Indoor Air Quality (IAQ) is increasingly recognized as a critical tool to help address the pandemic. While building code officials, engineers and other industry professionals have considered the importance of healthy IAQ in buildings, the public is now becoming more and more aware that the air we breathe has a major impact on our health. This is especially critical for K-12 schools since they are high-density, occupied spaces with a high degree of intermingling.
This paper will explore the background of IAQ, the fundamentals to ensure good IAQ, and best practices we can utilize to help mitigate the effect of this pandemic. These practices will also help make our buildings more resilient for additional IAQ issues and future pandemics.1 Some Background Subconsciously, we all know that proper ventilation, air filtration, and air purification has a major impact on our health and wellbeing.
We have all experienced classrooms with little to no air flow, and a stale and sometimes odorous scent. Certainly, we feel relief with the simple act of opening a window just “to get air moving.” With regard to contagious viruses, the dynamic of the stale room is no different. By removing these nasty, microscopic particles (which are approximately 500-1,000 times smaller than the diameter of a human hair) from the indoor environment, we reduce the intensity and quantity of the virus and diminish its ability to infect more people.
Our ancestors knew this. In response to the Pandemic of 1918, when over 20,000 New Yorkers died2, ventilation was recognized as one of the key attributes to protecting residents from the devastation of the pandemic. According to a recent article in Bloomberg3, New York City officials dictated that building heating systems were to be designed and sized to operate with all the windows open since ventilation was key to purge the virus from indoor spaces.
As the article quotes: Health officials thought (correctly) that fresh air would ward off airborne diseases; then as now, cities rushed to move activities outdoors, from schools to courtrooms. When winter came, the need for fresh air didn’t abate. According to [heating industry expert and author Dan] Holohan’s research, the Board of Health in New York City ordered that windows should remain open to provide ventilation, even in cold weather. In response, engineers began devising heating systems with this extreme use case in mind.
What was true a 100 years ago is true today: viral spread is transmitted from person to person, with air as the most common medium. If you can clean the air by purging with fresh air, filtration, and/or air cleaning devices, you can reduce the intensity of the viral spread. Reducing the quantity of contagious particles will reduce the intensity of the viral spread.