When news on COVID-19 transmission within the Wuhan Province emerged in January, EI immediately responded with a series of blogs focused on occupational health and industrial hygiene practices which can minimize viral transmission in the workplace. Our blog series addressed the importance of including COVID-19 into corporate contingency plans, proper personal protective equipment, with special emphasis on the N95 respirator, using ambient CO2 levels as an indicator of indoor air quality and the importance of introducing outside air into buildings to reduce the concentration of indoor airborne contaminants, including COVID-19. Preventative measures are the first steps to take when facing a pandemic, but what happens when your workplace is exposed to a COVID-19 carrier? EI’s fifth blog focuses on cleaning and disinfection guidelines for handling potentially contaminated surfaces, as well as guidance on testing cleaning/disinfection efficiency.

COVID-19 – A Resilient Threat
At present, COVID-19 is transmitted from person-to-person primarily via virus-impacted droplets that are generated when infected persons cough, sneeze or speak. Studies have found that the COVID-19 virus can remain viable on surfaces for several hours up to days, including up to 24 hours on cardboard and up to three days on plastic and stainless steel.[1] Recent studies have also shown the resilience of the COVID-19 virus with its presence identified on a variety of surfaces in cruise ship cabins of both symptomatic and asymptomatic infected passengers up to 17 days after cabins were vacated, but before disinfection procedures had been conducted.[2] SARS, a genetically similar virus to COVID-19, is viable on surfaces such as glass, paper, plastic or wood for up to nine days.[3]

Cleaning/Disinfection Techniques
As the number of COVID-19 cases continues to expand, appropriate cleaning and disinfection procedures are critical in reducing the risk of viral transmission. Cleaning/disinfection guidelines and follow-up surface sampling procedures in the work environment should be based on current CDC recommendations.  Following cleaning/disinfection, adenosine triphosphate (ATP) sampling can be performed to document the cleaning/disinfection efficiency. While this method does not detect the specific type of pathogen left on the surface and cannot be used to detect the presence of viruses, ATP sampling measures residual organic matter on surfaces which provides an understanding of general surface cleanliness.

Cleaning and/or disinfection should be performed by personnel trained in basic infection control, including the proper use of effective hand hygiene techniques and the proper selection, donning and removal of personal protective equipment (PPE). All potentially contaminated surfaces and hard surface floors in potentially contaminated areas should be addressed using an EPA-registered disinfectant or diluted household bleach and water solution. These products should be used in accordance with manufacturer recommendations. Following disinfection efforts, a visual assessment and environmental sampling could be conducted to confirm surface cleanliness. 

How Can We Help?
The EI Group, Inc. (EI) is prepared to provide guidance on proper cleaning/disinfection measures, follow-up surface sampling services, proper PPE selection, as well as advise on the development of business contingency measures regarding COVID-19. Learn more about our capabilities at www.ei1.com. If you have questions or concerns regarding COVID-19 cleaning and disinfection, please contact Larry Rockefeller, CIH, CSP, Director of Industrial Hygiene Services, at (919) 730-5809 or lrockefeller@ei1.com.