Making the Grade in Indoor Air Quality

Indoor air quality and its effects regarding the health, comfort, and well-being of students and teachers contribute significantly to learning and productivity in the classroom, and consequently, to academic performance and achievement. Since children spend most of their time in schools, daycare facilities, or at home, it is important to reduce their exposure to environmental pollutants as much as possible. Statistics show children receive the majority of their chemical exposure indoors — in these environments.

According to the U.S. Environmental Protection Agency (USEPA), 20 percent of the U.S. population spends most of their time in more than 120,000 public and private schools. Many of the school buildings are old and in poor condition, and the state of their indoor environments often inhibit learning and pose elevated health risks for children and teachers. The USEPA estimates that half of U.S. schools have indoor air quality problems. Children are at greater risk to develop health problems due to poor indoor air quality because they are more susceptible to pollutants than adults, and they spent the majority of their time in school or daycare facilities. Their organs and respiratory, immune, and neurological systems are still developing, and because of their lower body weight and fast breathing rate, they receive a higher pollutant dose per body weight than adults. Newborns breathe through their mouths, as do many older infants and children — more so than adults. This difference in breathing may increase children’s risk of pulmonary exposure to particulates and fibers, which would otherwise be filtered out in the nose. Also, children’s breathing zones are much closer to the ground than adults’, and as a result, heavier airborne chemicals and settled dust pose a greater risk to children than to adults. These factors combine to create a higher body burden of air pollutants for the same amount of exposure.

Health problems that may result from poor indoor air quality in schools include headaches; nasal congestion; breathing problems; eyes, nose, and throat irritation; coughing; rashes; and many other problems depending on the type of chemical. Molds and allergens can lead to respiratory illnesses, and can trigger allergy or asthma attacks and worsen allergy and asthma symptoms. Environmental asthma triggers commonly found in school buildings are cockroaches and other pests, mold resulting from excess moisture in the building, animal dander, and dust mites. Children suffering from asthma may also be affected by other pollutants found in schools, including volatile organic compounds (VOCs) emitting from sources such as cleaning agents, dry-erase markers, furnishings, building materials, and personal hygiene products.

Toys, furniture, paint, flooring, mattresses, cleaners, electronics, and all items in the indoor space can release chemicals that pollute the indoor environment, where children spend 85 to 90 percent of their time. Some chemicals known as VOCs become airborne, and children can easily breathe them in. Many have irritating odors, while others cannot be physically observed. Other heavier VOCs and metals become attached to small dust particles that can also become airborne and penetrate the lungs as children breathe. In most cases, these pollutants are two, or as much as 100, times higher indoors than found in the outside air. These statistics are important because exposure to these chemicals can have short- and long-term health consequences.

Regarding indoor air quality, schools have unique characteristics that make them more of a concern than other types of buildings. A typical school can have four times as many occupants as an office building for the same amount of floor space, leading to much greater occupant density. New classrooms may be built, or classrooms may be divided without considering the ventilation system. On top of that, most schools, whether public or private, are usually strapped for funds, which means there is often little money available for adequate system maintenance. Additionally, many different types of activities in schools may contribute pollutants to the indoor air; for example, science labs, art classes, and vocational classrooms such as auto shops, photography, and woodshops.

Creating and maintaining good indoor environments through preventative, ongoing indoor air quality management and rigorous source control is of utmost importance in schools and daycare facilities. A multitude of resources and tools are available to school administrators, buyers, and facility professionals to achieve acceptable indoor pollutant levels in their facilities, among them the USEPA’s “Tools for Schools” program (, the Collaborative for High Performance Schools (, and, of course, GREENGUARD Children & Schools Certification and its online resources (

Henning Bloech is the executive director of the GREENGUARD Environmental Institute.