Lawrence Berkeley National Laboratory, or Berkeley Lab, researchers have identified indoor air filtration strategies to mitigate the spread of airborne infectious diseases in hopes of reducing superspreading events and outbreaks in collective public spaces.
The researchers used computer simulations to analyze various interior engineering systems such as ventilation, exhaustion, filtration and disinfection, according to a campus press release. Research has identified the need to invest in and implement building controls in real environments to further investigate factors such as comfort, operational challenges and energy costs.
The research focused on “simple” cases of buildings that used heating, ventilation and air conditioning, or HVAC, ventilation and filtration as primary engineering controls, according to Jacob Bueno de Mesquita, postdoctoral researcher at the within the Berkeley Lab’s Indoor Group.
“Many have talked about the idea of layered airborne viral protections, as well as the hierarchy of controls,” Bueno de Mesquita said in an email. “That means it happens ‘behind the scenes’ and makes the building’s interior spaces safer for human interaction.”
Bueno de Mesquita also noted that air purification is highly relevant in multiple settings, such as classrooms, gyms, and dorms, especially since these are “high-risk environments.” “where the spread is most likely to occur.
As for on-campus classrooms, HVAC systems have been implemented where “feasible” and building filters have been upgraded to “highest efficiency,” according to Patrick Kaulback, deputy principal. from the Office of Environment, Health and Safety..
Sally McGarrahan, assistant vice-chancellor for facilities services, added that efforts have been made to maximize the ventilation of classrooms with outside air when possible. In most cases, if the instructor is concerned about problematic ventilation, they can report it, she noted.
The campus took extra precautions following the COVID-19 pandemic and the return to in-person learning this semester, according to Kaulback.
Kaulback said in an email that California OSHA guidelines require the campus to “maximize ventilation and filtration” as much as possible.
Kaulback and the researchers added that controls such as ventilation and filtration are implemented along with other precautionary measures against infectious diseases such as COVID-19 or influenza, including vaccinations, face masks, outdoor gatherings and social distancing.
Bueno de Mesquita noted that these technical air purification solutions add up to a “bundle” of strategies that can be used individually or together.
“In general, water is treated before it reaches the tap and food is tested and inspected for safety, but there are no health standards for indoor air quality, despite a mode of transmission predominantly airborne for SARS-CoV-2, influenza, and other respiratory infections,” Mesquita said in the email. “If societies want to get to a place where they can avoid social lockdowns when new variants appear or other infectious diseases appear, or during annual flu epidemics, then air purification clearly supports this mission.”