IAQ Monitoring Applications in Schools

Countless organizations have been tirelessly working to establish standards to help schools re-open.  Government and research institutions like ASHRAE, United State Centers for Disease Control, The World Health Organization, The Harvard School of Public Health and the Center for the Built Environment have been developing guidelines, adapting to research updates as they come. 

For many school administrators, it is their first time deeply considering air quality, and the recommendations have come in contrast to typical operating procedures.  As many work to implement new standards for the first time, administrators may be asking themselves questions like: 

Is it sufficient to only partially open windows?

Is my HVAC system programmed correctly to meet these new requirements?

Do I need to add portable filtration to a space, or is what I have enough?

I only have a limited budget, can I afford to take these measures?

The frustrating response is of course “it depends”, and these questions can only be answered effectively with data. 

IAQ data allows school administrators to validate system performance and gauge the effectiveness of mitigation efforts throughout a school. Real-time monitoring keeps them up to date, and informed. 

Senseware has been working with schools throughout the pandemic to assess air quality, determine infection risk, and help reopen safely.  Here’s some of what we’ve learned along the way. 

Infrastructure needs an update.

A recent report from the United States Government Accountability Office revealed that “41 percent of districts need to update or replace heating, ventilation, and air conditioning (HVAC) systems in at least half of their schools, representing about 36,000 schools nationwide that need HVAC updates” 

The initial assessment of building infrastructure was only focused on meeting the basic air quality and environmental requirements. Now that research has revealed the importance of air quality regulation in slowing the airborne transmission of the coronavirus, the need for updates is more pressing than ever.  

Schools without mechanical ventilation can operate safely under the right conditions.

A recent school Senseware worked in was designed as an open air school.  With few walls and open spaces, air could move freely from one space to another.  Now with Coronavirus as a factor, special attention was paid to ventilation to see if what was in place would be sufficient enough to optimize the injection of fresh air into the space.

Senseware IAQ monitors throughout the space revealed that through opening windows, and strategically placing fans they were able to keep ventilation rates high.  This required other adjustments by students and staff to layer up for warmth on cooler days, but continue to learn in person, safely.  

CO2 is an effective proxy for ventilation. 

Before Senseware was focused on Coronavirus mitigation efforts, we were helping schools assess their current HVAC systems to determine what upgrades were required. In some cases, the consequences of outdated systems were shocking. 

After installing IAQ monitors in several classrooms in an Atlanta area school, we measured CO2 levels throughout the day. We found that levels in some rooms reached peak contamination levels of 4,000 ppm.  An acceptable target for peak CO2 levels in a classroom environment would be around 1,000 ppm.  When levels reach 2,000 ppm, we consider that alarming and an impediment to student learning. CO2 levels were high enough in this school to cause physical side effects including headaches, insomnia and nausea. 

CO2 monitoring has long been important for assessing the safety of the environment, but it’s more important than ever.  Measuring CO2 levels serves as an effective proxy for ventilation in a space.  When ventilation is not sufficient, Senseware can make recommendations to increase ventilation, and decrease occupancy, resulting in a much safer environment for all. 

Different spaces have different needs. 

Libraries

Libraries present a different air quality challenge from other areas of a school, as was the case at  Saint Agnes Catholic School. As books are opened and used, particulate matter is released into the air.  To address this concern, Saint Agnes installed a roof unit with a MERV-13 (HEPA Grade) filter during their earlier HVAC renovation. Given the unique requirements of the environment, Senseware deployed an Advanced Particle Counter in addition to the standard IAQ monitors. The advanced particle counter measures particles in the air down to 0.3 microns. The resulting data allowed Saint Agnes to verify the effectiveness of their existing filter, and make new improvements with Coronavirus transmission mitigation in mind.  Data revealed that filtration speed needed to be improved, and as a result portable filtration units were added to the space for improved safety.

Small Meeting Areas

Confined meeting spaces have unique ventilation challenges. As people meet, CO2 levels increase over time, along with any existing environmental contaminants.  With low air flow in these spaces, concentrations can build to unhealthy levels. Senseware IAQ data allows small meeting areas to be assessed for appropriate occupancy and meeting duration times. Advanced IAQ analytics can further be used to create temporal distancing between meetings to allow HVAC systems time to reduce the infection risk of the airborne transmission of virus pathogens.

Solutions sometimes bring bigger problems

Many schools have made dramatic changes to their surface cleaning procedures to reduce the spread of transmission.  Some of these changes have resulted in unintended consequences. Senseware IAQ monitors have revealed high Volatile Organic Compound (VOC) concentration in the air.  This is often as a result of harsh off-gassing from cleaning products. While these products make surfaces cleaner, they have an impact on air quality. Breathing in disinfectants and chemicals from cleaning products can have negative side effects, especially in children. 

After implementing changes to their cleaning products and schedules, schools can continue to monitor VOC levels to determine if the changes they’ve made are enough. 

Air quality data is a new metric for many school administrators, but a worthy one to learn.  Monitoring a few key metrics can deliver the information needed for a confident reopening strategy.