The most common question from Facility Owners and Managers is how to control the perceived risk from COVID-19 associated with their properties in the event that a person with assumed COVID-19 case enters their facility. According to the Occupational Safety and Health Administration (OSHA), most American workers will likely experience low or medium exposure risk levels at their job or place of employment.
Owners and Managers are thinking about:
- trying to control a virus that spreads quickly through person-to-person contact
- preventing stigma and discrimination in the workplace
- reducing COVID-19 transmission among employees
- maintaining healthy business operations
- maintaining a safe and healthy work environment
According to the Centers for Disease Control and Prevention (CDC), the virus is believed to be transmitted through respiratory droplets produced when an infected person coughs or sneezes. These droplets can land in the mouths or noses of people who are nearby. The virus can also be spread by touching a surface or object that has the virus on it and then touching their own mouth, nose, or possibly eyes.
In order to control the risk of COVID-19, the CDC recommends that owners and managers cleaning and disinfecting surfaces that are touched daily (i.e., tables, doorknobs, light switches, countertops, handles, desks, phones, keyboards, desktop mouse, toilets, faucets, and sinks). If surfaces are dirty, they should be cleaned using a detergent or soap and water prior to disinfection. Most common EPA-registered household disinfectants should be effective.
How can facility managers know if cleaning efforts are working?
Contaminated surfaces play an important role in the transmission of microorganisms and potential viruses. As a result, methods for evaluating the cleanliness of work surfaces is becoming increasingly important, especially after employees return to work after a statewide shut-down due to a pandemic. Every microorganism and/or virus gives off adenosine triphosphate (ATP), which can be measured or quantified. Once a surface is cleaned, the current method is to visually inspection the cleaned surface. However, Essel can conduct validation testing to assess the effectiveness of the cleaning efforts.
Using a handheld meter (i.e., luminometer), Essel can quantify the amount of ATP bioluminescence present in a sample. The ATP luminometer measures the amount of light generated and provides information on the level of contaminate. The luminometer results are produced in seconds. The amount of contaminate is reported by the luminometer as Relative Light Units (RLU). The higher the RLU reading, the more contamination present.
How do you define clean? The CDC defines cleaning as the removal of germs, dirt, and impurities from surfaces. Cleaning does not kill germs, but by removing them, it lowers their numbers and the risk of spreading infection. Even though there are no published EPA or Occupational Health and Safety Administration (OSHA) RLU guidance values, recommendation for standard Pass/Fail RLU levels when using ATP luminometer have been provided as a benchmark. Based on the review of current published literature, the current recommended RLU benchmark values are suggested.
- Pass: <500 RLU
- Caution: 501–999 RLU
- Fail: >1000 RLU
However, Essel suggests that a value of 250 RLU pass value be used, consistent with hospital settings.
What if it is not possible to meet the recommended benchmark Pass/Fail values? It is important to understand that there are many variations in surfaces and cleaning practices. For example:
- The age and condition of the surface being tested; a new smooth surface will result in a lower RLU value than a surface that is older, scratched, and pitted.
- The nature of the surface being tested; a stainless steel surface is easier to clean when compared to wooden surface. The stainless steel surface should result in lower RLU values when compared to a wooden surface.
- The method of cleaning used; the kind of solvents and materials used will influence the adequacy of the cleaning; using water and a reused sponge will results in higher RLU values when compared to using a manufactured solvent and single use towels.
Benchmark Pass/Fail values may not be achievable under all circumstances and applying one set of Pass/Fail RLU values for all end users is not recommended because an acceptable RLU value for “Pass” depends on a number of factors, as described above. Essel can assist facility managers in determining site specific RLU values to monitor day to day cleaning performance, assess new cleaning protocols, and drive continuous improvement efforts on cleaning effectiveness.