By JEFFREY H. PETERS, P.E., LEED AP, BD+C, MAC, CEICC, and KIERAN PURCELL, P.E., LEED AP
There are high levels of fear and misinformation surrounding COVID-19. Building owners and property managers must address the need for spaces to be occupied while assuring occupants that due diligence has been performed concerning the mitigation and continued control of the virus. Some buildings were decommissioned quickly, and now that employees are slowly returning to the office, owners and managers need to ensure that buildings are running optimally.
Why test spaces?
To offer peace of mind to tenants as they return to their spaces, mitigation measures can be documented and confirmed through cleaning verification testing, which ensures that decontamination efforts have been performed correctly. Building owners and property managers may also be responsible for fulfilling contractual obligations regarding a decontamination response or plan of action. Historic data suggests there will be another peak of infection; mitigation and continued decontamination plans, along with cleaning verification, may become the norm for many public spaces.
Polymerase Chain Reaction (PCR) testing is a test that can be performed to identify the presence of SARS-CoV-2 genetic material on surfaces in order to determine if a workspace has been impacted by the virus. Samples are sent to a laboratory for analysis and results can be produced within 24 hours.
Adenosine Triphosphate (ATP) testing is recommended for post-decontamination cleaning verification testing. This technology is a real-time meter that provides a quantifiable measurement of microorganisms from a given sample. For this testing, a swab is moistened, swiped on a surface, and inserted into a meter for analysis. This equipment is a staple in the food and healthcare industries for rapid identification of the cleanliness of surfaces. ATP testing does not test directly for viruses; however, it tests indirectly by measuring organic material (ATP) that should have been removed along with viruses. ATP testing is a way to confirm overall effectiveness of the cleaning procedures / protocols.
SARS-CoV-2 viral particles can take several hours to settle on surfaces through the air and can be active on these surfaces for several days. The virus has a weak, vulnerable outer membrane and is susceptible to breakdown from both a chemical and physical standpoint. Washing hands with soap and water physically removes the virus from the surface of your hands as well as inactivates it.
U.S. EPA’s “List N” has approximately 400 chemicals approved for disinfectant use against SARS-CoV-2. The list provides the contact time of these disinfectant chemicals, which can break down the virus as long as they are allowed enough dwell time to be effective. Exercise caution with regards to where and how liquid chemicals are used, as some have been found to be corrosive to electronic equipment.
Decontamination of public spaces involves determining which surfaces to clean, including assessment of high-touch surfaces, as well as the scope of the entire cleaning process. Depending on the circumstance, this could require janitorial, maintenance, or third-party cleaning and restoration services.
We recommend beginning with physically removing matter from surfaces by wiping them down with soap, water, and disposable microfiber cloths using a single-wipe motion. Once surfaces have dried, disinfectants should be applied to high-touch surfaces. In unique circumstances, electrostatic misting/fogging and the use of ultraviolet (UV) lighting and ozonation of unoccupied spaces may also be utilized to offer additional reassurance regarding decontamination efforts.
Once occupant safety has been ensured via cleaning measures, the health of building systems should be evaluated. During shutdown, many building systems, including plumbing, air conditioning, electrical, elevators, alarms, fire protection, and more have been turned off or running at reduced use for long periods of time. We recommend evaluating these systems before bringing them back to full use.
Because warm, stagnant water can allow Legionella and other organisms to grow, plumbing systems need to be restarted and flushed. The water in the plumbing systems should flow long enough to confirm the disinfectant levels (chlorine, etc.) at the farthest outlets are equal to the incoming water supply.
Electrical systems may not need as much maintenance but should also be reviewed for updates, such as the addition of touchless controls to otherwise high-contact surfaces. For continuous disinfection, upper level air ultraviolet germicidal irradiation (UVGI) light fixtures may be considered.
Heating, ventilation, and air conditioning (HVAC) systems do not need special cleaning for viruses. However, issues may still arise due to prolonged system shutdown or idling. Systems should be purged with fresh air if stale or chemical odors have developed during shutdown. Thorough cleaning will be required if high humidity has caused mold growth. Filter maintenance is also encouraged; protective equipment should be worn during this process.
Elevator maintenance issues should be addressed and new socially distant procedures for elevator use may need to be established. This should include signage outside the cabs to limit the number of people entering and signage inside the cabs showing the best positions in which to stand to avoid facing each other.
New Building Normal
As employees begin transitioning back into the office, certain screening and safety procedures for re-entry of buildings by staff and guests should be established. This may include temperature screening processes; purchasing/providing hand sanitizer, face masks, or other protective equipment; defining physical distance guidelines; and installing directive signage.
Property managers and building owners need to be vigilant when reopening buildings to ensure that systems and operations are recommissioned properly. Take the time to create a plan and consult experts that can assist with the necessary codes and local jurisdictions.
A 30-year industry veteran, Peters is VP and national MEP division manager for Houston-based Rimkus Consulting Group. He investigates and develops repair and remediation plans for commercial, educational, institutional, residential, and green buildings involving mechanical, HVAC, electrical, plumbing, steam, building systems, and building envelopes.
Based in Austin TX, Purcell is an environmental engineer and director of the Rimkus Environmental Division, where he conducts facility compliance and permitting assessments, and develops remediation strategies for contaminated properties. .