During the winter in colder climates, schools and universities face heightened challenges in maintaining the health of building occupants because students, faculty and staff spend more time together indoors. Problems with HVAC systems can trigger a host of health problems, such as the airborne spread of viruses and bacteria, as well as inducing asthma and allergies. In turn, these medical conditions increase absenteeism and reduce academic performance. The U.S. Environmental Protection Agency (EPA) says improvements in school environmental quality can enhance academic performance, as well as teacher and staff productivity and retention.
High-quality air filters play a critical role in ensuring healthy learning environments. Read on to learn about the significance of indoor air quality (IAQ) in educational settings, the decision-making process for operating effective HVAC systems and practical solutions for combating winter illnesses through advanced air filtration technology.
Why IAQ Matters in Educational Settings
Poor IAQ has a significant effect on academic performance. Research shows that high levels of indoor air pollution and poor ventilation negatively affect all nine cognitive function domains that are essential for learning and performing complex tasks:
- Basic Activity Level Overall decision making.
- Applied Activity Level Making decisions oriented toward overall goals.
- Focused Activity Level Focusing on the current task or situation.
- Task Orientation Making decisions that contribute to task completion.
- Crisis Response Planning, strategizing and staying prepared in emergency situations.
- Information Seeking Gathering necessary information from a variety of available sources.
- Information Usage Using provided and gathered information to reach goals.
- Breadth of Approach Considering multiple dimensions in decision-making to achieve goals.
- Strategy Optimizing information to reach well-integrated solutions.
According to the American Lung Association, children in classrooms with higher outdoor air ventilation rates and cleaner IAQ tend to perform better on standardized tests compared to those in poorly ventilated classrooms. This improvement is attributed to lower carbon dioxide levels and a reduced risk of infectious disease transmission. Unfortunately, the same studies revealed that classroom ventilation rates often fall below the minimum standards required for healthy indoor air. Moreover, many schools have outdated or failing HVAC systems in need of upgrades.
How Poor Air Quality Impacts Health and Wellness
Insufficient ventilation and air filtration in classrooms and other densely occupied spaces allow airborne pathogens to accumulate, heightening the risk of illness transmission. Winter in cold climates exacerbates IAQ challenges due to reduced ventilation from closed windows and doors and extended periods of indoor activities that enable contaminants to build up.
According to the American Society of Microbiology, aerosols — minute airborne particles capable of carrying viruses — serve as a pathway for viral transmission within buildings. These microbe-laden aerosols can originate from various sources, including breathing, and result in illness.
Unlike larger respiratory droplets, which are heavier and tend to fall from the air relatively quickly, aerosols can linger in the air for minutes to hours, extending the window of potential exposure. This risk is influenced by factors such as air filtration, circulation and ventilation within a space. For example, schools may have higher concentrations of airborne pathogens due to the presence of large groups of people gathered for extended periods, often with different groups of people cycling in and out of rooms, This frequent turnover means that new individuals may be exposed to lingering aerosols, while also potentially introducing additional pathogens. Together, these factors create conditions that can facilitate the spread of airborne illnesses in schools unless effective ventilation, air filtration and hygiene practices are in place.
The movement of hundreds to thousands of students, teachers and staff through classrooms, cafeterias, laboratories, lecture halls, shared recreational spaces and dormitories constantly introduces particulate matter—such as dust, pathogens and mold spores—into the air. This pollution is further dispersed throughout the space by foot traffic and the HVAC system. Without proper air filtration and ventilation, these airborne contaminants can circulate unchecked, posing health risks to everyone in the facility.
Who Makes HVAC and Clean Air Decisions in Schools and Universities?
To ensure good IAQ several key stakeholders at schools and universities must work together to define and execute effective air quality programs. Facility managers and maintenance supervisors oversee HVAC system performance, while CFOs and business administrators balance costs with efficiency. Other personnel that might be involved include building engineer, operations manager, purchasing agent environmental health and safety manager, and school wellness center director.
Clean Air Strategies
IAQ strategies at schools and universities should prioritize the best practices in ventilation and air filtration to reduce airborne particles, volatile organic compounds (VOCs) and other pollutants that degrade air quality. Ventilation systems play a critical role in maintaining healthy indoor environments by removing stale air and introducing fresh air, effectively diluting and displacing contaminants. Meanwhile, air filters complement ventilation by capturing airborne pollutants, preventing them from circulating within the environment.
Given the diversity of buildings and spaces on school campuses, a one-size-fits-all air filtration solution is not effective. Instead, a customized approach is essential. This involves evaluating the type of air handling equipment in use, local environmental conditions, occupancy levels and the specific requirements for compliance with state, local and school regulations. This tailored strategy ensures the optimal selection and performance of air filters across various facilities.
Decision-Making and Implementation Challenges
Decision-makers responsible for IAQ in schools and universities face significant challenges as they work to create healthy, safe learning environments. Budget limitations are often a primary concern, with many institutions struggling to secure funding for IAQ improvements amid competing demands for resources. For example, public schools frequently face tight budgets, leaving limited room for investment in modern HVAC systems or air purification technologies. Balancing short-term costs with long-term benefits can be challenging when initiating IAQ improvements.
Many school and higher-education administrators, teachers, staff and parents may lack a full understanding of the critical role IAQ plays in student health, learning and overall well-being. Awareness campaigns and educational initiatives are essential to highlight these connections. However, progress can be hindered by resistance to change, fear of classroom disruption or skepticism regarding the effectiveness of upgrades.
Although federal U.S. agencies like the Centers for Disease Control and Prevention (CDC) and the EPA offer guidance, there is no standardized national policy addressing IAQ in schools. State and local regulations vary significantly, leading to uneven implementation.
School facilities often face the challenge of managing multiple HVAC systems, each requiring consistent upkeep. Even in schools with appropriate HVAC systems, proper maintenance — such as replacing filters, cleaning ducts and monitoring performance — is critical. Unfortunately, these tasks are frequently overlooked due to staffing limitations or competing priorities.
These issues highlight the need for increased awareness, stronger policies and adequate funding to improve IAQ in educational environments.
Strategies for Success
Consulting with an air filtration expert who specializes in educational facilities can help identify the best strategies for HVAC filter selection, replacement and preventive maintenance. These measures not only improve IAQ but also reduce long-term costs. Such collaboration will also help to ensure that the air filters are properly rated to capture a range of particle sizes, including large, small, nuisance and hazardous particles. Even the most advanced HVAC systems cannot effectively purify the air without correctly selected and installed filters designed for the specific application.
How to Choose the Right Air Filters for Educational Facilities Institution
Selecting the right air filters for educational facilities is a crucial step in maintaining a healthy and productive environment for students, staff and visitors. For optimal performance and cost-efficiency, facilities managers should assess their current HVAC system capabilities, evaluate specific air quality requirements, and implement appropriate air filtration solutions tailored to each area’s function and occupancy level. Consider the following steps to guide informed decisions for improved IAQ and system efficiency.
Assessment
- Identify potential pollutants (e.g., dust, allergens, volatile organic compounds).
- Evaluate current HVAC capabilities.
- Review system design and efficiency.
- Assess airflow capacity and compatibility with high-efficiency filters.
- Analyze air quality needs based on building usage and occupancy.
- Determine the frequency and ease of filter replacement.
- Evaluate the availability of resources for preventive maintenance.
Recommendations by Space Type
Non-Critical Spaces
- Examples: Offices, hallways, and common areas.
- Recommendation: Use standard filters capable of capturing common airborne particles like dust and pollen.
Occupied Areas
- Examples: Classrooms, lecture halls and study spaces.
- Recommendation: Use air filters designed for final-stage filtration to ensure clean, breathable air for occupants.
Critical Spaces
- Examples: Laboratories, research facilities and healthcare training rooms.
- Recommendation: Use HEPA filters or equivalent high-efficiency options to capture fine particles and hazardous contaminants, ensuring a sterile environment where required.
Using High-Quality HVAC Filters
There is a common perception that improving IAQ is too expensive for schools, particularly those with limited budgets. While certain upgrades may require upfront investment, schools can adopt cost-effective strategies, such as regular system maintenance and the use of long-life air filters. These practices can reduce replacement frequency, lower energy consumption and enhance overall system efficiency.
In educational facilities, it is common to use multiple HVAC systems, each fitted with several air filters. Budget limitations often lead staff to select the most affordable filters that meet basic operational needs. However, this cost-conscious approach can backfire, as low-cost filters tend to clog quickly, restrict airflow and consume more energy. As a result, these filters often need to be replaced three to four times annually, leading to substantial ongoing expenses.
A more cost-effective air filtration strategy for schools involves investing in long-lasting, high-efficiency filters. Although these filters have a higher upfront cost, they maintain superior performance over an extended period, requiring far fewer replacements than standard filters. Over time, this significantly reduces the overall expenses associated with filter management compared to the frequent replacement of cheaper, less durable options.
In addition, long-life filters are designed to optimize airflow, reducing strain on HVAC systems and improving energy efficiency. These performance benefits help to lower energy consumption and utility bills and decrease the labor required for system maintenance due to the filters’ extended service life. Additionally, the reduced replacement frequency minimizes landfill waste, supporting more sustainable operations.
What Makes a High-Quality Filter?
Air filters are rated on their ability to trap small particles, using the MERV (Minimum Efficiency Reporting Value) system. Ideally, schools and universities should use air filters with a MERV rating between 13 and 16, and use filters labeled with a MERV-A rating. Filters indicating their MERV A value means they will maintain that efficiency value for their entire service life.
High-efficiency particulate air (HEPA) filters can capture a minimum of 99.97% of particles as small as 0.3 microns. Ultra-low penetration air (ULPA) filters remove 99.999% of particles down to 0.12 microns, offering an additional layer of protection for the most critical environments.
Air filtration experts frequently suggest a multi-stage filtration system incorporating prefilters in the first stage up to MERV 13A filters and final filters in the second stage up to MERV 16A. If the system is capable and designed with the specialized frames required to hold HEPA filters, a three-stage system may be required. These multi-stage units are more effective at removing contaminants like allergens, mold and odors. This approach helps to achieve optimal air purification and is cost-effective because it extends the lifespan of the final filters. As a result, maintenance and operational costs, including energy expenses, are reduced, and the time between filter replacements or cleanings is extended.
Camfil Air Filtration Solutions Routinely Used in Schools and Universities
- Air filters rated a minimum of Merv 13/13A to capture an average of 85% of particles 1 micron and larger installed in HVAC systems.
- 30/30 Dual 9 or Farr 30/30 panel filters for prefiltration in multi-stage units.
- AQ13 panel filters for single stage units configured to hold air filters no greater than 4-inches in depth and supplying air to human occupied, but non-critical spaces such as offices.
- Durafil ES3 V-bank style air filters for final filters in multi-stage units supplying air to human occupied or production areas not requiring HEPA filtration.
- Absolute VG V-bank style filters for areas where up to 99.99% @ 0.3 micron HEPA filtration is required and the air handling unit is configured for box-style HEPA filters.
- XH Absolute filters in an all-metal frame for areas where up to 99.999% @ 0.3 micron HEPA filtration is required and the air handling unit is configured for box-style HEPA filters.
- Megalam Panel Filters for areas where panel style HEPA and ULPA (99.99% @ 0.3 micron up to 99.9995% @ MPPS) filters are required.
- CamCleaner CC500 portable air purifier with HEPA filtration.
Prioritizing IAQ is essential for fostering healthier learning environments in schools and universities. High-quality HVAC filters are a cost-effective, long-term solution to combating airborne illnesses and reducing absenteeism.
Contact Camfil today for expert guidance on improving IAQ at your institution.
¹ Indoor Air Quality in High Performance Schools, EPA, https://www.epa.gov/iaq-schools/indoor-air-quality-high-performance-schools#how
² Everything You Need to Know About Air Quality in K-12 Schools for the 2024-2025 Academic Year, Camfil, https://cleanair.camfil.us/2024/10/09/everything-you-need-to-know-about-air-quality-in-k-12-schools-for-the-2024-2025-academic-year/
³ Air Quality Considerations in Schools for the 2023-2024 School Year, Camfil, https://cleanair.camfil.us/2023/08/11/air-quality-considerations-in-schools-for-the-2023-2024-school-year/
⁴ How Your School’s Indoor Air Quality Affects Health and Learning, American Lung Association, https://www.lung.org/blog/schools-indoor-air-quality-faqs
⁵ How Viruses Spread Indoors and What to Do About It, American Society of Microbiology, https://asm.org/articles/2023/november/how-viruses-spread-indoors-what-to-do-about-it
⁶ Best Air Filters for Universities and Colleges – How This Swedish Air Filtration Company is Helping American Colleges Boost Air Quality and Safety, Camfil, https://cleanair.camfil.us/2025/01/15/best-air-filters-for-universities-and-colleges-how-this-swedish-air-filtration-company-is-helping-american-colleges-boost-air-quality-and-safety/
⁷ Strategies to Improve Indoor Air Quality Throughout the University Campus, Camfil, https://cleanair.camfil.us/2024/08/28/strategies-to-improve-indoor-air-quality-throughout-the-university-campus/
⁸ Overcoming Barriers to Healthy Indoor Air Quality in K-12 Schools, Camfil, https://cleanair.camfil.us/2024/06/13/overcoming-barriers-to-healthy-indoor-air-quality-in-k-12-schools/
