Seattle, Washington — Proper ventilation has been identified by health experts as an important practice to minimize the spread of airborne viruses such as COVID-19.
School districts throughout the country are taking note. Particularly proactive in learning about and implementing effective ventilation solutions are schools in Washington State, reports the Seattle Times.
It’s no wonder, given the flood of questions the Seattle Times Education Lab has received over the past month about indoor air quality in schools and measures districts are taking to ensure safe, clean air within buildings.
To answer these questions the Seattle Times Education Lab contacted public health officials and facility managers and administration at Seattle Public Schools. Their recommendations paint a good roadmap for other districts to follow throughout the pandemic and beyond.
One recommendation was for campuses to introduce as much fresh air to the interior as possible to lower the concentration of particles containing the coronavirus. Concurrently, run air filtration and ventilation systems at full capacity. Since reopening buildings, the Seattle school district has increased its HVAC settings from 30% to 100%.
The school district also suggested that teachers open classroom windows as much as possible for a “low-cost option.”
To complement these practices, schools can purchase stand-alone high efficiency particulate air (HEPA) filters. They’ve been recognized at effectively capturing COVID viruses, and although they are expensive, have been placed in Seattle school buildings that have few windows and/or HVAC issues. The jury is still out on their effectiveness at removing particles from the air, but there are studies underway.
At five schools within the district, for example, $500 HEPA filters are being tested in 1,000-square-foot classrooms.
“As we gain more information about COVID transmission, and particularly the size of the particles that may be the most contributing to transmission, we can understand how efficiently the HEPA filters might remove those,” says project lead Elena Austin, assistant professor of environmental and occupational health sciences at the University of Washington.
Improving ventilation is never a bad idea, but it’s natural for people to wonder how well these extra measures are working. This requires careful monitoring of the systems and consistent measurements of the air quality. In Seattle, school facility directors are utilizing a device called a balancing hood to measure the output of air from HVAC systems, aiming for 25 cubic feet of airflow for every person within a defined, enclosed space. Additionally, the district uses a device to gauge fresh air levels, making sure CO2 is below 1,000 parts per million.
Seattle is one school district that’s following guidelines set by a national panel of HVAC experts, having replaced nearly all of the air filters in building HVAC systems. It’s an important move not only for the health and well-being of staff and students, but also because some teachers unions now have HVAC and air quality provisions written into their contacts. Seattle schools, for example, are required to provide a copy of classroom HVAC reports if an educator requests them.
