Here’s a really interesting report that seems to have gotten lost in the shuffle amid all the disruptions this pandemic spring.

Article in Ed Week

The original paper

The Aliso Canyon gas leak in Southern California was big news a few years ago. As a result, a dozen and a half elementary schools in the area were provided high quality air filtration in every classroom. Measurements were made to assess levels of outdoor pollutants entering the classrooms, and children’s math and reading test scores were also analyzed and put through various comparisons.

Very little outdoor pollution made it into the classrooms, as it turns out, but the filters cleaned up typical indoor pollution. As air quality improved in the schools that received the filters, so did the students’ test scores. A lot. Test scores improved so much, the benefit was “equal to the learning benefits from reducing class sizes or providing intensive tutoring.” While the researchers noted a drop in illnesses and absenteeism among occupants of these classrooms, the improvements could not be attributed to those benefits alone.

Test scores improved so much, the benefit was “equal to the learning benefits from reducing class sizes or providing intensive tutoring.”

While the article and the original paper both bear reading, the benefits of better air quality in schools is not news. Prior research already linked air quality in schools with student test scores and achievement, and poor air quality with student and teacher illnesses and absenteeism (which are further connected to a litany of other ills).

Healthy schools = healthy kids

The EPA even developed a whole body of helpful, evidence-based resources for schools to use, their Tools for Schools, upon which many other well-researched indoor air quality management plans have been based. Indoor air quality management plans are just well-researched strategies that help make schools healthier and keep them that way.  If you want to really delve into the issue, the EPA has an indoor air quality master class webinar series which is free and definitely worth the time:
IAQ Master Class Professional Training Webinar Series

Although this research shows just how dramatically better indoor air quality can improve student performance and reduce illnesses and absenteeism in the classroom, an even greater takeaway should be that:
a) evidence already exists that schools can get such dramatic benefits from adopting indoor air quality management plans, without filtration, and often at very little cost, and
b) using filtration in addition to adopting indoor air quality management plans could be powerful tools to both reducing illnesses spread in schools and improving student achievement.

The well-researched tools to accomplish this have been available to schools, for free, for many years, yet less than half of schools have an indoor air quality management plan, despite the EPA reporting that half of schools have problems related to air quality, and despite the aging school infrastructure—the majority of schools in this country built over 50 years ago.

Although such problems can affect children in poorer districts disproportionately by compounding other factors, rich districts are not immune. Recent research in California schools found inadequate ventilation and poor air circulation (with the attendant harm to learning and student health) in the vast majority of classrooms, around 85% of classrooms they looked at, a finding that confirms previous research. They found new school sites were just as prone to having poor ventilation as older ones.

It has always been something of an ongoing tragedy that this major body of environmental health research hasn’t been recognized and adopted uniformly across the nation, because very small investments can reap such major rewards for our nation’s children.

This may be in part because adopting such plans can seem complicated and is completely voluntary, and next to no legal obligations exist in virtually any states to ensure good air quality in schools or to allow parents recourse to fix things when their children’s schools have air quality problems. I’ve had discussions with school administrators who told me frankly that they follow many regulations and they believed if adopting such plans were important, there would be a law they had to follow. I’ve had discussions with experienced environmental scientists who told me frankly (going back many years, irrespective of partisan turnover in Washington) that they are under considerable political pressure and the best way to get schools the benefits of this research is for the EPA to share what they can and make it voluntary.

And thus the fundamental problem here, a gap in understanding between environmental health scientists and school health stakeholders, including teachers, parents, students, and the doctors who care for them all, leads to an unnecessary and easily-removed health burden on our nation’s children and teachers.

How this school filter research could help students return to schools and colleges

Looking ahead to the fall of 2020, with so many uncertainties and the likelihood of both the flu and Covid-19 surging at the same time, schools and colleges are trying to cope with the staggering adjustments that will have to be made in order to safely return students to campuses.

Unfortunately, the impact on colleges is especially severe with the economic strain of many students, especially international students, staying home, deferring, or simply not going to college at all next fall.  Any livelihoods that depend on gatherings, such as live music and restaurants, travel and tourism, all stand to be hit even worse if there is another surge of infections in the fall, thus compounding the problem for colleges with the greater demand for financial aid as a large percentage of families lose jobs and income. Certainly, a coronavirus vaccine will help, but there is almost no scenario under which there will be a proven effective vaccine in place before fall, and if one is rushed and doesn’t work, or worse, has unexpected, serious consequences, it could undermine faith in other vaccines.

Attention to research like this should be part of the planning picture, because improving indoor air quality doesn’t just demonstrably improve student performance, per considerable research, it also reduces the number of infections the occupants of buildings get and pass around.

Improve indoor air quality, and you reduce the rate of infections and absenteeism, not just in those with asthma, but in everyone. Fewer children and teachers get asthma, and those who have asthma get fewer attacks. This is well-established by decades of environmental science, including specifically in schools.

Adopting an effective framework for indoor air quality management can improve air quality by more than just the simple filtration reported in this paper, and adding filters can mean even greater benefits. Especially since few people seem to be minding proper two-step disinfection, and are using detergent wipes like they’re going out of style. Such products leave residues that build up as dust and cause asthma.

CDC: Avoid disinfectant wipes containing asthmagens

According to the CDC’s Healthy Cleaning and Asthma-Safer Schools:  “AVOID DISINFECTANT WIPES  Disinfectant wipes are used regularly, but they usually contain asthmagens. “ (Substances that are known to cause asthma.) It is possible to achieve the same or better cleaning and disinfection results without causing asthma at the same time.

We all know that asthma is a risk factor when it comes to Covid-19, and people can also develop inflammation in the lungs that makes them susceptible from these same environmental influences short of having diagnosable asthma. The CDC cleaning recommendations, the two-step process I blogged about earlier, can be done—in fact, are better done—without increasing asthmagenic chemicals in the environment which can increase susceptibility to infection.

Another serious problem that schools face this fall, is that environmental scientists have also long known that when a closed up space, like a school, has been shuttered and unoccupied for a period of time, when it is reopened, the new occupants stir up all kinds of stuff that worsens air quality and causes spikes in infectious diseases and other known consequences of poor air quality. If this is not understood and addressed before schools, workplaces, colleges, and other communal spaces reopen globally in the fall, the predictable, attendant spikes in upper respiratory symptoms AND infections could cause a preventable wave of more deaths and lengthier shutdowns.

When a school has been closed up for a period of time, when it is reopened, the new occupants stir up stuff that worsens air quality and causes spikes in upper respiratory infections and other known consequences of poor air quality.

Seriously adopting indoor air quality management plans in all schools now, even without filtration, could help reduce this phenomenon, which could cause panic in the fall as schools and colleges around the world reopen for the majority of students after being closed up for so long. Filtration could reduce problems further, and it could be an important tool for allowing more normal life again as one of many tools.

From what I learned about the topic, filtration is actually a poor second cousin to implementing an indoor air quality management plan. It’s better to avoid building up unhealthy chemicals and particles in the first place than to try to filter them out, but in practice, I have observed that the easy, cheap indoor air quality management steps seem to be the hardest for people to believe work.

The EPA has done previous research with filters in classrooms, when a known environmental problem could not otherwise be remediated (mold), with good results, but they did not use commercial filters which tend to be too small and too loud. They used cabinet-sized filters that resulted in more robust filtration without adding noise to the class room environment. (Don’t quote me on this, but I vaguely remember the company involved in that work was also involved in providing the plug-in filters for this research.)

One of the reasons I brought up the question in my last post—why are people still getting sick?—and wondered if it’s possible to keep detailed data on new infections, is the possibility that a more refined understanding of exactly how people get sick in groups (or not), and how they don’t, in as much detail as possible, could help mitigate the extreme response, even mitigate the indiscriminate use of disinfectants.

Such an understanding would especially help schools and colleges understand the parameters for safe return of students. In the meantime, measures to improve indoor air quality need to become a priority, as they can be adopted while students are home, and are already proven to significantly improve student performance and reduce the spread of infectious illnesses in schools.



*I should note that while mechanical filtration can filter out viruses, it’s not necessary to do that in order to get the benefits above, such as reducing illnesses going around in schools. Simply removing the harmful chemicals (like those that come from mold growing in the environment) and particles that cause damaging health effects like airway inflammation, including “remodeling” of the upper respiratory system from chronic inflammation, is enough to improve student performance and reduce the incidences of colds and flus going around at school.  Further research would be necessary to know the best kind of filtration to get the absolute best reduction of novel coronavirus spread.