Air Quality is Key to Safely Returning to the Workplace
As companies and organizations consider how to best adjust workplace operations in spaces that were designed in a precoronavirus world, building owners and occupants should take a close look at a key factor that appears to have a significant impact on infection rates: indoor air quality. Enabling physical social distancing and eliminating common surface touch points are highly visible tactics that provide transparency to an organization’s efforts to minimize the risk of COVID-19 transmission. But what about the “invisible” risks of transmission that are worrying virologists and researchers – the effects of gathering and working within enclosed spaces for long periods of time?
We have the same concerns as our clients for determining best practices for ensuring a safe return to the workplace. Using the latest recommendations provided by the American Society of Heating and Refrigeration Engineers and the Centers for Disease Control, we instituted a program to research the impacts of changes to our heating, ventilation and air-conditioning systems on our own indoor air quality. Since our headquarters is only 20,000 square feet within a 256,000-sf building, we approached our landlord, The Chancery Sentinel LLC, a subsidiary of Zaser & Longston Inc., to see if we could make modifications to the building’s ventilation systems to improve indoor air quality. Our landlord embraced the opportunity, noting it was appreciative of the resource and level of concern coming from one of its tenants.
During the past decade, many building HVAC control systems have been adjusted to maximize energy conservation. Under certain conditions, the control systems minimize the amount of outside ventilation air to reduce energy usage. Municipal code requires all buildings to have a minimum level of ventilation that is adequate during normal times but these minimal ventilation levels can be woefully inadequate during a pandemic. Ventilation rates for occupied spaces should be maximized to the limits of the existing heating and cooling systems’ ability to support the temperature requirements of the space. The ability to maximize and/or increase the amount of ventilation air in a building can range from simple control changes to more difficult system modifications. For buildings already equipped with full economizer capabilities, modifications of the control systems can be performed that will maximize the amount of outside air that that is delivered to the occupied spaces and will in turn maximize the amount of exhaust from the building. There are additional modifications that should be made to ensure that the increased ventilation is maintained. This may include increasing the discharge air temperature during cooling mode so that the variable air volume and fan powered boxes continue to deliver a higher flow rate.
Working with The Chancery Sentinel, we looked at changes that could be implemented with minimal upfront costs, but that would have a significant positive impact on office environment. The engineers on our team identified four primary steps the building’s owner could take to improve the indoor air quality. These included:
• Adjusting the ventilation system controls so that the amount of outside air delivered to the space was increased from 25% to 50% of the total circulated air.
• Running the restroom exhaust fans 24 hours per day.
• Running the ventilation systems on 100% outside air prior to building occupancy to flush the building with fresh air.
• Upgrading the ventilation system air filtration from a filter efficiency rating of MERV 11 to MERV 13. Based on current information, MERV 13 filters entrap particles of the size of the airborne virus.
We recently supplemented these efforts with the installation of a Needle Point Bipolar Ionization system into the supply air ductwork serving our office space. This system was chosen because it has undergone initial independent testing that indicates it is 99.4% effective in killing the SARS-CoV-2 pathogen responsible for COVID-19, and is used in many health care facilities. Its primary purpose is to provide an additional level of protection from the potential of aerosol-based contaminants in the air stream. We are working with the manufacturer to test the effectiveness of the system in the office environment.
James Moilanen, vice president of real estate at Zaser & Longston, said the result was a win-win. “The costs of the adjustments themselves are minimal, and while we expect an increase in energy usage for the building overall, we want to take every positive step possible toward ensuring the safety for all tenants and visitors in our building,” he said.
We have taken a phased approach with managing our workload by successfully working remotely at the onset of the pandemic, implementing these air quality improvement efforts as we reintroduced the opportunity to return to the office. We are working at a reduced density of 40% capacity within the office and implemented health screening including temperature checks for anyone entering our office space, new cleaning protocols, hand sanitizers throughout the office, mandatory masks and social distancing within the office.
Teamwork and interaction is key to successful design and construction projects. While technology offers opportunities to collaborate and develop solutions remotely, the physical spaces we occupy and the human interaction within also contribute to workplace culture. Building owners and operators should be taking a close look at the HVAC and controls systems as an important component in their overall COVID-19 mitigation strategies.
Published in the September 2020 issue of Building Dialogue.