitizing is meant to reduce, but not necessarily totally eliminate germs. Disinfecting is designed to kill all viable microorganisms present (but you need the next level up, a sterilizer, to kill any spores). In the case of a pathogenic agent like the coronavirus, a disinfectant is needed. But disinfectants typically require surfaces to be first cleaned before their application.

A good strategy is to clean high-touch surfaces and then apply a disinfectant for which the EPA has given provisional approval by including it in List N. It is important to use disinfectants according to the instructions on the label. If it calls for a 10-minute dwell time, then the surface needs to be wet with disinfectant for that long. It may require multiple applications to achieve the needed dwell time.

Verification Testing

For property managers and company owners that really want to document their due diligence, they should consider third-party verification testing. This involves having an industrial hygienist test high-touch surfaces to determine if they meet cleanliness standards. Although there are no commercially-available swabs and analytical methods to detect SARS-CoV-2 viruses on surfaces (now there are!), an industrial hygienist can test surfaces for biological cleanliness in general. These methods could detect the presence of bacteria, which would be released from a cough or sneeze along with coronavirus. Another surrogate method involves using an invisible fluorescent gel to mark surfaces prior to cleaning, and then checking with an ultraviolet light after cleaning was performed to see if the gel was removed in the cleaning procedures.


Although we don’t know when the Stay-At-Home Executive Order will end, we do know that when employees go back to work, they will be concerned about coronavirus being on light switches, door knobs, and elevator buttons. For those buildings that cannot just wait it out, the best option is to hire Indoor Science to develop a coronavirus cleaning protocol and perform 3rd party verification that a cleanliness standard was met. If someone down the road contracts COVID-19 in the building, you will have done your due diligence to document proper cleaning was achieved.