Reimagining Air Purification in Classrooms After COVID-19

Pandemic brings renewed focus on importance of indoor air quality in schools.

From adjusting to hybrid learning models to sanitizing desks between classes to wearing personal protective equipment, the way classrooms operate has changed due to COVID-19. As the vaccine slowly rolls out across the country, faculty, parents, and students are all wondering what classroom changes are here to stay in 2021 and beyond.

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One thing that will certainly remain a top priority for the foreseeable future is maintaining clean and sanitary public places, including classrooms. Most notably, the pandemic has vastly increased awareness of the importance of indoor air quality. During the onset of the virus, it was quickly confirmed that COVID-19 is an airborne virus, and maintaining proper indoor air quality became a top concern.

Upgrading HVAC systems is one way for school systems to maintain indoor air quality, although installation can be costly and may not be feasible for all. Additionally, HVAC systems are designed to accommodate comfort by controlling humidity and temperature, not airborne pathogens such as COVID-19. Adding a high-grade air purifier to a classroom is a simple yet effective way to ensure the indoor air is free of contaminants.

When it comes to clean air in the classroom, there are four main components worth considering as educational environments continue to adapt and change to prioritize indoor air quality. These components are performance, size, sound, and design.

Growing, Thinking and Learning

Air pollution is a major health threat to children, who are particularly at risk because their lungs and brains are still developing. Children also breathe more rapidly, taking in 50% more air in relation to their body weight than adults. This puts them at greater risk and makes them more susceptible to common air pollutants like dust, smoke, and chemicals often found in cleaning products. Studies have shown that children are up to four times more likely to have significantly reduced lung function in adulthood if they live in highly polluted areas. Even further than that, air pollution can exacerbate underlying health issues. Long-term exposure has been associated with both new-onset asthma and the exacerbation of pre-existing asthma.

Because indoor air can be up to five times more polluted than outdoor air, those with children living in cities or areas with higher air pollution should consider air purifiers for their classrooms and main educational areas like cafeterias. Studies have shown that dirty air can have negative effects on cognitive development and coordination—which can have lifelong implications in terms of schooling outcomes and future careers. Clean air helps support children so they can achieve their full potential.

Air Purifiers Can Help Maintain Attendance

According to the CDC, asthma-related illness is one of the leading causes of school absenteeism, accounting for more than 14 million missed school days per year. An air purifier in a crowded classroom of sneezing students can help reduce the spread of colds and flu by filtering out bacteria and viruses. By providing clean air, schools can help students focus on the subjects at hand instead of being distracted with sneezes and the discomfort of not being able to take a deep breath.

Importance of Proper Ventilation

Another step towards improving indoor air quality in schools is to improve overall ventilation. The California Energy Commission reports that ventilation rates in most schools are below recommended levels, both in the United States and in Europe. In fact, in a California study, one in every three schools had ventilation rates that were less than half the recommended levels. A new law signed in Sept. 2020, Assembly Bill 841, set aside $600 million for public school energy improvements like improved HVAC systems.

Opening windows periodically can help balance the flow of outdoor air inside to improve air quality. Removing pollution sources can also greatly increase air quality indoors. Common sources of pollution in schools include toxic cleaners, paints, and materials with formaldehyde. The Environmental Protection Agency offers a list of technological solutions specific to air quality. On top of these efforts, using an air purifier has the potential to eliminate 99.97% of airborne pollutants with an immediate effect, maintaining optimal air quality levels in the classroom.

Finding the Best Air Purifier for Your School

There are many variables that come into play when considering an air purifier for your classroom or learning space.

  • Performance: Above all, it’s important that your air purifier maintains a certain level of performance. A single-pass filtration rate (99.97% down to 0.3 microns) is one indicator, but the best indicator is the Clean Air Delivery Rate, or CADR. This takes the single-pass filtration rate into consideration but also looks at the amount of clean air that the unit produces. The higher the CADR, the greater volume of clean air it produces. The AHAM Verifide program from the Association of Home Appliance Manufacturers (AHAM) is an independent testing program that tests for CADR and makes recommendations on appropriate room size based on this performance. Look out for products that have tested through this program to be sure you are getting a high level of performance.
  • Classroom space: Depending on how large or small your classroom is, different air purifiers can circulate air into a range of different size rooms through the CADR. Also for consideration is the Changes Per Hour (ACH). Some air purifiers will change the air in your room only once per hour, so look for those that have higher air changes per hour for better performance.
  • Sound: Some air purifiers are louder than others. Do your research before buying an air purifier. As many teachers know, anything can be a distraction for students, so consider purchasing a purifier that makes minimal noise.
  • Design: The days of bulky, obtrusive air purifiers are long gone. There are many options in the market that can easily fit within the aesthetic you are looking to achieve in your learning space.

Student and faculty health has always been a top priority for schools and will remain so as we embark on this new post-COVID-19 era. While 2020 was a stressful year for everyone, it also served as an opportunity to usher in change and prioritize health. Classrooms will continue to adapt to create the safest and most efficient learning environments.

This article originally appeared in the Spring 2021 issue of Spaces4Learning.

About the Author

Kevin Luo is a Senior Air Filtration Specialist for Blueair, a Unilever brand focusing on air purification solutions for home and professional use.