How Sustainable are COVID-19 Mitigation Strategies for Buildings & People?
Over the summer of 2020, industry experts presented an overview of a specific COVID-19 mitigation topic, through a sustainability lens. The conversations with attendees that followed addressed issues like what building owners are asking for, which solutions are proving most effective, and how these strategies measure up against various sustainability imperatives. In addition to the priority of human health through reduced viral transmission, we discussed the long-term impacts on health (like ozone and UV exposure), the environment (like GHG emissions from increased energy use), and the economy (capital as well as operational cost).
Optimally, building industry professionals in practice look holistically at aspects of impact when making decisions. So to close the conversation series, we brought back all the industry experts for a panel discussion facilitated by Dr. Joseph G. Allen of the Harvard T.H. Chan School of Public Health. The panel broke down the latest and greatest (and not so great) methods of disease control through engineering, design, and building maintenance strategies and examined them by their effectiveness and considerations for building sustainability and human health. This website summarizes the information shared and serves as a resource for members of the green building industry who wish to become more informed about the current strategies,* while also balancing sustainability priorities.
*This information was last updated on August 20th, 2020 – we recognize that information about COVID-19 is rapidly changing and the information on these pages could be outdated. While this is a snapshot in time, this website may become a living document through community engagement in the comments section. If feasible, we will update the information so that this resource remains current.
Effectiveness x Environment Diagram
In the diagram above, we have compiled a working document that aims to identify, place, and compare a range of COVID-19 mitigation strategies while balancing the environmental impacts to both building costs and human health. Each strategy has a detailed explanation in its respective white papers, which can be found here. We believe that this diagram will continue to evolve over time as new research studies and data in the COVID-19 era unfold. Each project is unique and may, at times, require more than one of these strategies. If you have a solution or combination of solutions that you’ve implemented, drop it down in the comment box below.
Share Your Opinion!
We are currently collecting crowd-sourced feedback on the diagram you see above. If you have thoughts or opinions that you think would make the diagram more accurate, please complete the survey in the link below by Tuesday, August 25, 2020.
Evidence Airborne Transmission
Case studies like the Diamond Princess Cruise Ship, churches, combined with aerosol physics like particle size and rapid evaporation have suggested heavily that COVID-19 is an airborne transmissible virus. Recent air sampling studies have found samples of SARS-CoV-2 (the virus that causes COVID-19) in places where only air can reach. Nearly all outbreaks have been linked to time spent indoors within groups of three or more people. Epidemiologists have also found that most people don’t transfer to others, rather, super spreaders account for ten percent of the population and eighty percent of cases. Investing more research and funding into healthy buildings will hopefully take place in the near future, according to Dr. Joseph Allen’s brief interaction with Dr. Fauci.
Engineering controls in spaces falls to a mid-level hierarchy of actionable control effectiveness and business impact (see Figure 1). Ventilation in the 1900s had been set to avoid infectious disease transmission. Today, ventilation is commonly set for energy and cost-efficiency, much lower than the 1900s. When considering indoor environmental quality, questioning how much fresh air is appropriate for energy use and human health is imperative in the next steps toward evolving building codes and standards. We know what the sweet-spot is for energy efficiency and we know that increasing fresh air helps both dilute airborne viral particles and cognitive responsiveness. The next leap is toward testing them in combination with one another. (see the white paper on Fresh Air for more information and resources)
Beyond COVID-19 : Resiliency
Beyond the current pandemic, buildings impact global-scale systems such as climate change, water sources, and air pollution over time. It is our responsibility to design and build for resiliency and sustainability (see Figure 2). You can read more about this concept in the additional resources section at the bottom of this summary under “The Nexus of Green Building”.
Joseph Allen, DSC, MPH, CIH
Director of the Healthy Buildings Program
Featured Guest Speaker
John Swift | Air Filtration
Principal @ Buro Happold Engineering
Patrick Murphy | Fresh Air
Director of Sustainable Design @ Vanderweil Engineers
Nora McCawley | Humidity Control
Mechanical Engineer @ Buro Happold
Betty Lui | Pressurization
Mechanical Engineer @ Jacobs
Eric Edman | UV Light
Sr. Associate @ BR+A Consulting Engineers
Kathleen Hetrick | Air Monitoring
Sr. Sustainability Engineer @ Buro Happold Engineers
Monica Nakielski | Antimicrobials
Director of Sustainability & Environmental Health @ BCBS of MA
Aerosol and surface stability of HCoV-19 (SARS-CoV-2) compared to SARS-CoV-1
ASHRAE Position Document on Infectious Aerosols
ASHRAE Position Document on Infectious Aerosols
ASHRAE Guidance for Building Operations During the COVID-19 Pandemic
Lists mitigation strategies including air filtration upgrades and supplements.
Church Attendance and COVID Cases (CDC)
Diamond Princess Cruise Ship Case Study
Harnessing the power of healthy buildings research to advance health for all
Hong Kong Restaurant Case Study
Aerosol transmission of SARS-CoV-2 : Evidence for probable aerosol transmission of SARS-CoV-2 in a poorly ventilated restaurant
Viable SARS-CoV-2 in the air of a hospital room with COVID-19 patients
Why COVID-19 Raises the Stakes for Healthy Buildings
COVID-19 pushing the envelope of healthy buildings, a bigger picture article.
The need for this research remains in the light of the potential for new and old pandemics, and for continued exploration of how building systems may play a role in mitigating transmission.
December 2, 2019
Figure 1: Using a hierarchy of controls as a response framework, companies can take a range of actions – weighing the effectiveness and financial impact of each – to combat COVID-19 in their buildings. (source: https://hbr.org/2020/04/what-makes-an-office-building-healthy)
Figure 2: Infographic that (Source: https://forhealth.org/Harvard.ForHealthDotOrg.GreenBuildingsGlobalHealthSDGs.2017.pdf)
As occupants use a space, the infectious particles suspended in the air settle onto the surrounding surfaces, like floors and furniture, in addition to high touch surfaces, minutes, or even hours after occupants leave the room. The main focus is on floors, work surfaces/countertops, and furniture in this conversation…
Antimicrobials are naturally-occurring and fabricated chemicals added to common products with the goal of killing microbes and slowing down the spread of infections. Antimicrobial products can be sectioned to two main categories: pesticides and drugs/antiseptics…
As workers return to buildings after COVID-19, it is important to understand air quality to ensure mitigation strategies are effective. However, specific COVID-19 detectors are not yet available. Scientists and engineers are working on possible sensors and establishing reliable proxies for the virus…
Introducing UV-C lights into buildings during the COVID era can help to mitigate spread and create a safer environment. There are three main light placements: air stream disinfection, upper-air and room disinfection, and HVAC coil & surface cleaning. All types work to clean the air and ensure virus particles are killed…
Controlling “dirty” air movement that contains particulate matter (PM) through pressurization can help contain aerosolized droplet PM contaminated with COVID-19. The length of time a large group of people spends in one space as well as the direction of the airflow can all affect the spread of airborne diseases. Pressurization then is one measure used to control a building’s air flows…
Emerging research indicates that increasing the relative humidity in a space to 40% RH to 60% RH can help reduce the spread of coronaviruses. While this could be done at a whole-building level in critical spaces like hospitals and laboratories, humidification is energy intensive, and might be more economically implemented in small, dedicated areas…
Epidemiologists, the ASHRAE Epidemic Task Force, The U.S. Centers for Disease Control, and numerous other authorities on the COVID-19 Pandemic and respiratory disease generally have advised that outdoor air can reduce the risk of transmission. There’s increased importance in adequately ventilating spaces and even moving activities outdoors in response to the COVID-19 Pandemic…
When reopening buildings within the context of the current global pandemic, there are a number of HVAC system variables to consider for improving air quality. Designing for a specific level of air filtration, in combination with other best practices, will support a healthier environment. Different filters show varying levels of efficiency and necessity…
These papers were written and designed by Built Environment Plus interns, Catrina Schick and Kaleigh Stirrat, and edited by Built Environment Plus staff and the Conversation Series expert panel.