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Frequently Asked Questions about Improved Academic Performance

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Why is the Physical Environment of a School So Important?

A healthy school environment is one of the keys to keeping young minds and bodies strong. In fact, a healthy school environment is one of eight core components in the Centers for Disease Control and Prevention, or CDC, model “Healthy Youth! Coordinated School Health Program".

Factors that influence the physical environment include:

  • The school building and its surrounding area.
  • Any biological or chemical agent that is detrimental to health.
  • Physical conditions, such as temperature, noise and lighting.

Environmental factors in schools can cause serious health problems for children.

Poor maintenance of school environments can cause or intensify illnesses among children and their teachers, resulting in higher rates of absenteeism, less time in the classroom and ultimately, reduced academic achievement. But programs that promote healthy indoor air quality, or IAQ, can:

  • Improve health
  • Increase students’ ability to learn
  • Improve test scores
  • and improve adult productivity in the school system

Maintaining physical conditions and good environmental quality in schools can yield a high rate of return on academic outcomes.

The price of neglect is high, but the investment in maintenance need not be.

School districts can integrate no-cost and low-cost activities that safeguard the school environment and achieve significant health and performance improvements. School districts with proactive facility maintenance programs have demonstrated a strong business case for coordinating activities to improve the physical environment, as well as student health, in an integrated program focused on improved academic achievement.

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What Environmental Factors Are Important and Practical to Address?

School districts face tough choices in deciding how to allocate resources. However, funds invested in facility maintenance to prevent and fix problems that impact health and learning are both sound and necessary. So, how should schools invest their money?

The U.S. Environmental Protection Agency’s Indoor Air Quality Tools for Schools Program was launched in 1995 to help school districts effectively manage IAQ and improve the health and academic performance of students. Since its inception, thousands of school systems have adopted IAQ management plans based on IAQ Tools for Schools guidance.

In 2007, EPA conducted an in-depth evaluation of three school districts that had implemented IAQ Tools for Schools management programs to identify the programs’ impacts and the key drivers of improved outcomes. Before the programs were implemented, common IAQ challenges at all three sites included:

  • HVAC system problems
  • Cleanliness issues
  • Unsafe storage of chemicals and chemical-based products
  • Signs of dampness and mold
  • and pest management and food storage issues

After program implementation, all three cases showed positive IAQ outcomes resulting from:

  • Improved policies for HVAC maintenance
  • Cleaning
  • Use of smooth flooring (e.g., tile) rather than carpet
  • Construction and renovation management
  • and plant and animal policies

The weight of the scientific research combined with this field experience suggests that effective IAQ management plans will focus on the following:

Maintain the HVAC System

Maintenance and control of the HVAC system is perhaps the most critical component of any school district IAQ strategy designed to improve health and academic performance. Features of the HVAC system most associated with health and learning include:

  • Compliance with American Society of Heating, Refrigerating and Air-Conditioning Engineers, or ASHRAE, outdoor air ventilation standards in every occupied space.
  • Uniform temperature and humidity conditions that are within comfort standards with lower rather than higher temperatures preferred.
  • Regularly changed medium efficiency (MERV of 5-13) filters.
  • Clean and freely draining drain pans.
  • Dry insulation.
  • No major contaminant sources near any intake vent openings.

In addition to improving occupant health and performance, regular HVAC maintenance saves energy. Experience with ENERGYSTAR® qualified buildings demonstrates that well-maintained HVAC systems of average efficiency save more energy than high-efficiency HVAC systems that are poorly maintained. Well-maintained systems reduce energy use by an average of 15 to 20 percent.

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Control Moisture to Avoid Dampness and Mold

Dampness and mold are closely linked to respiratory illnesses. Controlling sources of moisture — such as leaky roofs and pipes and cracked foundations — prevents further building damage and saves on major repairs and replacement costs in the long term. Replacing stained ceiling tiles, cleaning spills within 24 to 48 hours and thoroughly drying damp or freshly cleaned carpets help prevent mold and mildew.

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Clean Thoroughly and Control Allergen Sources

A rigorous cleaning program helps maintain an environment conducive to health and learning. Schools should:

  • Follow good cleaning protocols
  • Choose low-toxicity cleaners
  • Avoid aerosol sprays
  • and establish measurable cleaning standards

Areas of focus include floors, surfaces and restrooms. Some districts have chosen smooth surface flooring to improve the ability to clean. Surface dust, particularly dust containing gram-negative bacteria or allergens, affects occupant health and performance. A large percentage of dust, including allergens, comes from outside the school. Cat allergens for example, may come in on clothing, while tree or grass pollen may enter through open doors or windows. In addition to a robust cleaning regimen, it is important to control animal allergens from classroom pets or pest allergens by using an integrated pest management program. Disinfecting frequently touched surfaces and encouraging proper hand-washing also helps prevent the spread of infectious agents.

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Select Products and Materials with Low Emissions

Growing interest in green buildings has stimulated the emergence of new programs to test and certify product and material emissions for IAQ. The Collaborative for High Performance Schools (CHPS) Exit program along with programs recognized by CHPS as comparable are the best current resource for school districts to reference when considering materials selection.

The certification criteria employ concentration limits for chronic health impacts, but protocols for evaluating acute health impacts have yet to be developed. Acute exposures are particularly important for wet products, such as paints and adhesives, so in addition to meeting the CHPS criteria, wet products that also satisfy Green Seal Exit certification criteria could offer added protection.

Cleaning products can be a significant source of contamination indoors because of their frequent use. Indeed, emissions from cleaning and maintenance of building materials and furnishings can far exceed those of the material itself over its life cycle. The Janitorial Products Pollution Prevention Project provides a useful resource for evaluating the toxicity of cleaning products, see Pollution Prevention. Exit

Recent research demonstrates that many cleaning products, including those labeled as “green,” contain chemicals that readily react with ozone in the air to produce secondary emissions from chemical reactions that may be far more harmful than the primary emissions from the product itself. School districts should note that cleaning products and air fresheners containing terpenes — also known as essential oils — are particularly prone to this phenomenon.

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Control Pests Using an Integrated Pest Management Program

Pesticides kill living organisms, such as:

  • Rodents
  • Cockroaches
  • Flying insects
  • and ants

As such, pesticides are harmful to humans, especially to children, and their use should be minimized. An Integrated Pest Management, or IPM, program controls pest populations primarily by minimizing pest entry into the school and removing their sources of food, water and shelter, while avoiding the use of harmful pesticides. When these measures are not sufficient, glues and traps are used when possible, while the careful and judicious application of pesticides is used as a last resort. With an IPM approach, pesticides are chosen to minimize toxicity impacts on occupants and are applied only where needed and only in the amount needed to reduce the pest population below predetermined action thresholds. Besides keeping the school clean, IPM maintenance practices include:

  • Storing trash in tight containers
  • Sealing cracks in walls or along the foundation
  • Sealing openings for pipes and electrical wiring
  • Fixing leaks
  • Removing standing water
  • Installing wire mesh on vents and floor drains, and screens on open window areas
  • and using good sanitation practices in food preparation and eating areas

Students and staff can participate in the program by removing leftover food and clutter from:

  • Lockers
  • Desks
  • Classrooms
  • and lounge areas

keeping their pet habitats clean and storing their food in tight containers. School districts that apply the IPM approach do not allow students and staff to bring pesticides into the school. EPA’s pesticides Website provides additional information on IPM programs, including how to get started, see Protecting Children in Schools from Pests and Pesticides

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Source Control

In the school environment, a broad range of indoor air pollutants — including radon, allergens and particulates such as from diesel exhaust and environmental tobacco smoke — adversely affect children’s health. To minimize the harmful effects of indoor air pollutants, it is important to determine and control their sources. Usually the most effective ways to improve IAQ are to eliminate or replace individual sources of pollution, reduce emissions, or place a barrier around the source so fewer pollutants are released into indoor air. Some approaches to source control include:

  • Testing for the presence of radon
  • Prohibiting school buses from idling near the school
  • Enforcing no-smoking policies
  • Avoiding the placement of garbage in rooms with HVAC equipment
  • and replacing moldy materials

Construction activities also can generate heavy pollution loads in occupied areas. During construction, schools can manage potential source problems by isolating the construction zone using physical barriers and exhaust fans; sealing HVAC intake ports from the construction contaminants and monitoring results to ensure that all specifications are met. In many cases, source control is a more cost-effective approach to protecting IAQ than increasing ventilation because increasing ventilation can increase energy costs.

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What Actions Have Real School Districts Taken and What Results Have They Seen?

School districts that are achieving outstanding results are incorporating the core elements of the EPA’s “Framework for Effective School IAQ Management” in their environmental, health and safety programs. The “Framework” synthesizes years of research into what makes the most successful IAQ management programs work and it distills that learning into a simple system that any school can adapt to meet its IAQ management needs. The “Framework” consists of six key drivers that describe the system for program success.

Real Examples of Successful Comprehensive IAQ Management in Schools

EPA has developed the “Envisioning Excellence” suite of materials and the “Framework” to help schools take effective action to advance health, safety and wellness initiatives. “Envisioning Excellence” tells the stories of several different school districts that applied the “Framework” to create effective and enduring IAQ programs. In their diversity, these stories demonstrate the feasibility and adaptability of the “Framework.” They make clear that any school, regardless of location, size, budget or facility conditions, can use the “Framework” to launch and sustain a successful IAQ program.

Visit the Case Studies page to learn about the school districts that have implemented the IAQ Tools for Schools guidance successfully.

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How Much Improvement Can You Expect in Academic Performance and Health?

No two school districts are alike. Each has its own set of maintenance challenges and repair needs. Yet studies and field experiences demonstrate that maintenance and repair programs designed to improve the school environment and reduce asthma exacerbations at school are likely to improve health, reduce absenteeism and enhance academic performance.

Basic Maintenance and School Conditions

Increased Average Daily Attendance (ADA) and Reduced Dropout Rate

Schools without a major maintenance backlog have a higher average daily attendance (ADA) by an average of 4 to 5 students per 1,000 and a lower annual dropout rate by 10 to 13 students per 1,000.6

  • Adding custodian/maintenance workers — and reducing the square footage each worker must maintain by an average of 1,000 square feet — increases ADA by 1 student per 1,000 and reduces the dropout rate by 4 students per 1,000. Eliminating the maintenance backlog and providing an annual maintenance budget that keeps the backlog at a minimum can increase ADA rates by an average of 4 to 5 students per 1,000 and reduce the annual dropout rate by 10 to 13 students per 1,000.6 Included in this study were repair needs of the:
    • Roof
    • Floor
    • Broken glass
    • and electrical system

Maintenance Improves Test Scores

  • Test scores uniformly increase as building conditions improve. Test scores can increase by 3 percent to 17 percent.55, 9, 12, 24 Specific results depend on the type of test and the degree of difference in building condition.

HVAC Maintenance Reduces Student Illness

  • HVAC maintenance that ensures:
    • Effective drain pan drainage,
    • Reduces excess moisture,
    • Avoids moist insulation,
    • and eliminates pollutant sources within the HVAC system or within 25 feet of the outside air intakes
    has been shown to reduce the incidence of lower respiratory symptoms:
    • Shortness of breath,
    • Cough,
    • Chest tightness and
    • Wheezing
    by up to 60 percent in adult populations.32, 59

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Outdoor Air Ventilation Rate

Higher Outdoor Air Ventilation Rates Increase Average Daily Attendance and Improve Student Performance

Children in classrooms with higher outdoor air ventilation rates tend to achieve higher scores on standardized tests in math and reading than children in poorly ventilated classrooms.57

  • Raising classroom outdoor air ventilation rates can reduce absenteeism by approximately five to 10 absences per 1,000 students for a 1,000 parts per million, or ppm, decrease in the difference between indoor and outdoor carbon dioxide (CO2) levels.58 For example, schools with classroom CO2 levels at approximately 1,500 ppm above outdoor CO2 levels (corresponding to a ventilation rate of about 7 cfm/person at steady state), where there are 50 absences per 1,000 students on average, may expect to reduce absentee rates to 40 or 45 absences per 1,000 students by raising ventilation rates so that classroom CO2 levels decrease to approximately 500 ppm above outdoor CO2 levels (corresponding to a ventilation rate of about 20 cfm per person).

    Classrooms with low outdoor air ventilation rates (e.g., about 7 cfm per person) could experience an improvement in school work performance (speed of school work tasks) of about 8 percent by doubling ventilation rates to the standards set by ASHRAE (about 13 to 15 cfm per person, based on typical design assumptions). Similarly, doubling low classroom ventilation rates could improve standardized test scores by about 10 percent.

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Dampness and Mold

Moisture and Mold Control Reduces Respiratory Illness and Absenteeism

  • Dampness and mold have been determined to be associated with 30 percent to 50 percent increases in a variety of respiratory and asthma-related health outcomes in homes. A comprehensive program to prevent dampness and mold (e.g., provide effective roof, wall and foundation drainage systems; prevent moisture intrusion through the building envelope and control condensation) could reduce the rates of respiratory illnesses associated with school environments.17, 38

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Rigorous Cleaning Reduces Health Symptoms, Complaints and Illness

  • Frequent and rigorous cleaning that removes surface particles, including allergens, could significantly reduce a variety of health symptoms and complaints.64, 63, 26, 48 A strong cleaning program can improve student and staff health in other ways as well. Disinfection of bathroom surfaces, combined with dispensers for alcohol-based hand rubs, can reduce absences from gastrointestinal infections by 10 percent to 15 percent.52

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