Air Quality in Schools

Why should schools be concerned about indoor air quality?

Most people know that outdoor air pollution can damage their health, but many do not know that indoor air pollution can also cause harm. U.S. Environmental Protection Agency (EPA) studies found that indoor levels of pollutants may be two to five times, and sometimes more than 100 times, higher than outdoor levels. These levels of pollutants are of particular concern because it is estimated that most people spend up to 90 percent of their time indoors. Studies consistently rank indoor air pollution among the top four environmental health risks to the public.

The Vermont Department of Health does not have information on the indoor air quality in every school in Vermont. However, the department has conducted limited indoor air surveys in about a third of Vermont schools over the past several years.

While many areas of most schools visited did not appear to have problems, almost every school had some areas with recognizable or potential problems.

Problems found include:

A 1996 U.S. General Accounting Office survey found that over 25 percent of Vermont schools reported having poor indoor air quality and 32 percent reported having inadequate ventilation systems.

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What can schools do to prevent indoor air quality problems?

Schools should take steps to prevent indoor air problems before they happen and quickly respond to any such problems that do develop. When indoor air quality problems occur, they can often be resolved by school staff, with the support of school administration and the school board. The expense and effort required to prevent most indoor air quality problems can be much less than the expense and effort required to solve problems after they develop.

All schools should implement an Indoor Air Quality Management Plan such as the one described in U.S. Environmental Protection Agency’s Indoor Air Quality Tools for Schools Kit.

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What are the consequences of indoor air problems at school?

Failure to prevent indoor air problems, or failure to act promptly, can have consequences such as:

Good indoor air quality contributes to a favorable learning environment for students, productivity for teachers and staff, and a sense of comfort, health, and well-being for school occupants. These combine to assist a school in its core mission of educating children.

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How does indoor air quality affect student and staff health?

The effects of indoor air quality problems can often be vague symptoms rather than clearly defined illnesses.

Symptoms commonly include (but are not limited to):

All of these symptoms may also be caused by other factors, and are not necessarily due to air quality problems. For example, environmental stressors such as improper lighting, noise, vibration, and overcrowding, or problems such as emotional stress, can produce symptoms that are similar to those associated with poor indoor air quality.

Because people are different, one individual may react to an air quality problem while others have no noticeable ill effects. In other cases, complaints may be widespread. In addition to different degrees of reaction, an indoor air pollutant or problem can trigger different types of reactions in different people.

Children are especially susceptible to air pollutants like mercury. Others who may be more susceptible to effects of indoor air contaminants include people with asthma or allergies; people with respiratory disease; people whose immune systems are suppressed due to chemotherapy or disease; and contact lens wearers.

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What causes indoor air quality problems?

Over the past few decades, exposure to indoor air pollutants has increased due to a variety of factors, including the construction of more tightly sealed buildings that reduce fresh air exchange to save energy, the use of synthetic building materials and furnishings, and the use of chemically-formulated personal care products, pesticides, and housekeeping and teaching supplies.

Four basic factors affect indoor air quality. These include sources of pollutants; air pressure [the heating, ventilation, and air-conditioning (HVAC) system]; pollutant pathways; and people.

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How does the school’s ventilation system affect indoor air quality?

The HVAC system includes all heating, cooling, and ventilating equipment serving a school. Ideally, a properly designed and functioning HVAC system controls temperature and humidity to provide thermal comfort, distributes adequate amounts of outdoor air to meet ventilation needs of school occupants, and isolates and removes many pollutants through pressure control, filtration, and exhaust fans.

Not all HVAC systems are designed to do all of these things. Some buildings rely on natural ventilation, such as windows and normal air leaks in the buildings. Others lack cooling or have little or no humidity control.

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How can schools control indoor air quality?

There are some basic methods for lowering concentrations of indoor air pollutants. (All of these methods are described more fully in EPA’s Indoor Air Quality Tools for Schools Kit.)

The best way to prevent indoor air problems is to keep unnecessary pollutants out of the school building.

For example:

Ventilation helps remove pollutants and uses “cleaner” outdoor air to dilute the stale or used indoor air that people are breathing. Some building codes specify the amount of outdoor air that must be continuously supplied to an occupied area.

When painting, or in the event of a chemical spill, temporarily increasing the ventilation can be useful in diluting the concentration of fumes in the air. However, in a potentially high risk situation like a mercury spill on carpeting, care should be given to isolate the room. This means air from the contaminated room should not be allowed to enter other areas of the school through the HVAC system.

Another way to control exposure to indoor air pollutants is by separating the people from the pollutants. For example, stripping and waxing floors on Friday after school, so that the floor products have a chance to release vapors or gases over the weekend, thereby reducing the level of odors or contaminants in the air when students and staff return. Vacating a classroom while it is under renovation is another example. For more information, see our Renovation in Schools Fact Sheet.

Education of the school occupants is critical. If school staff are provided information about the sources and effects of contaminants, and about the proper operation of the ventilation system, they will better understand their indoor environment and can act to reduce exposure.

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How do I know if there is an air quality problem in my school?

Determining whether air quality is a problem in your school can be quite difficult. Health effects that suggest air quality problems are often similar to those from colds, allergies, fatigue, or the flu. There are clues, however, that may serve as indicators of potential indoor air problems:

Lack of symptoms does not mean that the quality of the air in the school is totally acceptable. For example, symptoms from long-term health effects (such as lung cancer due to radon ) often do not become evident for many years. For this reason, schools should establish a preventive indoor air program to minimize exposure of students and staff to indoor air pollutants.

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What can be done if there is an air quality problem at school?

If students or staff are experiencing symptoms that you believe may be related to their school environment, contact your school air quality or health and safety coordinator.

Whether or not the school has a known problem, encourage the school to develop and use an air quality management plan such as the one described in the EPA’s Indoor Air Quality Tools for Schools Kit. Using such a plan will likely prevent or fix many air quality problems. Some situations may dictate screening or testing by an outside consultant or engineer.

The Department of Health does provide information about school indoor air quality issues, but does not regulate indoor air quality in schools (with the exception of Vermont’s smoking laws and occupational standards, which were not created specifically for schools and do not address the specific needs of children).

In certain cases, such as a mercury spill, where there is a clear and imminent health threat, the health commissioner does have the authority to order improvements. If a major mercury spill occurs, the school should contact the Vermont Department of Health immediately. (See our Air Quality Fact Sheet on Mercury )

Where can I get more information?

More information on indoor air quality and school renovation is available at the U.S. Environmental Projection Agency’s Indoor Air Quality Tools for Schools website. For other contacts, see our Indoor Air Quality Resource Guide. Also see our Act 125 School Environmental Health website.

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