Poor air filtration in schools is driving absences and tanking productivity, but the fix is simple

As summer break releases students from schools across the country, we have an opportunity to fit classrooms with a simple and cost-effective solution to reduce skyrocketing absenteeism and address tanking American productivity.

So, what's stopping schools from implementing this safe, effective and free countermeasure to combat airborne infections, reduce classroom pollution and even improve academic performance? The answer is simple: Not enough parents are demanding it.

At the start of the pandemic, keeping children at home slowed the American workforce, which might be why the Biden administration committed to getting kids back into schools. But although the pandemic has ended for most Americans (at least those who are not elderly, immunocompromised, or too young to find easily accessible vaccines), US schools have still seen staggering increases in chronic absenteeism, with COVID playing a significant role. At the same time, record numbers of parents have been missing work to take care of sick kids, which has been associated with a notable decline in American productivity.

Many are quick to point out that the earliest and hardest-hitting flu and RSV season — and not COVID alone — was responsible for filling children's hospitals this past fall. But this overlooks findings as recent as May indicating that COVID damages T cell response, producing immune impairment that contributed to this surge in illness. This may explain why many parents find themselves echoing what Dr. James Antoon of Monroe Carell Jr. Children's Hospital at Vanderbilt has said: "since September [kids have] been sick with back-to-back viruses."

Some states, including Alabama, have put forth legislation to add thirty calendar days to the academic year with the stated goal of fighting learning loss — but must we accept sickness and record-high chronic absenteeism rates as a permanent condition for our children? Maybe it's time to dust off the largely-neglected air filtration recommendations schools were advised to implement at the start of the pandemic.

It's not a new concept, but the past three years have taught us a lot more about how powerful clean air can be against airborne viruses. Dr. Joseph Allen at the Harvard School of Public Health has gone as far as to say that, "the person who designs and operates your building has a greater impact on your health than your doctor."

In 2020, ventilation and filtration were recommended by experts in public health, building science and HVAC engineering. The American Society of Heating, Refrigerating, and Air-conditioning Engineers (ASHRAE)'s official position is that their own standard is "not meant for infection control" and that standard ventilation levels are "significantly lower than levels recommended" for our current challenges. Under pressure from the White House, ASHRAE has approved a new indoor air quality standard that is, in fact, even more aggressive than many of the recommendations heretofore.

Broadly speaking, to reduce airborne infections, experts recommend that schools introduce outdoor air, use in-room portable HEPA filters and upgrade HVAC filters. Healthy air in schools is a long-term solution with broad health benefits, which can be key to managing allergies, asthma, and preventing airborne infections. With increased wildfires as a result of climate extremes, air filtration becomes an essential tool in classroom resilience. No matter the contaminant, cleaner air has been linked to improved cognitive function and academic performance.

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But how much is enough clean air for buildings? Guidance co-authored by ASHRAE and the American Council of Government Industrial Hygienists (ACGIH) suggests introducing six to twelve air changes per hour of outdoor air. In most classrooms, this would be one to two cubic feet per minute (CFM) of airflow for every square foot of classroom space.

Some studies associate this amount of airflow with more than 80 percent reductions in exposure and transmission at the bottom of this range. The American Industrial Hygiene Association argues for this same range, while noting that the lower end may be inadequate for densely occupied spaces with one or more infected occupants — in other words, school classrooms. Even dropping down to the CDC's recent recommendation of five air changes per hour still may afford a 65 to 75 percent reduction in exposure according to CDC and CERN.

The Lancet COVID-19 Commission gives alternate recommendations about how much airflow should be afforded to each occupant, which is a metric that building operators often prefer. Their best prescription? At least 30 CFM per person. Lower threshold guidelines from the WHO and CDC in 2020 amount to roughly 20 CFM per person, which is still much higher than what is required by International Mechanical Code. One analysis indicates that these ventilation rates can reduce infection risk by 70 to  80 percent in classroom spaces.

With the emerging evidence that COVID infection disrupts immune systems, there's even more reason to protect our youngest population from repeat infections. And though high-quality masks are still an important and necessary tool, especially for those of us who are immunocompromised, many children are unable — or unwilling — to mask for long periods of time. Plus, with lunch and water breaks, consistent masking has become an almost impossible request. This might partially explain why the White House has undertaken a long-term strategy of pressing hard for ventilation and filtration.

We have the technology to slow transmission of airborne viruses. Some hospitals and office buildings already use this technology to prevent patients, employees and conference participants from getting sick. And for schools, it would be free: in 2021, the Federal Government announced it would provide $123 billion in emergency relief funds, enough to cover air filtration upgrades for public and private schools nationwide. Schools can use Elementary and Secondary School Emergency Relief Fund (ESSER) funds as late as September 2024, or later if they sign a contract before then.

As of March, these funds were only 36 percent spent, according to data compiled and published by FutureEd. It is critical for parents to stand up now as ESSER stakeholders and advocate for schools to make the important connection between air quality and attendance, as well as academic performance.

Schools that aren't sure where to begin can receive free, expert technical assistance from the US Department of Energy's Efficient, Healthy Schools Campaign. This program, in partnership with the EPA, can help decision-makers at US schools make the best use of Elementary and Secondary School Emergency Relief and Inflation Reduction Act funds.

This summer is an ideal time for schools to introduce quality air filtration in classrooms so that next year, parents can feel confident their children will be less likely to miss school days and spread illness to classmates, family and communities. Improving air filtration will not only help stop transmission of current viruses, but it will also protect American children from future pandemics.

We ask our children to wash their hands. We ask our doctors to wear gloves. It's time that we ask our schools to clean the air.