The quality of the air that teachers, students, and staff breathe in school buildings every day impacts teaching and learning. For decades, if not longer, research has shown that poor indoor air quality (IAQ) in schools can increase absenteeism for students and teachers by worsening respiratory conditions like asthma. It can bring on severe headaches and drowsiness. During the pandemic, air ventilation was found to play a role in the spread of COVID-19. Recent studies, including one released by the Harvard T.H. Chan School of Public Health earlier this year, provide evidence that better IAQ plays a role in improving student achievement and teacher retention.
Despite evidence of the known benefits of improved air quality and its role in the spread of diseases such as COVID-19 and the flu, many school districts have been slow to respond. Public schools’ aging infrastructure, with many buildings more than a century old, is partly to blame. Another factor is the lack of money available for school districts to deal with environmental issues such as IAQ. Faced with overall rising costs, many districts deferred addressing the issue.
Through local expertise, federal and state grants, university partnerships, contributions from the business community, and information and support from the U.S. Environmental Protection Agency (EPA), many districts are finding ways to improve air quality in their schools.
When working to improve air quality, size matters. A large district with numerous buildings and facilities will have different challenges and requirements than a smaller district with two or three buildings. All districts can learn lessons from the experiences of both large and small systems on air quality management.
Pre-pandemic attention to IAQ
The EPA had been working for decades to help school districts address IAQ with its Tools for Schools program, and some states require school districts to protect children from harmful airborne pollutants.
However, for many school districts, the COVID-19 pandemic was the first time IAQ came to their attention. When the pandemic hit, many school districts were unprepared to ensure indoor air met health and safety standards.
Unlike many other school systems, Boston Public Schools (BPS) was prepared. In 2014, the district hired a full-time sustainability manager in the facilities management department, and by 2020 it had expanded to 15 full-time employees working in three divisions: sustainability, environmental, and energy. The school board created policy to ensure that every BPS student attends “a healthy and sustainable school.”
The school system’s environmental division is charged with “monitoring the environmental quality of BPS buildings and properties, with an emphasis on improving air quality within classrooms, utilizing simple integrated pest management techniques, managing asbestos, and testing all water sources used for drinking, food preparation, or medical services.” The environmental division staff members and their department head were the early champions of what would become a well-respected IAQ monitoring program.
BPS’ pandemic response
BPS educates nearly 50,000 students in 130 buildings that include 119 schools. The task of launching a pandemic emergency response in a school district of this size was monumental.
Fortunately, when the pandemic hit, the team in place was qualified and committed. Katherine Walsh was the head of the sustainability, energy, and environment department, and came to the district with the ideal combination of education and experience to lead the team. Her staff included a certified industrial hygienist who was a strong advocate for managing IAQ. Another team member had experience monitoring buildings in the private sector.
The team members were deemed essential workers during the pandemic. They had two main goals. One goal was to develop systems to ensure all buildings met pandemic state and federal guidelines that were frequently changing. They also worked to address community concerns regarding the efficacy of the IAQ plans to keep staff and students safe upon returning to the buildings.
They developed an Indoor Air Quality Monitoring and Response Action Plan to monitor all district buildings. The various designs of the district buildings made the task challenging. Some were equipped with central heating, ventilation, and air conditioning (HVAC). Others had operable windows with limited ventilation. Another group of buildings had operable windows and no mechanical ventilation.
“These were duty-bound, special people who were truly dedicated to the health and safety of our schools,” Walsh, currently assistant director of planning, engineering, sustainability, and environment for the district, says of her team. “At the time we didn’t realize that we were doing something remarkable. We were just trying to do the best possible job for our community.”
Two billion data points
The team worked on a comprehensive solution that would provide actionable data to ensure BPS could track and respond to harmful or unacceptable IAQ conditions.
About 4,300 air quality sensors were installed in all classrooms, nurses’ offices, and main offices. A roof-top unit was installed on every school building to measure outdoor air as a baseline per location. Each sensor records measures of IAQ, including carbon dioxide, carbon monoxide, and airborne particulates.
A ROOF-TOP OUTDOOR AIR SENSOR AT A BOSTON PUBLIC SCHOOL.
BPS followed federal, state, and local recommendations on IAQ and ventilation in schools. To keep the community informed, the district created a public dashboard (https://bostonschoolsiaq.terrabase.com) that allows community members access to the data from each sensor. That access includes the ability to download a 30-day report that is searchable by the rooms in every school.
BPS developed a research partnership with Patricia Fabian, associate director with Boston University’s Institute for Global Sustainability, to process the data collected from the monitors. She and her colleagues analyzed trends, wrote research papers, and developed a community education program.
The public became so comfortable with—and proud of—the public data that its value was recognized beyond the threat of COVID-19. The teachers union has embraced the program, and BPS and city leadership never entertained a notion of eliminating efforts to monitor and manage air quality once federal pandemic support funding such as ESSER ended.
While ESSER money was used to connect the IAQ sensors to the building management system, the district sought other sources of funding to extend their work. They won a $15.4 million grant from the Massachusetts Department of Elementary and Secondary Education to design and install new mechanical ventilation systems in three non-mechanically ventilated elementary schools. They added facilities staff to support improving indoor environmental quality.
One result of their efforts: The district was awarded Best in Class – Energy Efficiency Plus Health in 2023 by the U.S. Department of Energy’s Efficient and Healthy Schools Campaign.
Using post-pandemic data
Although the COVID-19 pandemic is hopefully behind us, BPS continues to monitor and collect data on IAQ. The district uses the data in various ways, including identifying areas to adjust in its long-term facilities plan.
By analyzing the collected information, the Planning, Engineering, Sustainability, & Environment team can adjust classroom temperatures when needed and decide about school closures during extreme heat or cold. They can increase fresh air during school events with high emissions and identify activities that make IAQ worse, such as spraying aerosols. Teachers are empowered to monitor IAQ in their own classrooms and adjust or report issues. District leadership can use the data to educate the school community about the importance of paying attention to IAQ in schools.
The district continues its work in improving IAQ for its staff, students, and school community. The facilities staff have input in the design of all new buildings and major renovations. They connect with school staff in buildings that lack mechanical ventilation to show them how to improve IAQ in their schools.
BPS leadership seeks to ensure that their research can produce practical solutions for schools. The partnership with Boston University Public Health produced a study that used the district air quality data. The study results are transforming sensor data into research data. They include data analysis and reporting, addressing inaccuracies in data due to calibration, connectivity, and power issues. The information also is used to develop IAQ communications materials for the community, including air quality factsheets.
A small school system tackles air quality
Large districts like Boston, with many buildings, must approach monitoring IAQ on a large scale. Small districts face their own challenges with IAQ monitoring and require different approaches. Lack of access to resources, including nearby university or business partners, adds to those challenges.
Lakes International Language Academy (LILA) is a prekindergarten to 12th grade International Baccalaureate World school that serves 1,400 students in Forest Lake, Minnesota. It has three campuses: a kinder center, a lower school, and an upper school.
In fall 2024, leaders with the public charter school reached out to the American Lung Association and Carrier Global, an HVAC manufacturing company, for help with assessing air quality in its buildings. This partnership allowed the school to install 137 continuous air quality monitoring sensors throughout the three campus sites. Each sensor measured carbon dioxide, particulate matter, and other features. Then the data was filtered to include only the buildings’ operating hours. Results were analyzed and a detailed report on the findings was provided to LILA.
OPENED IN 2024, BOSTON PUBLIC SCHOOLS’ JOSIAH QUINCY UPPER SCHOOL WAS DESIGNED TO
PRIORITIZE IAQ. IT HAS EARNED THE LEADERSHIP IN ENERGY AND ENVIRONMENTAL DESIGN (LEED)
PLATINUM CERTIFICATION. (PHOTO CREDIT: HFMH)
In addition to measuring air quality with monitors, building walkthroughs were conducted on two campuses (kinder center and lower school) using EPA’s Tools for Schools Action Kit checklist. Lower school and kinder center faculty completed electronic surveys using a modified version of the EPA’s Tools for Schools “Teachers’ Classroom” checklist.
At the onset of the project, key interviews were held to collect baseline information about IAQ history, practices, and procedures.
10 Tips from Boston Public Schools
BPS has just updated its IAQ Management Plan in a 22-page document that other districts can use as a launchpad for their own plan. Katherine Walsh, the assistant director of planning, engineering, sustainability, and environment for BPS, offers these tips for improving air quality in your district:
1. Communicate early and often with the community. Use data to advocate for resources and make decisions about buildings. A technical solution must be coupled with strong community engagement that explains the “why”: the health of our students and staff.
2. IAQ issues exist. For districts concerned about opening themselves up to liabilities if they get started with IAQ management, understand that the issue is real, and it is better if the district finds it and takes action first.
3. Regulations are coming. More states are passing regulations regarding IAQ in schools. Be prepared.
4. Pilots are underrated. You don’t have to do what Boston did and start monitoring every classroom on a public dashboard. Start with portables or some other subset of classrooms and work your way up.
5. Smart staffing. Every school district should either have a staff member who is a certified industrial hygienist or have a contract with a vendor who can provide that service. At a minimum, have an environment, health and safety division in-house. In addition, have someone on staff who can communicate technical issues in a nontechnical way, so the district is able to effectively communicate about IAQ with all community members and school vendors.
6. Teamwork. Gain from everyone affected when developing an IAQ management plan.
7. Superintendents talk. The superintendent should communicate directly with the subject matter experts in IAQ, health and safety, no matter where they fall in the chain of command. Find out what they know about the health of the buildings and what resources they need to improve them.
8. Understand that you are not alone. Get involved in national networks that are working on IAQ. Talk to your K-12 counterparts in the region and across the country.
9. Don’t let the perfect be the enemy of the good. If your district is just beginning to work on IAQ, the community may not have context to determine if this is good news or not. That may cause conflict. Be open and remind the community that this is a journey of continuous improvement.
IAQ data results
The data showed that temperature and carbon dioxide (CO2) levels measured by IAQ sensors occasionally fell outside of the recommended levels. One out of four classrooms registered temperatures outside of the recommended range of 20% of the occupied time or more.
Some classrooms (34%) in the kinder center and lower campus experienced elevated levels of CO2. This occurred 20-27% of the occupied time, primarily between the hours of 2 p.m. and 5 p.m. While it is not surprising that CO2 levels elevate throughout the school day, this result revealed an opportunity to adjust HVAC systems to increase ventilation rates.
Satisfactory classroom conditions were found during the walkthrough assessments. Classrooms were well-maintained and free from sources of pollution, including trash, animals, active leaks or condensation, or pests. A few classrooms had upholstered chairs, and some cleaning supplies were present, including antibacterial wipes.
Two types of odors were identified through the school assessment. A couple of teachers reported occasional odors from vehicle exhaust, but these conditions were not observed during building walkthroughs. The vehicle exhaust could be explained by car emissions seeping indoors during parent drop-off or pick-up idling times. There was a notable odor from a laminator in one workroom, indicating the possible presence of volatile organic compounds.
The district’s efforts yielded results. LILA’s clean air exchange rate on all three campuses now is higher than CDC recommendations. The district has institutionalized practices for monitoring and maintaining systems that impact IAQ. Staff assesses and maintains HVAC systems, monitors the number of air exchanges daily, and changes air filters three to four times per year. They regularly conduct asbestos inspections and have tested radon and mold within the last five years.
What LILA learned
This comprehensive assessment yielded valuable insights that can inform future air quality management strategies for LILA, which can apply in other schools.
A multifaceted approach to assessing IAQ is important. Teacher surveys and building walkthroughs provide contextual insights. The combination of sensor data with teacher surveys and building walkthroughs provided a comprehensive understanding of IAQ. Teacher surveys offered valuable insights into potential pollution sources and perceived IAQ issues, while building walkthroughs confirmed classroom conditions and identified potential problem areas.
Using continuous sensors provided granular, real-time data on air quality conditions. This data has allowed for a more precise understanding of IAQ fluctuations throughout the day and across the three campuses. Facilities staff emphasized the value of this data for making informed decisions regarding HVAC adjustments and outdoor air intake management.
While the overall IAQ at the campuses was satisfactory, the identification of specific pollutant sources, like vehicle exhaust and cleaning supplies, demonstrate the importance of targeted interventions. Addressing these sources through strategies like vehicle idling policies and district-approved cleaning products can further enhance air quality.
LILA’s experience in navigating resource constraints while enhancing IAQ practices underscores the need for strategic planning and prioritization. Schools with limited resources can leverage data-driven approaches and targeted interventions to maximize the impact of their IAQ management efforts.
This work was funded as a case study partnership with the American Lung Association through a grant from Carrier. The American Lung Association provided the IAQ walk-through expert, school staff survey process, technical assistance, etc., and the continuous air quality monitors were donated to LILA.
School systems face different challenges because of their size. However, regardless of size, districts that embark on this journey will be improving the quality of education for students and the working conditions for teachers.