Text Version of the Interactive School IAQ Tour

Good indoor air quality (IAQ) plays a critical role in a healthy, productive learning environment for students and staff, while poor IAQ can lead to discomfort, increased absenteeism, and even long-term health issues. Schools include a range of unique spaces (e.g., classrooms, cafeterias, gyms, mechanical rooms), each presenting its own challenges and opportunities for maintaining clean, healthy air.

The graphics below highlight common IAQ problems in schools and practical solutions to address those issues. These graphic are not comprehensive of all school IAQ concerns. EPA encourages every school and school district to develop IAQ management plans that are tailored to their unique infrastructure and staff using the EPA IAQ Tools for Schools Action Kit.

For an interactive version of the information below, visit the Interactive School Indoor Air Quality Tour.

An overhead isometric view of a school with the roof cut away to show the different rooms

On this page:

Classroom
Science Lab
Nurse's Office
Art Studio
Computer Room
Cafeteria
Gym and Pool
Woodworking Shop
Automotive Shop
School Grounds and Portable Classroom
Roof
Utility Room

Classroom

Classrooms can host a range of indoor air quality issues and teachers are often the first to identify, report, and address them. Click the arrows to learn how to address common indoor air quality concerns in classrooms.

A portable air cleaner and a unit ventilator in a classroom

Portable air cleaners and classroom heating, ventilation and air conditioning (HVAC) equipment, like unit ventilators, must have their filters replaced regularly, according to manufacturer guidance. Portable air cleaners (also known as air purifiers) may also have pre-filters that need to be cleaned more frequently than the filter replacement schedule.

A prohibition sign over books stacked on a classroom unit ventilator and a checkmark over books properly stored in a bookshelf

Be sure to keep all materials, like books, off the top of unit ventilators. These objects can block the airflow, resulting in inadequate ventilation, heating, and cooling. Obstructed airflow may also put strain on the components, leading to equipment failure.

A prohibition sign over a drafty window in a classroom

Keep an eye out for drafts through inadequately sealed windows. HVAC systems may struggle to maintain comfortable temperature and humidity if outside air is leaking into the classroom. Drafts can also confuse nearby thermostats, causing them to overheat or overcool a space. Lastly, drafts can bring outdoor air pollution into the room.

Prohibition signs over a leak under a unit ventilator and mold in a ceiling tile. A laptop screen displaying EPA's mold guidance.

Any signs of water damage or mold should be immediately reported to facility staff. The water leak or humidity issue must be fixed before cleaning up the mold to prevent future mold growth. Refer to the EPA’s Mold Remediation in Schools and Commercial Buildings Guide for guidance on cleanup.

A thermostat in a classroom displaying 72 degree Fahrenheit and 40% relative humidity

To reduce the risk of mold growth and protect health, comfort, the school building and its contents, it is important that indoor relative humidity be maintained below 60%, ideally between 30% and 50%.

People installing furniture and flooring and also painting walls in a classroom

When furnishing, painting, or carpeting classrooms, consider selecting low volatile organic compound (VOC) emitting products.

Science Lab

A school laboratory with lab benches and chemistry equipment

Science labs have unique indoor air quality concerns – like chemicals and emissions from heated materials – that can be addressed with proper source control and ventilation. Click the arrows to learn how to address common indoor air quality issues in these rooms.

A school laboratory showing a safety data sheet binder stored in a bookshelf

Chemicals must be stored and handled consistent with their safety data sheets (SDS) stored onsite.

A student in a lab wearing gloves, glasses, and a lab coat. A lab fume hood that is shown venting to the rooftop.

When working with chemicals and combustion sources, staff must ensure the classroom has adequate ventilation and students are using appropriate personal protective equipment (PPE). Some laboratory work may require fume hoods with dedicated local exhaust ventilation.

A lab bench with a sink and student wearing a lab coat, gloves, and glasses

Run the water in sinks at least once a month to ensure that drain traps do not dry up, which can lead to sewer gas migrating into the classroom.

Nurse's Office

Nurse’s offices that address indoor air quality can help to contain the spread of respiratory illnesses. Click the arrows to learn how to address this indoor air quality issue.

Exhaust and supply air ductwork connected to HVAC units on the school rooftop

To reduce the spread of respiratory illnesses, nurse’s offices should have functioning, unobstructed mechanical ventilation.

A rooftop HVAC unit with a MERV 13 rated filter. A portable air purifier in a nurse's office.

Nurse’s offices may want to use MERV 13 (or higher) HVAC filters, portable air cleaners with HEPA filters, or both to capture airborne diseases in addition to allergens and asthma triggers that may be impacting students. Be sure to include the filter size, type, replacement frequency, and last filter change date in the school maintenance schedule.

Art Studio

A school art room with a kiln and photography equipment

Art studios have unique indoor air quality concerns – like chemicals and emissions from heated materials – that can be addressed with proper source control and ventilation. Click the arrows to learn how to address common indoor air quality issues in these rooms.

A vented kiln and the corresponding exhaust vent on the rooftop.

Clay studio kilns can emit particulates, volatile organic compounds, and other air pollution. Schools should use local exhaust ventilation to direct this pollution outside.

Computer Room

Computer labs have unique indoor air quality concerns – like chemicals and emissions from heated materials – that can be addressed with proper source control and ventilation. Click the arrows to learn how to address common indoor air quality issues in these rooms.

A prohibition sign over an unvented 3D printer. Other 3D printers are vented up to the rooftop.

3-D printers can emit particulates, volatile organic compounds, and other air pollution. Schools should use local exhaust ventilation to direct this pollution outside.

Cafeteria

Cafeterias can attract pests and generate odors, moisture, food waste, and trash – all of which must be managed carefully to avoid indoor air quality problems. Click the arrows to learn more.

School cafeteria stove with a range hood and a smoke detector on the wall.

Check that kitchen range hood fans meet code and are turned on when the range is in use to prevent smoke, other cooking emissions, and high levels of humidity from impacting the staff and students around the cafeteria. Carbon monoxide (CO) alarms should be installed and tested at least monthly to ensure they are working properly.

The dumpsters outside of a school cafeteria with a No Idling sign and a prohibition sign over garbage stacked outside of the dumpster.

Ensure that trash is securely contained in dumpsters. The dumpsters should be located away from any air intakes, operable windows, and doors to prevent odors and pests from entering the building.

Gym and Pool

A school gym, pool, and locker room shown from above

Gymnasiums and pools pose unique challenges to indoor air quality, including high moisture levels, mold, odors, and vapors. Click the arrows to learn how to address common indoor air quality concerns in these rooms.

A school pool viewed from above that shows ductwork for the pool ventilation system

Set up the heating, ventilation, and air conditioning (HVAC) system to move fresh air across the water’s surface and towards air exhaust vents to prevent the buildup of chloramines on top of the water’s surface.

A school pool and pool ventilation system. Labels identify that chloramines are being exhausted outside of the pool area.

The exhaust air polluted with chloramines is removed from the swimming area to the outside through a passive or active system.

A pool utility closet with chemicals stored in a closet and a ventilation system that vents to the rooftop

Pool chemicals must be stored and handled according to their safety data sheets (SDS). This includes being stored in a secure, dry area with appropriate chemical safety labeling and dedicated ventilation systems, separate from other parts of the pool area.

A locker room showing drains, ventilation ducts, and prohibition signs over mold and a leaky faucet

Locker rooms, showers, and bathrooms are at risk of water leaks and high humidity which can lead to mold growth. Be sure that they are ventilated to code and have floor drains.

A person pouring water down a floor drain and a laptop screen showing EPA's mold guidance

To ensure sewer gas does not migrate up from dried-up drain traps, add water to drains at least once a month. If you find mold, refer to the EPA’s Mold Remediation in Schools and Commercial Buildings Guide.

Woodworking Shop

Woodworking shop rooms can be the source of significant indoor air pollution – like saw dust – without careful planning. Click the arrows to learn how to address common indoor air quality concerns in these rooms.

A school woodworking shop showing the sawdust collection system that exhausts dust into a storage container outside

Sawdust should be captured and exhausted outside into a sawdust collection system.

A student in woodshop wearing personal protective equipment. A storage cabinet with a safety data sheet binder.

Appropriate personal protective equipment (PPE) should be worn when working with wood, varnishes and paints to protect from dust and vapors. Varnish and paints must be stored and handled according to their safety data sheets (SDS).

Automotive Shop

A school auto shop with cars and prohibition signs over vehicle exhaust and spilled oil.

Automotive rooms can be the source of significant indoor air pollution – like vehicle exhaust and chemical fumes – without careful planning. Click the arrows to learn how to address common indoor air quality concerns in these rooms.

A school auto shop with a car that has its exhaust vented up and out of the rooftop.

Automotive shops must meet ventilation codes to ensure that vehicle exhaust and volatile organic compounds from automotive fluids are vented outside.

Bottles of motor oil, a safety data sheet binder, and a prohibition sign over spilled oil on the floor.

Automotive fluids must be stored and handled according to their safety data sheets (SDS).

School Grounds and Portable Classroom

A school bus in front of a school with prohibition signs over vehicle exhaust and vegetation against the walls of the school.

Indoor air quality problems sometimes start outside. Click the arrows to learn how to address these issues before they come inside.

A school bus outside of a school with a No Idling sign

Implement and enforce an anti-idling policy near the school to prevent exhaust emissions from entering the building.

A hedge against a school wall with a prohibition sign over it

Ensure vegetation does not grow close to the exterior walls where it can harbor pests, block vents, and be a source of pollen or other allergens that might enter the building.

A school custodian vacuuming a long walk-off mat at a school entrance

Use long walk-off mats at all entrances to capture allergens and debris that students and staff might track into the building. Mats should be routinely deep cleaned (at least annually) to prevent them from becoming a source of indoor air quality problems.

The exterior of a school showing a portable classroom and prohibition signs over unattended lawn equipment

Exterior buildings — like portable classrooms and storage sheds — can have their own indoor air quality problems, separate from the main school building. Click the arrows to learn more.

A shed outside of a school that stores lawnmowers and fuel

Properly store all landscaping equipment, gasoline, and pesticides in a secure location away from the school.

An individual in gloves, boots, and a respirator spraying pesticides. A pesticide notification sign is placed in the lawn.

Implement an integrated pest management (IPM) plan to reduce exposure to pesticides. If pesticides are used, follow label directions, including any required personal protective equipment during application and signage after application.

An HVAC technician working on an HVAC unit, programming a thermostat, and replacing a filter for a portable classroom

Ensure that heating, ventilation and air conditioning (HVAC) systems for portable classrooms are maintained, provide adequate ventilation/temperature/humidity, and have filters replaced at a frequency consistent with manufacturer recommendations.

Roof

The school roof may be easy to overlook, but it holds critical heating, ventilation and air conditioning (HVAC) equipment and can be the source of leaks that can lead to mold growth. Click the arrows to learn more.

A school rooftop with leaves clogging the drainage and a downspout from the roof that is not directing water away from the school exterior.

Regularly clean roof drains to prevent leaks that can lead to mold growth. Ensure that downspouts drain water away from the building.

An HVAC technician servicing a rooftop HVAC unit. A MERV 13 filter in a return air duct.

Ensure that HVAC equipment is properly maintained according to a documented maintenance schedule. Replace HVAC filters at a schedule consistent with manufacturer’s recommendations. Consider using high-efficiency MERV-13 filters – if systems can accommodate them – to capture particulate pollution from pollen, wildfire smoke, vehicle exhaust, and other sources. Be sure to include the filter size, type, replacement frequency, and last filter change date in the school maintenance schedule. Consider replacing filters more frequently during wildfire smoke events.

Utility Room

A utility closet with prohibition signs over spilled water, loose HVAC filters on the floor, and spilled chemicals.

Students might not ever enter a school utility room, but if not managed correctly, these rooms can cause serious indoor air quality issues that can impact students and staff throughout the building. Click the arrows to learn more.

A utility closet with a radon mitigation system venting air from the subfloor to the rooftop

If a radon mitigation system is installed in the school, check that the fan is operating. Test rooms for radon every five years. Refer to the ANSI/AARST Radon Standards for school testing protocols.

A smoke and carbon monoxide detector in a utility closet

Ensure that smoke and carbon monoxide (CO) detectors are installed and tested according to code and manufacturer’s guidance.

Storage cabinets in a utility closet holding chemicals, a safety data sheet binder, and spare HVAC filters

Store cleaning supplies securely and consistent with label directions and safety data sheets (SDS), which should be easily accessible nearby. Ensure that you have extra heating, ventilation and air conditioning (HVAC) system air filters on hand and that they are stored in a dry location to be prepared for pollution events like wildfire smoke that may call for more frequent filter replacements.

A boiler and water heater in a school utility room

Ensure that all fuel burning appliances (e.g., boilers, water heaters, furnaces) are properly vented and regularly inspected and maintained in accordance with code and manufacturer’s guidance.