Reference Guide for Indoor Air Quality in Schools
This common-sense guidance is designed to help you prevent and solve the majority of indoor air problems with minimal cost and involvement
Understanding the importance of good indoor air quality (IAQ) in schools is the backbone of developing an effective IAQ program. Poor IAQ can lead to a large variety of health problems and potentially affect comfort, concentration and staff/student performance. In recognition of tight school budgets, this guidance is designed to present practical and often low-cost actions you can take to identify and address existing or potential air quality problems. You can accomplish this using current school staff to perform a limited and well-defined set of basic operations and maintenance activities. However, some actions may require specialized expertise.
Section 1 and Section 2 of this Guide help schools understand how IAQ problems develop, the importance of good IAQ and its impact on students, staff and building occupants. The next step, which is outlined in Section 3, is communicating this important information with:
- and the community
Schools dealing with an IAQ crisis will find the section on communication particularly helpful. Section 4, Section 5 and Section 6 contain valuable information for schools that need assistance diagnosing and responding to IAQ problems with inexpensive, practical solutions.
Refer to the appendices of this Guide for detailed information on IAQ-related topics including:
- Secondhand smoke
- and portable classrooms
Schools may find the explanations of integrated pest management programs, typical indoor air pollutants and pollutants from motor vehicles and equipment helpful while developing school policies or pinpointing sources of poor IAQ. In addition, schools investigating or resolving IAQ problems may want to refer to appendices on basic measurement equipment, hiring professional assistance and codes and regulations. There are numerous resources available to schools through EPA and other organizations, many of which are listed in Appendix L. Use the information in this Guide to create the best possible learning environment for students and maintain a comfortable, healthy building for school occupants. See Appendix L
Section 1 - Why IAQ Is Important to Your School
Most people are aware that outdoor air pollution can impact their health, but indoor air pollution can also have significant and harmful health effects. The U.S. Environmental Protection Agency (EPA) studies of human exposure to air pollutants indicate that indoor levels of pollutants may be two to five times — and occasionally more than 100 times — higher than outdoor levels. These levels of indoor air pollutants are of particular concern because most people spend about 90 percent of their time indoors. For the purposes of this guidance, the definition of good indoor air quality (IAQ) management includes:
- Control of airborne pollutants;
- Introduction and distribution of adequate outdoor air; and
- Maintenance of acceptable temperature and relative humidity.
Good IAQ contributes to a favorable environment for students, performance of teachers and staff and a sense of comfort, health and well-being. These elements combine to assist a school in its core mission — educating children.
Temperature and humidity cannot be overlooked because thermal comfort concerns underlie many complaints about "poor air quality." Furthermore, temperature and humidity are among the many factors that affect indoor contaminant levels.
Outdoor sources should also be considered since outdoor air enters school buildings through windows, doors and ventilation systems. Thus, transportation and grounds maintenance activities become factors that affect indoor pollutant levels as well as outdoor air quality on school grounds.
Why Is IAQ Important?
In recent years, comparative risk studies performed by EPA and its Science Advisory Board (SAB) have consistently ranked indoor air pollution among the top five environmental risks to public health. Good IAQ is an important component of a healthy indoor environment, and can help schools reach their primary goal of educating children.
Failure to prevent or respond promptly to IAQ problems can:
- Increase long- and short-term health problems for students and staff such as:
- Eye irritation
- Allergic reactions, and
- in rarer cases, life-threatening conditions such as Legionnaire’s disease, or carbon monoxide poisoning
- Aggravate asthma and other respiratory illnesses. Nearly 1 in 13 children of school-age has asthma, the leading cause of school absenteeism due to chronic illness. There is substantial evidence that indoor environmental exposure to allergens, such as dust mites, pests and molds, plays a role in triggering asthma symptoms. These allergens are common in schools. There is also evidence that exposure to diesel exhaust from school buses and other vehicles exacerbates asthma and allergies. These problems can:
- Impact student attendance, comfort and performance.
- Reduce teacher and staff performance.
- Accelerate the deterioration and reduce the efficiency of the school’s physical plant and equipment.
- Increase potential for school closings or relocation of occupants.
- Strain relationships among school administration, parents and staff.
- Create negative publicity.
- Impact community trust.
- Create liability problems.
Indoor air problems can be subtle and do not always produce easily recognized impacts on health, well-being, or the physical plant. Symptoms, such as:
- Shortness of breath
- Sinus congestion
- and irritation of the
- and skin
are not necessarily due to air quality deficiencies, but may also be caused by other factors—poor lighting, stress, noise and more. Due to varying sensitivities among school occupants, IAQ problems may affect a group of people or just one individual. In addition, IAQ problems may affect people in different ways.
Individuals that may be particularly susceptible to effects of indoor air contaminants include, but are not limited to, people with:
- Asthma, allergies, or chemical sensitivities;
- Respiratory diseases;
- Suppressed immune systems (due to radiation, chemotherapy, or disease); and
- Contact lenses.
Certain groups of people may be particularly vulnerable to exposures of certain pollutants or pollutant mixtures. For example:
- People with heart disease may be more adversely affected by exposure to carbon monoxide than healthy individuals.
- People exposed to significant levels of nitrogen dioxide are at higher risk for respiratory infections.
In addition, the developing bodies of children might be more susceptible to environmental exposures than those of adults. Children breathe more air, eat more food and drink more liquid in proportion to their body weight than adults. Therefore, air quality in schools is of particular concern. Proper maintenance of indoor air is more than a "quality" issue; it encompasses safety and stewardship of your investment in students, staff and facilities.
Unique Aspects of Schools
Unlike other buildings, managing schools involves the combined responsibility for public funds and child safety issues. These can instigate strong reactions from concerned parents and the general community. Many other aspects are unique to schools:
- Occupants are close together, with the typical school having approximately four times as many occupants as office buildings for the same amount of floor space.
- Budgets are tight, with maintenance often receiving the largest cut during budget reductions.
- The presence of a variety of pollutant sources, including:
- Art and science supplies
- Industrial and vocational arts
- Home economic classes
- and gyms
- A large number of heating, ventilating and air-conditioning equipment place an added strain on maintenance staff.
- Concentrated diesel exhaust exposure due to school buses. (Students, staff and vehicles congregate at the same places at the same time of day, increasing exposure to vehicle emissions.) Long, daily school bus rides may contribute to elevated exposure to diesel exhaust for many students.
- As schools add space, the operation and maintenance of each addition are often different.
- Schools sometimes use rooms, portable classrooms, or buildings that were not originally designed to service the unique requirements of schools.
For more information, see Indoor Air Quality.
Section 2 - Understanding IAQ Problems
Over the past several decades, exposure to indoor air pollutants has increased due to a variety of factors. These include:
- The construction of more tightly sealed buildings
- Reduced ventilation rates to save energy
- The use of synthetic building materials and furnishings
- The use of personal care products, pesticides and housekeeping supplies
- and the increased use of vehicles and power equipment
In addition, activities and decisions, such as deferring maintenance to "save" money, can lead to problems from sources and ventilation.
The indoor environment in any building is a result of the interactions among:
- The site
- Building structure
- Mechanical systems (as originally designed and later modified)
- Construction techniques
- Contaminant sources
- Building occupants
- and outdoor mobile sources
- and grounds maintenance equipment
This section contains a discussion on how these elements can cause IAQ problems, and Section 6 provides solutions. See Section 6: "Solving IAQ Problems"
These elements are grouped into four categories:
- Sources of Indoor Air Pollution
- HVAC System Design and Operation
- Pollutant Pathways and Driving Forces
- Building Occupants
Sources of Indoor Air Pollutants
Interaction of Sources, HVAC Systems, Pathways and Occupants
If independently evaluated, a minor roof leak and a dirty classroom carpet might not cause much concern. But if the water from the roof leak reaches the carpet, the water can wet the dirt in the carpet and the mold that has been dormant in the carpet. The mold can grow and become a pollutant source that releases spores into the classroom air. The HVAC system may act as a pathway that disperses the spores to other parts of the school, where occupants may experience allergic reactions.
Indoor air pollutants can originate within the building or be drawn in from outdoors. Air contaminants consist of numerous
- and gases
It is important to control air pollutant sources, or IAQ problems can arise — even if the HVAC system is properly operating. It may be helpful to think of air pollutant sources as fitting into one of the categories in the following table, "Typical Sources of Indoor Air Pollutants". The examples given for each category are not intended to be an exhaustive list. Appendix E: "Typical Indoor Air Pollutants" contains a list of specific air pollutants with descriptions, sources and control measures. See:
In addition to the number of potential pollutants, another complicating factor is that indoor air pollutant concentration levels can vary by time and location within the school building, or even a single classroom. Pollutants can be emitted from a variety of sources including:
- Point sources (such as from science storerooms);
- Area sources (such as newly painted surfaces); and
- Mobile sources (such as cars, buses and power equipment).
Pollutants can also vary with time since some activities take place over a short period of time (such as stripping floors) or occur continuously (such as mold growing in the HVAC system).
Indoor air often contains a variety of contaminants at concentrations that are well below the published occupational standards. Given our present knowledge, it is often difficult to relate specific health effects to exposures to specific pollutant concentrations, especially since the significant exposures may be due to low levels of pollutant mixtures.
Typical Sources of Indoor Air Pollutants
|Polluted Outdoor Air
HVAC System Design and Operation
The HVAC system includes all heating, cooling and ventilating equipment serving a school:
- Boilers or furnaces
- Cooling towers
- Air-handling units
- Exhaust fans
- and filters
Properly designed HVAC equipment in a school helps to:
- Control temperature and relative humidity to provide thermal comfort;
- Distribute adequate amounts of outdoor air to meet ventilation needs of school occupants; and
- Isolate and remove odors and other contaminants through pressure control, filtration and exhaust fans.
Not all HVAC systems accomplish all of these functions. Some buildings rely only on natural ventilation. Others lack mechanical cooling equipment, and many function with little or no humidity control. The features of the HVAC system in a given building will depend on:
- Age of the design;
- Building codes in effect at the time of the design;
- Budget for the project;
- Designers’ and school districts’ individual preferences;
- Subsequent modifications;
- Space type; and
- Expected occupancy.
Description of HVAC Systems
The two most common HVAC designs in schools are unit ventilators and central air-handling systems. Both can perform the same HVAC functions, but a unit ventilator serves a single room while the central air-handling unit serves multiple rooms. For basic central air-handling units, it is important that all rooms served by the central unit have similar thermal and ventilation requirements. If these requirements differ significantly, some rooms may be too hot, too cold, or under ventilated, while others are comfortable and adequately ventilated.
Most air-handling units distribute a mixture of outdoor air and recirculated indoor air. HVAC designs may also include units that introduce 100 percent outdoor air or that simply recirculate indoor air within the building. Uncontrolled quantities of outdoor air enter buildings by leakage through windows, doors and gaps in the building exterior. Thermal comfort and ventilation needs are met by supplying "conditioned" air, which is a mixture of outdoor and recirculated air that has been filtered, heated or cooled and sometimes humidified or dehumidified. The basic components for a central air handling unit and a unit ventilator are illustrated in the IAQ Backgrounder.
All schools need ventilation, which is the process of supplying outdoor air to occupied areas within the school.
A number of variables interact to determine whether people are comfortable with the temperature and relative humidity of the indoor air. Factors such as:
- Activity level
- and physiology of people in schools
vary widely, so the thermal comfort requirements vary for each individual. The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 55-1992 (summarized in the table below) describes the temperature and humidity ranges that are comfortable for 80 percent of people engaged in largely sedentary activities. The ASHRAE standard assumes "normal indoor clothing." Added layers of clothing reduce the rate of heat loss.
Recommended Ranges of Temperature and Relative Humidity
|Relative Humidity||Winter Temperature||Summer Temperature|
|30%||68.5oF - 75.5oF||74.0oF - 80.0oF|
|40%||68.0oF - 75.0oF||73.5oF - 80.0oF|
|50%||68.0oF - 74.5oF||73.0oF - 79.0oF|
|60%||67.5oF - 74.0oF||73.0oF - 78.5oF|
Recommendations apply for persons clothed in typical summer and winter clothing, at light, mainly sedentary, activity. Source: Adopted from ASHRAE Standard 55-1992, Thermal Environmental Conditions for Human Occupancy
Uniformity of temperature is important to comfort. Rooms that share a common heating and cooling system controlled by a single thermostat may be at different temperatures. Temperature stratification is a common problem caused by convection—the tendency of light, warm air to rise, and heavier, cooler air to sink. If air is not properly mixed by the ventilation system, the temperature near the ceiling can be several degrees warmer or cooler than near the floor, where young children spend much of their time. Even if air is properly mixed, uninsulated floors over unheated spaces can create discomfort in some climate zones. Large fluctuations of indoor temperature can also occur when thermostats have a wide "dead band" (a temperature range in which neither heating or cooling takes place).
Radiant heat transfer may cause people located near very hot or very cold surfaces to be uncomfortable even though the thermostat setting and the measured air temperature are within the comfort range. Schools with large window areas sometimes have acute problems of discomfort due to radiant heat gains and losses, with the locations of complaints shifting during the day as the sun angle changes. Poorly insulated walls can also produce a flow of naturally-convecting air, leading to complaints of draftiness.
Closing curtains reduces heating from direct sunlight and reduces occupant exposure to hot or cold window surfaces. Large schools may have interior ("core") spaces in which year-round cooling is required to compensate for heat generated by occupants, office equipment and lighting, while perimeter rooms may require heating or cooling depending on outdoor conditions.
Humidity is a factor in thermal comfort. Raising relative humidity reduces a person’s ability to lose heat through perspiration and evaporation, so that the effect is similar to raising the temperature. Humidity extremes can also create other IAQ problems. Excessively high or low relative humidity can produce discomfort, high relative humidity can promote the growth of mold and mildew, and low relative humidity can accelerate the release of spores into the air. See Appendix H: "Mold and Moisture".
Ventilation For Occupant Needs
Ventilation is the process of supplying outdoor air to the occupied areas in the school while indoor air is exhausted by fans or allowed to escape through openings, thus removing indoor air pollutants. Often, this exhaust air is taken from areas that produce air pollutants such as:
- Science-storage closets
- and fume hoods
Modern schools generally use mechanical ventilation systems to introduce outdoor air during occupied periods, but some schools use only natural ventilation or exhaust fans to remove odors and contaminants. In naturally ventilated buildings, unacceptable indoor air quality is particularly likely when occupants keep the windows closed due to extreme hot or cold outdoor temperatures. Even when windows and doors are open, inadequate ventilation is likely when air movement forces are weakest, such as when there is little wind or when there is little temperature difference between inside and outside (stack effect).
Stack effect is the pressure-driven airflow produced by convection, the tendency of warm air to rise. Stack effect exists whenever there is an indoor-outdoor temperature difference, and the effect becomes stronger as the temperature difference increases. Multi-story schools are more affected than single-story schools. As heated air escapes from upper levels, indoor air moves from lower to upper levels, and outdoor air is drawn into the lower levels to replace the air that has escaped. Stack effect can transport contaminants between floors by way of:
- Elevator shafts
- Utility chases
- and other openings
The amount of outdoor air considered adequate for proper ventilation has varied substantially over time. Because updating building codes often takes several years, current building codes may require more ventilation than when the system was designed. ASHRAE ventilation standards are used as the basis for most building ventilation codes. A table of outdoor air quantities in schools as recommended by ASHRAE Standard 62-2001, "Ventilation for Acceptable Indoor Air Quality," is shown below. Please note that this is a limited portion of the Standard, and that the quantities listed are in units of cfm per person, which are cubic feet per minute of outdoor air for each person in the area served by that ventilation system.
Selected Outdoor Air Ventilation Recommendations (minimum)
|Application||Cubic Feet per Minute (CFM)
|Spectator Sport Areas||15|
|Source: ASHRAE Standard 62-2001, Ventilation for Acceptable Indoor Air Quality|
Pollutant Pathways and Driving Forces
Airflow patterns in buildings result from the combined forces of mechanical ventilation systems, human activity and natural effects. Air pressure differences created by these forces move airborne pollutants from areas of higher pressure to areas of lower pressure through any available openings in:
- Building walls
- and HVAC systems
For example, as long as the opening to an inflated balloon is kept shut, no air will flow. When opened, however, air will move from inside (area of higher pressure) to the outside (area of lower pressure).
Even if the opening is small, air will move until the inside pressure is equal to the outside pressure. If present, the HVAC ducts are generally the predominant pathway and driving force for air movement in buildings. However, all of a building’s components,
- HVAC equipment
- and occupants
interact to affect how air movement distributes pollutants within a building.
As air moves from supply outlets to return inlets, for example, it is diverted or obstructed by walls and furnishings, and redirected by openings that provide pathways for air movement. On a localized basis, the movements of people have a major impact on pollutant transport. Some of the pathways change as doors and windows open and close. It is useful to think of the entire building — the rooms with connecting corridors and utility passageways between them — as part of the air-distribution system.
Air movement can transfer emissions from the pollutant source:
- Into adjacent rooms or spaces that are under lower pressure.
- Into other spaces through HVAC system ducts.
- From lower to upper levels in multi-story schools.
- Into the building through either infiltration of outdoor air or reentry of exhaust air.
- To various points within the room.
Natural forces exert an important influence on air movement between a school ’s interior and exterior. Both the stack effect and wind can overpower a building’s HVAC system and disrupt air circulation and ventilation, especially if the school envelope (walls, ceiling, windows, etc.) is leaky.
Wind effects are transient, creating local areas of high pressure (on the windward side) and low pressure (on the leeward side) of buildings. Depending on the size and location of leakage openings in the building exterior, wind can affect the pressure relationships within and between rooms. Entry of outdoor air contaminants may be intermittent or variable, occurring only when the wind blows from the direction of the pollutant source.
Most public and commercial buildings are designed to be positively pressurized, so that unconditioned air does not enter through openings in the building envelope causing discomfort or air quality problems. The interaction between pollutant pathways and intermittent or variable driving forces can lead to a single source causing IAQ complaints in an area of the school that is distant from the pollutant source.
It is important for occupants to understand how their activities directly affect ventilation pathways and sources of pollutants in their school.
Occupant activities can directly affect:
- Pollutant sources
- The HVAC system (operation, maintenance, controls)
- and driving forces
Occupants can also be carriers of communicable disease and allergens, such as pet dander. Teachers may use dry-erase markers or laboratory chemicals that emit pollutants. Similarly, many cleaning materials used in schools contain VOCs that can degrade IAQ.
Teachers and administrators often obstruct proper air movement in their classrooms and offices by using ventilation units as bookshelves, unknowingly restricting the pathway for fresh air to enter the area. Similarly, covering air return ducts (with posters, for example) restricts proper air circulation. Therefore, it is important for occupants to understand how their activities directly affect ventilation pathways and sources of pollutants in their school.
Occupants can contribute to a healthy indoor environment by completing the IAQ checklists, monitoring their own behavior and immediately alerting the IAQ Coordinator of any IAQ problems.
Section 3 - Effective Communication
Good communication can help to prevent IAQ problems and can allay unnecessary fears. In addition, schools should respond promptly and effectively to any IAQ issues that may arise. Communication can assist school occupants in understanding how their activities affect IAQ, which will enable the occupants to improve their indoor environment through proper choices and actions. For more information on communication strategies for addressing IAQ concerns see EPA's IAQ Tools for Schools Communications Guide[EPA 402-K-02-008].
The checklists, forms and information contained in this guide will assist you in accomplishing the first three objectives. In addition, refer to the list of communication principles below.
The necessary level of communication is often dependent on the severity of the IAQ complaint. If the complaint can be resolved quickly (e.g., an annoying but harmless odor from an easily identified source) and involves a small number of people, communication can be handled in a straightforward manner without risking confusion and bad feeling among school occupants. Communication becomes a more critical issue when there are delays in identifying and resolving the problem and when serious health concerns are involved.
The fourth objective deals with informing occupants and parents before the start of significant planned activities that produce odors or contaminants. If occupants and parents are uninformed, they may become concerned about unknown air contaminants, such as strange odors or excessive levels of dust, and register an IAQ complaint. Examples of planned activities include:
- Pest control
- and installation of new flooring
Notification of planned activities can also prevent problems from arising with students and staff with special needs. For example, an asthmatic student may wish to avoid certain areas within a school, or use alternative classrooms, during times when a major renovation project will produce higher levels of dust. A sample notification letter is provided in the model painting policy in Appendix B: "Developing Indoor Air Policies" in the IAQ Coordinator’s Guide: A Guide to Implementing an IAQ Program. See Appendix B
The fifth objective involves effective listening. School occupants can often provide information that helps prevent problems, and being "heard" may help defuse negative reactions by occupants if indoor air problems develop.
Schools and school districts can reap many benefits from taking a proactive approach to addressing IAQ issues. The positive public relations that can result from this approach can lead to a better understanding of IAQ by school occupants and the community. Communicating effectively — both internally and externally — is a key element.
Build rapport with the local media now. An informed media that is aware of your efforts to prevent IAQ problems and that understands the basics of IAQ in schools can be an asset instead of a liability during an IAQ crisis.
Communicating the goals of the IAQ Management Plan to those within the school,
- Support staff
- The school nurse
is key. The following steps can help develop good communication between you and the school occupants:
- Provide accurate information about factors that are affecting IAQ.
- Clarify the responsibilities and activities of the IAQ Coordinator.
- Clarify the responsibilities and activities of each occupant.
- Notify occupants and parents of planned activities that may affect IAQ.
- Employ good listening skills.
When an IAQ problem occurs, you can be assured that the school community will learn about it quickly. Without open communication, any IAQ problem can become complicated by anxiety, frustration and distrust. These complications can increase both the time and money needed to resolve the problem.
Immediate communication is vital, and is easiest if a few strategic steps are taken before an IAQ problem arises. First, ensure that a spokesperson is ready by having a working understanding of the communication guidance found in this section, and a background knowledge of IAQ as outlined in Section 1 and Section 2. This person should also have complete access to information as the investigation progresses. Because of these qualifications, the IAQ Coordinator may be a good choice for spokesperson. Second, establish a plan for how you will communicate to the school community. The school community includes:
- All occupants of the school
- The school district administration and school board
- The local union
- and the local news media
Paying attention to communication when solving a problem helps to ensure the support and cooperation of school occupants as the problem is investigated and resolved. There are basic, yet important, messages to convey:
- School administrators are committed to providing a healthy and safe school.
- Good IAQ is an essential component of a healthy indoor environment.
- IAQ complaints are taken seriously.
When a problem arises, communication should begin immediately. You should not wait until an investigation is nearly completed or until final data are available before providing some basic elements of information. Communications, whether in conversations or in writing, should include the following elements in a factual and concise manner:
- The general nature of the problem, the types of complaints that have been received and the locations that are affected;
- The administration’s policy in regard to providing a healthy and safe environment;
- What has been done to address the problems or complaints, including the types of information that are being gathered;
- What is currently being done, including factors that have been evaluated and found not to be causing or contributing to the problem;
- How the school community can help;
- Attempts that are being made to improve IAQ;
- Work that remains to be done and the expected schedule for its completion;
- The name and telephone number of the IAQ Coordinator, who can be contacted for further information or to register complaints; and
- When the school will provide the next update.
Productive relations will be enhanced if the school community is given basic progress reports during the process of diagnosing and solving problems. It is advisable to explain the nature of investigative activities, so that rumors and suspicions can be countered with factual information. Notices or memoranda can be posted in general use areas and delivered directly to:
- The school board
- The local union
- and other interested constituents of the school community
Newsletter articles, the school Web site, or other established communication channels can also be used to keep the school community up-to-date.
Problems can arise from saying either too little or too much. Premature release of information when data-gathering is still incomplete can cause confusion, frustration and future mistrust. Similar problems can result from incorrect representation of risk — improperly assuming the worst case or the best. However, if even simple progress reports are not given, people will think that either nothing is being done or that something terrible is happening.
Even after the problem is correctly diagnosed and a proper mitigation strategy is in place, it may take days or weeks for contaminants to dissipate and symptoms to disappear. If building occupants are informed that their symptoms may persist for some time after solving the problem, the inability to bring instant relief is less likely to be seen as a failure.
Remember to communicate as the final step in problem-solving — although you may know that the problem has been resolved, the school community may not know, so be sure to provide a summary status report. The graphic below summarizes the main steps for responsive communications.
- Be honest, frank and open. Once trust and credibility are lost, they are almost impossible to regain. If you don’t know an answer or are uncertain, say so. Admit mistakes. Get back to people with answers. Discuss data uncertainties, strengths and weaknesses.
- Respect your audience. Keep explanations simple, avoiding technical language and jargon as much as possible. Use concrete images that communicate on a personal level. People in the community are often more concerned about such issues as
- and compassion
- Employ your best listening skills. Take time to find out what people are thinking, rather than assuming that you already know.
- Tailor communication strategies to your audience. Use mass media for providing information, and interpersonal techniques for changing attitudes.
- Involve school employees. An informed staff is likely to be a supportive staff.
- Involve parents. Inform parents about what is being done and why, as well as what will happen if problems are detected.
- Involve the school board. Encourage board members to observe the process (e.g., taking a walk-through of the school with the IAQ Coordinator).
- Involve businesses that provide services to the school (e.g., exterminators, bus fleet administrators/operators) and businesses located around the school, which may also negatively impact IAQ.
- Emphasize action. Always try to include a discussion of actions that are underway or that can be taken.
- Encourage feedback. Accentuate the positive and learn from your mistakes.
- Strive for an informed public. The public should be:
- and collaborative
- Be prepared for questions. Provide background material on complex issues. Avoid public conflicts or disagreements among credible sources.
- Be responsive. Acknowledge the emotions that people express and respond in words and actions. When in doubt, lean toward sharing more information, not less, or people may think you are hiding something.
- Combat rumors with facts. For example, set up a chalkboard in the teachers’ lounge or in another general use area for recording what is heard. Record rumors as they arise and add responses. Then pass out copies to the staff.
- Do not over promise. Promise only what you can do and follow through with each promise.
- Work with the media. Be accessible to reporters and respect deadlines. Try to establish long-term relationships of trust with specific editors and reporters. Remember that the media are frequently more interested in politics than in science, more interested in simplicity than complexity and more interested in danger than safety.
Section 4 - Resolving IAQ Problems
Resolving IAQ problems involves diagnosing the cause, applying practical actions that either reduce emissions from pollutant sources, remove pollutants from the air (e.g., increasing ventilation or air cleaning), or both. Problems related to sources can stem from improper material selection or application, allowing conditions that can increase biological contamination and dust accumulation, or source location. Ventilation problems stem from:
- Improper design
- or maintenance of the ventilation system
This Guide provides information on most IAQ problems found in schools, and does not require that pollutant measurements be performed and analyzed. It is important to take reported IAQ problems seriously and respond quickly:
- IAQ problems can be a serious health threat and can cause acute discomfort (irritation) or asthma attacks.
- Addressing an IAQ problem promptly is good policy. Parents are sensitive to unnecessary delays in resolving problems that affect their children. Staff have enough burdens without experiencing frustration over unresolved problems, and unaddressed problems invariably lead to greater complaints.
- Diagnosing a problem is often easier immediately after the complaint(s) has been received. The source of the problem may be intermittent and the symptoms may come and go. Also, the complainant’s memory of events is best immediately after the problem occurs.
In some cases, people may believe that they are being adversely affected by the indoor air, but the basis for their perception may be some other form of stressor not directly related to IAQ. Section 6: "Solving IAQ problems," discusses some of these stressors such as glare, noise and stress. See Section 6.
Is This an Emergency?
The first decision that must be made in dealing with an IAQ problem is whether the problem requires an emergency response, as shown in the diagram below. Some IAQ incidents require immediate response — for example, high carbon monoxide levels or certain toxic chemical spills will require evacuation of all affected areas in the school, and biological contaminants such as Legionella may require a similar response. In recent years, large outbreaks of influenza have caused entire schools and districts to cease operation temporarily. Some schools and districts may already have established policies on what constitutes a life and safety emergency. Local and state health departments can also be helpful in defining life- and safety-threatening emergencies.
If this is an emergency situation, in addition to immediate action to protect life and health, it is vital that the school administration, parents of students and appropriate authorities be notified of the situation in a carefully coordinated manner. You must also be prepared to deal quickly and properly with questions from local media. Review the guidance in Section 3: "Effective Communication," and in EPA's IAQ Tools for Schools Communications Guide to assist in managing the issues of notification and communication. See:
Who Will Solve the Problem?
For most IAQ issues, schools can pull together a team of in-house staff to solve and prevent problems.
For most IAQ issues, schools can pull together a team of in-house staff with an appropriate range of skills to resolve and prevent problems. The IAQ Backgrounder and checklists provide information on typical IAQ problems found in schools. On the other hand, unique or complex IAQ problems may best be handled by professionals who have specialized knowledge, experience and equipment. Knowledge of your staff’s capabilities will help you decide whether to use in-house personnel or hire outside professionals to respond to a specific IAQ problem. See:
Regardless of whether it is in-house staff or outside assistance that diagnoses and resolves the problem, the IAQ Coordinator remains responsible for managing the problem-solving process and for communicating with all appropriate parties during the process. If an IAQ Coordinator has not been appointed already, please refer to Section 2: "Role and Functions of the IAQ Coordinator," in the IAQ Coordinator's Guide.
Section 5 - Diagnosing IAQ Problems
The goal of diagnosing an IAQ problem is to identify the cause of the problem and implement an appropriate solution. Often, more than one problem can exist, requiring more than one solution. For this reason, EPA created the Problem Solving Checklist (Appendix A: "IAQ Coordinator’s Forms" in the IAQ Coordinator’s Guide) and the IAQ Problem Solving Wheel (a separate tab of the Action Kit). For best results, it is also important to have good background knowledge of the basics of IAQ as outlined in Section 1 and Section 2. See:
The IAQ diagnostic process begins when a complaint is registered or an IAQ problem is discovered. Many problems can be simple to diagnose, requiring a basic knowledge of IAQ and some common sense. If the cause (or causes) of the IAQ problem has already been identified, proceed to the solution phase outlined in Section 6: "Solving IAQ problems."
Not all occupant complaints about IAQ are caused by poor indoor air. Other factors such as noise, lighting and job-, family-, or peer-related stress can — individually and in combination — contribute to a perception that IAQ is poor.
How to Diagnose Problems
The Problem Solving Checklist and the IAQ Problem Solving Wheel are your primary tools for finding solutions to problems. They will help simplify the process and lead the investigation in the right direction.
Start with the Problem Solving Checklist and encourage school staff to answer questions or perform activities posed by the checklist and the wheel. Pollutant sources and the ventilation system may act in combination to create an IAQ problem. Resolve as many problems as possible and note any problems that you intend to fix later.
Once you identify the likely cause of the IAQ problem, or the solution is readily apparent, refer to Section 6: "Solving IAQ Problems" for potential courses of action.
Spatial and Timing Patterns
As a first step, use the spatial pattern (locations) of complaints to define the complaint area. Focus on areas in the school where symptoms or discomfort have been reported. The complaint area may need to be revised as the investigation progresses. Pollutant pathways can cause complaints in parts of the school that are located far away from the source of the problems. See the tables below.
After defining a location (or group of locations), look for patterns in the timing of complaints. The timing of symptoms and complaints can indicate potential causes and provide directions for further investigation. Review the data for cyclic patterns of symptoms (e.g., worst during periods of minimum ventilation or when specific sources are most active) that may be related to the HVAC system or to other activities affecting IAQ in or near the school.
|SPATIAL PATTERNS OF COMPLAINTS||SUGGESTIONS|
|Widespread, no apparent spatial pattern||
|Localized (e.g., affecting individual rooms, zones, or air handling systems)||
|TIMING PATTERNS OF COMPLAINTS||SUGGESTIONS|
|Symptoms begin and/or are worst at the start of the occupied period||
|Symptoms worsen over the course of the occupied period.||
|Single occurrence of symptoms||
|Recent onset of symptoms||
|Symptoms relieved on leaving the school, either immediately, overnight, or (in some cases) after extended periods away from the building||
Section 6 - Solving IAQ Problems
The purpose of this section is to provide an understanding of basic principles in solving IAQ problems. This guidance can be helpful in selecting a mitigation strategy and in evaluating the practicality and effectiveness of proposals from outside professionals or in-house staff.
- Developing Solutions
- Solutions for Other Complaints
- Evaluating Solutions
- Evaluating the Effectiveness of Your Solution
- Persistent Problems
If people are provided with information, they can act to reduce pollutant exposure.
The selection of a solution is based on the data gathered during diagnostics (Section 5: "Diagnosing IAQ Problems"). The diagnostics may have determined that the problem was either a real or a perceived IAQ problem, or a combination of multiple problems. For each problem that is identified, develop a solution using the basic control strategies described below. See Section 5.
There are six basic control methods that can lower concentrations of indoor air pollutants. Often, only a slight shift in emphasis or action using these control methods is needed to control IAQ more effectively. Specific applications of these basic control strategies can be found in each team member’s checklist.
1. Source Management
Managing pollutant sources, the most effective control strategy, includes:
- Source removal — Eliminating or not allowing pollutant sources to enter the school. Examples include:
- Not allowing buses to idle, especially not near outdoor air intakes
- Not placing garbage in rooms with HVAC equipment
- and replacing moldy materials
- Source reduction — Improving technology and/or materials to reduce emissions. Examples include:
- Replacing 2-stroke lawn and garden equipment with lower emitting options (e.g., manual or electrically powered or 4-stroke)
- Switching to low emissions portable gasoline containers
- and implementing technology upgrades to reduce emissions from school buses
- Source substitution — Replacing pollutant sources. Examples include selecting less- or non-toxic art materials or interior paints.
- Source encapsulation — Placing a barrier around the source so that it releases fewer pollutants into the indoor air. Examples include covering pressed wood cabinetry with sealed or laminated surfaces or using plastic sheeting when renovating to contain contaminants.
2. Local Exhaust
Removing (exhausting fume hoods and local exhaust fans to the outside) point sources of indoor pollutants before they disperse. Examples include exhaust systems for:
- Restrooms and kitchens
- Science labs
- Storage rooms
- Printing and duplicating rooms
- and vocational/industrial areas (such as welding booths and firing kilns)
Lowering pollutant concentrations by diluting polluted (indoor) air with cleaner (outdoor) air. Local building codes likely specify the quantity (and sometimes quality) of outdoor air that must be continuously supplied in your school. (If not, see Section 2 of this Guide for ASHRAE recommendations.) Temporarily increasing ventilation as well as properly using the exhaust system while painting or applying pesticides, for example, can be useful in diluting the concentration of noxious fumes in the air. See Section 2.
4. Exposure Control
Adjusting the time and location of pollutant exposure. Location control involves moving the pollutant source away from occupants or even relocating susceptible occupants.
- Time of use — Avoid use of pollutant sources when the school is occupied. For example, strip and wax floors (with the ventilation system functioning) on Friday after school is dismissed. This allows the floor products to off-gas over the weekend, reducing the level of pollutants in the air when the school is reoccupied on Monday. Another example is to mow around the building and near play fields only before or after school hours.
- Amount of use — Use air-polluting sources as little as possible to minimize contamination of the indoor air.
- Location of use — Move polluting sources as far away as possible from occupants or relocating susceptible occupants.
5. Air Cleaning
Filtering particles and gaseous contaminants as air passes through ventilation equipment. This type of system should be engineered on a case-by-case basis.
Teaching and training school occupants about IAQ issues. People in the school can reduce their exposure to many pollutants by understanding basic information about their environment and knowing how to prevent, remove, or control pollutants.
Some solutions, such as major ventilation changes, may not be practical to implement due to lack of resources or the need for long periods of non-occupancy to ensure the safety of the students and staff. Use temporary measures to ensure good IAQ in the meantime. Other solutions, such as anti-idling programs, offer low-cost options that can be easily and quickly implemented.
Solutions for Other Complaints
Specific lighting deficiencies or localized sources of noise or vibration may be easily identified. Remedial action may be fairly straightforward, such as having more or fewer lights, making adjustments for glare and relocating, replacing, or acoustically insulating a noise or vibration source.
In other cases, where problems may be more subtle or solutions more complex, such as psychogenic illnesses (originating in the mind), enlist the services of a qualified professional.
Remedial actions for lighting and noise problems can range from modifications of equipment or furnishings to renovation of the building. Reducing stress for school staff may involve new management practices, job redesign, or resolution of underlying labor-management problems.
To help ensure a successful solution, evaluate mitigation efforts at the planning stage by considering the following criteria:
- Operating principle
- Installation and operating cost
- Control capacity
- Ability to institutionalize the solution
- Conformity with codes
Mitigation efforts that create permanent solutions to indoor air problems are clearly superior to those that provide temporary solutions, unless the problems are also temporary. Opening windows or running air handlers on full outdoor air may be suitable mitigation strategies for a temporary problem, such as off-gassing of volatile compounds from new furnishings, but they are not acceptable permanent solutions because of increased costs for energy and maintenance. A permanent solution to microbiological contamination involves cleaning and disinfection as well as moisture control to prevent regrowth.
IAQ solutions that are durable are more attractive than approaches that require frequent maintenance or specialized skills. New items of equipment should be quiet, energy-efficient and durable.
The operating principle of the IAQ solution needs to make sense and be suited to the problem. If a specific point source of contaminants is identified, treatment at the source by removal, sealing, or local exhaust is a more appropriate correction strategy than diluting the contaminant with increased ventilation. If the IAQ problem is caused by outdoor air containing contaminants, then increasing the outdoor air supply will only worsen the situation, unless the supply of outdoor air is cleaned.
Installation and Operating Costs
The approach with the lowest initial cost may not be the least expensive over the long run. Long-term economic considerations include:
- Energy costs for equipment operation
- Increased staff time for maintenance
- Differential cost of alternative materials and supplies
- and higher hourly rates
Strong consideration should be given to purchasing ENERGY STAR qualified products.
It is important to select a solution that fits the size and scope of the problem. If odors from a special use area such as a kitchen entering nearby classrooms, increasing the ventilation rate in the classrooms may not be successful. If mechanical equipment is needed to correct the IAQ problem, it must be powerful enough to accomplish the task. For example, a local exhaust system should be strong enough and close enough to the source so that none of the contaminant moves into other portions of the building.
Ability to Institutionalize the Solution
A solution will be most successful if it is integrated into normal building operations. To ensure success, solutions should not require exotic equipment, unfamiliar concepts, or delicately maintained systems. If maintenance, housekeeping procedures, or supplies must change as part of the solution, it may be necessary to provide additional training, new inspection checklists, or modified purchasing guidelines. Operating and maintenance schedules for heating, cooling and ventilation equipment may also need modification.
Conformity with Codes
Any modification to building components or mechanical systems should be designed and installed in conformance with applicable fire, electrical and other building codes.
Evaluating the Effectiveness of Your Solution
Two kinds of indicators can be used to evaluate the success of correcting an indoor air problem:
- Reduced complaints.
- Measurement of the properties of the indoor air.
A solution will be most successful if it is integrated into normal building operations.
Although reduction or elimination of complaints appears to be a clear indication of success, it may not necessarily be the case. Occupants who feel their concerns are being heard may temporarily stop reporting discomfort or health symptoms, even if the actual cause of their complaints has not been corrected. On the other hand, lingering complaints may continue after successful mitigation if people are upset over the handling of the problem. A smaller number of ongoing complaints may indicate that multiple IAQ problems exist and have not been resolved.
Measurements of airflows, ventilation rates and air distribution patterns can be used to assess the results of control efforts. Airflow measurements taken during the building investigation can identify areas with poor ventilation; later they can be used to evaluate attempts to improve the ventilation rate, distribution, or direction of flow. Studying air distribution patterns will show whether a mitigation strategy has successfully prevented the transportation of a pollutant by airflow. While in some cases measuring pollutant levels can help determine whether IAQ has improved, in many cases this may be difficult and/or cost prohibitive. Concentrations of indoor air pollutants typically vary greatly over time, and the specific contaminant measured may not be causing the problem. Measuring a specific pollutant by a professional is appropriate if the problem can be limited to that pollutant. For further information on IAQ measurements, see Appendix B: "Basic Measurement Equipment."
Ongoing complaints may indicate that multiple IAQ problems have not been resolved.
Sometimes even the best-planned investigations and mitigation actions will not resolve the problem. You may have carefully investigated the problem, identified one or more causes and implemented a control system. Nonetheless, your efforts may not have noticeably reduced the concentration of the contaminant or improved ventilation rates or efficiency. Worse, the problem may continue to persist.
If your efforts to control a problem are unsuccessful, consider seeking outside assistance. The problem could be fairly complex, occur only intermittently, or extend beyond traditional fields of knowledge. It is possible that poor IAQ is not the actual cause of the complaints. Bringing in a new perspective at this point can be very effective. Appendix A: "Hiring Professional Assistance" provides guidance on hiring professional IAQ assistance.
Appendix A - Hiring Professional Assistance
Some indoor air quality (IAQ) problems are simple to resolve when school personnel understand the building investigation process. Many potential problems will be prevented if staff and students do their part to maintain good IAQ. However, a time may come when outside assistance is needed. For example, professional help might be necessary or desirable in the following situations:
- If you suspect that you have a serious building-related illness potentially linked to biological contamination in your building, mistakes or delays could have serious consequences (such as health hazards, liability exposure, regulatory sanctions). Contact your local or state Health Department.
- Testing for a public health hazard (such as asbestos, lead, or radon) has identified a problem that requires a prompt response.
- The school administration believes that an independent investigation would be better received or more effectively documented than an in-house investigation.
- Investigation and mitigation efforts by school staff have not relieved an IAQ problem.
- Preliminary findings by staff suggest the need for measurements that require specialized equipment and skills that are not available in-house.
- Hiring Professional Help
- Evaluating Potential Consultants
- IAQ-Related Ventilation Modifications
Hiring Professional Help
As you prepare to hire professional services for a building investigation, be aware that IAQ is a developing area of knowledge. Most individuals working in IAQ received their primary training in other disciplines. It is important to define the scope of work clearly and discuss any potential consultant’s proposed approach to the investigation, including plans for coordinating efforts among team members. The school’s representatives must exercise vigilance in overseeing diagnostic activities and corrective action. Performance specifications can help to ensure the desired results. Sample performance specification language is provided at the end of this appendix in italicized font.
Other than for lead and asbestos remediation, there are no Federal regulations covering professional services in the general field of indoor air quality, although some disciplines (e.g., engineers, industrial hygienists) whose practitioners work with IAQ problems have licensing and certification requirements. Individuals and groups that offer services in this evolving field should be questioned closely about their related experience and their proposed approach to your problem. In addition, request and contact references.
Local, state, or Federal government agencies (e.g., education, health, or air pollution agencies) may be able to provide expert assistance or direction in solving IAQ problems. If available government agencies do not have personnel with the appropriate skills to assist in solving your IAQ problem, they may be able to direct you to firms in your area with experience in IAQ work. You may also be able to locate potential consultants by looking in the yellow pages e.g., under:
- Environmental Services
- Laboratories – Testing
- or Industrial Hygienists
or by asking other schools for referrals. Often, a multi-disciplinary team of professionals is needed to investigate and resolve an IAQ problem. The skills of heating, ventilation and air-conditioning (HVAC) engineers and industrial hygienists are typically useful for this type of investigation. Input from other disciplines such as:
- or medicine
may also be important.
If problems other than IAQ are involved, experts in:
- acoustic design
- interior design
- or other fields
may be helpful in resolving occupant complaints about the indoor environment.
Evaluating Potential Consultants
As with any hiring process, the better you know your own needs, the easier it will be to select individuals or firms to service those needs. The more clearly you can define the project scope, the more likely you are to achieve the desired result without paying for unnecessary services. An investigation strategy based on evaluating building performance can be used to solve a problem without necessarily identifying a particular chemical compound as the cause. The idea of testing the air to learn whether it is "safe" or "unsafe" is very appealing. Most existing standards for airborne pollutants, however, were developed for industrial settings where most occupants are usually healthy adult men. Some state regulations call for the involvement of a professional engineer for any modifications or additions to a school HVAC system. Whether or not this is legally mandated for your school, the professional engineer’s knowledge of air handling, conditioning and sequencing strategies will help to design ventilation system modifications without creating other problems. In many situations, proper engineering can save energy while improving IAQ. An example of this might be the redesign of outside air-handling strategies to improve the performance of an economizer cycle.
The following guidelines may be helpful in evaluating potential consultants:
- Competent professionals will ask questions about your situation to see whether they can offer services that will assist you.
The causes and potential remedies for IAQ problems vary greatly. A firm needs at least a preliminary understanding of the facts about what is going on in your building to evaluate if it can offer the professional skills necessary to address your concerns and to make effective use of its personnel from the outset.
- Consultants should be able to describe how they expect to form and test explanations for and solutions to the problem.
Discuss the proposed approach to the building investigation. It may involve moving suspected contaminant sources or manipulating HVAC controls to simulate conditions at the time of complaints or to test possible corrective actions. Poorly designed studies may lead to conclusions that are either "false negative" (i.e., falsely concluding that there is no problem) or "false positive" (i.e., falsely concluding that a specific condition caused the complaint).
Some consultants may produce an inventory of problems in the building without determining which, if any, of those problems caused the original complaint. If investigators discover IAQ problems unrelated to the concern that prompted the evaluation, those problems should be noted and reported. It is important, however, that the original complaint is resolved.
- The decision to take IAQ measurements should be approached with caution. IAQ investigators often find a large number of potential sources contributing low levels of various contaminants to the air. These findings frequently raise more questions than they answer. Before starting to take measurements, investigators need a clear understanding of how the results will be used and interpreted. Without this understanding, planning appropriate sampling locations and times, instrumentation and analysis procedures is impossible. Non-routine measurements (such as relatively expensive sampling for volatile organic compounds (VOCs)) should not be conducted without site-specific justification. Concentrations that comply with industrial occupational standards are not necessarily protective of children, or other school occupants.
- A qualified IAQ investigator should have appropriate experience, demonstrate a broad understanding of IAQ problems and the conditions that can lead to them e.g., the relationship between IAQ and
- the building structure
- mechanical systems
- and human activities
Have the firm identify the personnel who would be responsible for your case, their specific experience, and related qualifications. Contract only for the services of those individuals, or require approval for substitutions. When hiring an engineer, look for someone with the equipment and expertise to perform a ventilation system assessment and with strong field experience. Some engineers rarely work outside the office.
- In the proposal and the interview, a prospective consultant should present a clear, detailed picture of the proposed services and work products, including the following information:
- The basic goal(s), methodology and sequence of the investigation, the information to be obtained and the process of hypothesis development and testing, including criteria for decision-making about further data-gathering.
- Any elements of the work that will require a time commitment from school staff, including information to be collected by the school.
- The schedule, cost and work product(s), such as a written report, specifications and plans for mitigation work; supervision of mitigation work and training program for school staff.
- Additional tasks (and costs) that may be part of solving the IAQ problem but are outside the scope of the contract. Examples include: medical examination of complainants, laboratory fees and contractor’s fees for mitigation work.
- Communication between the IAQ professional and the client: How often will the contractor discuss the progress of the work with the school? Who will be notified of test results and other data? Will communications be in writing, by telephone, or face-to-face? Will the consultant meet with students and/or school staff to collect information? Will the consultant meet with staff, parent organizations, or others to discuss findings, if requested to do so?
- References from clients who have received comparable services.
IAQ-Related Ventilation Modifications
The school’s representatives need to remember: Oversee the work and ask questions that will help you ensure the work is properly performed. Specialized measurements of airflow or pre- and post-mitigation contaminant concentrations may be needed to know whether the corrective action is effective.
Performance specifications can be used as part of the contract package to establish critical goals for system design and operation. Performance specifications can be used to force contractors to demonstrate that they have met those goals. At the same time, performance specifications should avoid dictating specific design features such as duct sizes and locations, thus leaving HVAC system designers free to apply their professional expertise. You may be able to adapt appropriate sections of the following sample performance specifications for your school.
- The control system shall be modified and the ventilation system repaired and adjusted as needed to provide outdoor air ventilation during occupied hours. The amount of outdoor air ventilation shall meet ASHRAE Standard 62-2001 minimum recommendations or shall be the maximum possible with the current air-handling equipment, but in no case shall the minimum outdoor air ventilation rate be less than the ventilation guideline in effect at the time the school was constructed.
- When designing the ventilation system modifications, it is important to ensure that:
- Increased outdoor air intake rates do not negatively impact occupant comfort
- heating coils do not freeze
- the cooling system can handle the increased enthalpy load
- If the existing plant cannot meet this load or, if for some other reason, it is decided not to use the existing heating system to condition outdoor air, then a heating (or cooling) plant shall be designed for that purpose. The proposal shall include a life-cycle cost analysis of energy conservation options (e.g., economizer cooling, heat recovery ventilation).
- All screens in outdoor air intakes shall be inspected for proper mesh size. Screens with mesh size smaller than 1/2 inch are subject to clogging; if present, they shall be removed and replaced with larger-sized mesh (not so large as to allow birds to enter).
Demonstrating System Performance
- The proper operation of control sequence and outdoor air damper operation shall be verified by school personnel or the school’s agent after ventilation system modifications and repairs have been completed. This shall include, but not be limited to:
- observation of damper position for differing settings of low limit stats and room stats
- measurement of air pressure at room stats and outdoor air damper actuators
- direct measurement of air flow through outdoor air intakes
- and direct measurement of air flows at exhaust grilles
- Test procedures used to evaluate ventilation system performance
- test locations
- HVAC operating conditions during testing
- and findings
Institutionalizing the Corrective Action
- After the ventilation system modifications are completed, school facility operators shall be provided with training and two copies of a manual that documents the ventilation system control strategy, operating parameters and maintenance requirements.
Appendix B - Basic Measurement Equipement
To prevent or resolve indoor air quality (IAQ) problems effectively and efficiently, you must be able to take our basic measurements relating to the air within the school. Your school or school district may already own some or all of the equipment necessary to make these measurements. If not, buying or borrowing that equipment is important to assess the IAQ conditions in your school accurately and ensure that the ventilation equipment is working properly (which can save the school money in heating and cooling bills), as well as improve IAQ. Check with your EPA regional office about equipment availability. For a complete list of EPA regional offices see Appendix L: "Resources".
Four measurements are important to the activities in this Guide:
- Relative humidity.
- Air movement.
- Airflow volume.
In addition, a carbon dioxide (CO2) monitor is useful for indicating when outdoor air ventilation may be inadequate. See the Ventilation Checklist.
Sampling for pollutants is not recommended, since results are difficult to interpret and can require costly measurement equipment as well as significant training and experience. The activities described in this Guide are likely to prevent or uncover problems more effectively than pollutant sampling. The four measurements listed above are readily available, do not require expensive equipment or special training and are straightforward to interpret.
If your school’s budget does not allow the purchase of some or all of the equipment, try a cooperative approach:
- Combine resources with other schools in the district or neighboring schools.
- Contact school organizations and local government to inquire about cooperative purchasing options.
- Borrow equipment from:
- another school
- a state or local government
- or an EPA regional office
Do not let a lack of equipment prevent you from conducting the recommended activities. Conduct as many activities as possible with the equipment you have available. If you cannot obtain the recommended equipment due to lack of resources, prioritize your equipment purchases as follows:
- Temperature, relative humidity and chemical smoke device for indicating air movement;
- Airflow volume measuring devices; and
- CO2 monitor.
Appendix C - Codes and Regulations
The Federal government has a long history of regulating outdoor air quality and the concentrations of airborne contaminants in industrial settings. In an industrial environment, specific chemicals released by industrial processes can be present in high concentrations. It has been possible to study the health effects of industrial exposures and establish regulations to limit those exposures.
Some states have established regulations regarding specific pollutants in schools, such as testing for radon and lead. Various States have also established anti-idling policies that establish maximum idling times for school buses and other vehicles.
Indoor air quality (IAQ) in schools, however, presents a different problem. A large variety of chemicals used in:
- grounds maintenance
- and kitchen and cleaning applications
exist at levels that are almost always lower than the concentrations found in industry. The individual and combined effects of these chemicals are very difficult to study, and the people exposed may include pregnant women, children and others who are more susceptible to health problems than the adult typically present in regulated industrial settings.
There is still much to learn about the effects of both acute (short-term) and chronic (long-term) exposure to low levels of multiple indoor air contaminants. At this time, there are few Federal regulations for airborne contaminants in non-industrial settings. The Occupational Safety and Health Administration (OSHA) is the Federal agency responsible for workplace safety and health. In the past, OSHA focused primarily on industrial worksites, but most recently has broadened its efforts to address other worksite hazards. In spring 1994, OSHA introduced a proposed rule regarding IAQ in non-industrial environments, although the proposal was withdrawn in December 2001. School employees may be able to obtain advice (in the form of training and information) from their state OSHA office on how to reduce their exposure to potential air contaminants. In states without OSHA organizations, the regional OSHA contact may be able to provide information or assistance. See Appendix L: " Resources".
Ventilation is the other major influence on IAQ that is subject to regulation. The Federal government does not regulate ventilation in non-industrial settings. However, many state and local governments do regulate ventilation system capacity through their building codes. Building codes have been developed to promote good construction practices and prevent health and safety hazards. Professional associations, such as the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) and the National Fire Protection Association (NFPA), develop recommendations for appropriate building and equipment design and installation (e.g., ASHRAE Standard 62-2001, "Ventilation for Acceptable Indoor Air Quality"). Those recommendations acquire the force of law when adopted by state or local regulatory bodies. There is generally a time lag between the adoption of new standards by consensus organizations such as ASHRAE and the incorporation of those new standards as code requirements. Contact your local code enforcement official, your State’s Education Department, or a consulting engineer to learn about the code requirements that apply to your school.
In general, building code requirements are only enforceable during construction and renovation. When code requirements change over time (as code organizations adapt to new information and technologies), buildings are usually not required to modify their structure or operation to conform to the new codes. Indeed, many buildings do not operate in conformance with current codes, or with the codes they had to meet at the time of construction. For example, the outdoor air flows that ASHRAE’s Standard 62 recommends for classrooms were reduced from 30 cubic foot per minute (cfm)/person to 10 cfm/person in the 1930s, and reduced again to 5 cfm/person in 1973 in response to higher heating fuel costs resulting from the oil embargo. Concern about IAQ stimulated reconsideration of the standard, so that its most recent version, Standard 62-2001, calls for a minimum of 15 cfm/person in classrooms. However, many schools that reduced outdoor air flow during the energy crisis continue to operate at ventilation rates of 5 cfm/person or less. This under ventilation is contrary to current engineering recommendations, but, in most jurisdictions, it is not against the law.
Appendix D - Asthma
Asthma has reached epidemic proportions in the United States, affecting millions of people of all ages and races. Asthma is one of the leading causes of school absenteeism, accounting for more than 14 million missed school days in 2001.
Asthma can occur at any age but is more common in children than in adults. According to the Centers for Disease Control and Prevention (CDC), asthma is the third-ranking cause of hospitalization for children 15 years of age and under. Moreover, the asthma rate among children ages 5 to 14 rose 74 percent between 1980 and 1994, making asthma the most common chronic childhood disease.
What is Asthma?
Asthma is a chronic disease typically characterized by inflammation of the airways. During an asthma episode, the airways in the lungs narrow, making breathing difficult. Symptoms usually include:
- shortness of breath
- tightness in the chest
- and coughing.
Asthma attacks are often separated by symptom-free periods. The frequency and severity of asthma attacks can be reduced by following a comprehensive asthma management plan that incorporates medical treatment and environmental management of asthma. While scientists do not fully understand the causes of asthma, outdoor air pollution and environmental contaminants commonly found indoors are known to trigger asthma attacks. See EPA's Asthma page.
Because Americans spend up to 90 percent of their time indoors, exposure to indoor allergens and irritants may play a significant role in triggering asthma episodes. Some of the most common environmental asthma triggers found indoors include:
Other asthma triggers include:
- respiratory infections
- pollens (trees, grasses, weeds)
- outdoor air pollution
- food allergies
- and cold air exposure
Any warm-blooded animal -- including:
- and rats
-- can cause allergic reactions or trigger asthma attacks. Proteins may act as allergens in the dander, urine, or saliva of warm-blooded animals. The most common source of animal allergens in schools is a pet in the classroom. If an animal is present in the school, direct exposure to the animal’s dander and bodily fluids is possible. It is important to realize that, even after extensive cleaning, pet allergen levels may stay in the indoor environment for several months after the animal is removed.
Schools can minimize exposure to animal allergens by:
- Seating sensitive students away from pets or considering removing pets from the classroom.
- Vacuuming the classroom frequently and thoroughly.
- Cleaning cages and the surrounding area regularly and positioning these cages away from ventilation systems.
Cockroaches and other pests, such as rats and mice, often exist in the school setting. Allergens from pests may be significant asthma triggers for students and staff in schools. Certain proteins that act as allergens in the waste products and saliva of cockroaches can cause allergic reactions or trigger asthma attacks in some individuals. Pest problems in schools may be caused or worsened by a variety of conditions such as plumbing leaks, moisture problems and improper food handling and storage practices. It is important to avoid exposure to these allergens through the use of commonsense approaches and integrated pest management (IPM) practices throughout the entire school.
Schools can minimize cockroach exposure by:
- Removing or covering food or garbage found in classrooms or kitchens.
- Storing food in airtight containers.
- Cleaning all food crumbs or spilled liquids immediately.
- Fixing plumbing leaks and other moisture problems.
- Using poison baits, boric acid (for cockroaches) and traps before applying pesticidal sprays.
- If pesticide sprays are used, the school should:
- Notify staff, students and parents before spraying.
- Limit spraying to the infested area.
- Only spray when rooms are unoccupied.
Ventilate the area well during and after spraying.
Mold and Moisture
Molds can be found almost anywhere; they can grow on virtually any substance when moisture is present. Molds produce tiny spores for reproduction that travel through the air continually. When mold spores land on a damp spot indoors, they may begin growing and digesting whatever they are growing on in order to survive. Molds can grow on:
- and food
If excessive moisture or water accumulates indoors, extensive mold growth may occur, particularly if the moisture problem remains undiscovered or ignored. Eliminating all mold and mold spores in the indoor environment is impractical -- the way to control indoor mold growth is to control moisture.
When mold growth occurs in buildings, reports of health-related symptoms from some building occupants, particularly those with allergies or respiratory problems, may follow. Potential health effects and symptoms associated with mold exposures include allergic reactions, asthma and other respiratory complaints.
Schools can minimize mold and moisture exposure by:
- Fixing plumbing leaks and other unwanted sources of water.
- Ensuring that kitchen areas and locker rooms are well ventilated.
- Maintaining low indoor humidity, ideally between 30 and 60 percent. The humidity level can be measured with a hygrometer, available at local hardware stores.
- Cleaning mold off hard surfaces with water and detergent, then drying completely.
- Replacing absorbent materials, such as ceiling tiles and carpet, if they are contaminated with mold.
Secondhand smoke is the smoke from the burning end of a cigarette, pipe, or cigar or the smoke exhaled by a smoker. Secondhand smoke exposure causes a number of serious health effects in young children, such as:
- ear infections
- reduced lung function
- and more severe asthma attacks.
Secondhand smoke is an irritant that may trigger an asthma episode, and increasing evidence suggests that secondhand smoke may cause asthma in pre-school aged children. EPA estimates that between 200,000 and 1,000,000 children with asthma have exacerbated asthma conditions caused by exposure to secondhand smoke. Secondhand smoke can also lead to buildup of fluid in the middle ear -- the most common reason for operations in children.
Most schools in the United States prohibit smoking on school grounds. However, smoking often occurs in school bathrooms, in lounges and near school entrances. If smoking occurs within the building, secondhand smoke can travel through the ventilation system to the entire school. Even when people smoke outside, secondhand smoke may enter the school through the ventilation system, windows and doors.
Schools can minimize exposure to secondhand smoke by implementing and enforcing nonsmoking policies, particularly indoors and near school entrances.
Dust mites are too small to be seen, but they are found in homes, schools and other buildings throughout the United States. Dust mites live in:
- fabric-covered furniture
- and stuffed toys.
Their primary food source is dead skin flakes. Dust mite allergens may cause an allergic reaction or trigger an asthma episode. In addition, there is evidence that dust mites may cause asthma.
Schools can minimize dust mite exposure by:
- Vacuuming carpet and fabric-covered furniture regularly. Use vacuums with high-efficiency filters or central vacuums, if possible.
- Removing dust from hard surfaces with a damp cloth and sweep floors frequently.
- Purchasing washable stuffed toys, washing them often in hot water and drying them thoroughly.
Combining steps for reducing environmental triggers with other proactive measures --
- relocating areas where vehicles (e.g., buses and delivery trucks) idle away from air intakes
- ensuring sufficient ventilation in classrooms and offices
- eliminating the use of air fresheners
- choosing building materials with minimal formaldehyde content
- and purchasing environmentally preferable cleaning products.
-- can help schools reduce student and staff exposure to asthma triggers.
Outdoor Air Pollution
Exposure to outdoor air pollution, such as diesel exhaust, ozone and particulate matter, can trigger an asthma episode or exacerbate asthma symptoms. There are simple actions that schools can take to minimize student and staff exposure to outdoor air pollutants.
Exposure to diesel exhaust from school buses and other diesel vehicles can exacerbate asthma symptoms. Diesel engines emit soot, also known as particulate matter (PM), as well as ozone-forming nitrogen oxides and other toxic air pollutants. PM and ozone (a primary ingredient of smog) are thought to trigger asthma symptoms and lung inflammation, resulting in:
- reduced lung function
- greater use of asthma medication
- increased school absences
- and more frequent visits to the emergency room and hospital
Diesel PM is also associated with more severe allergies and respiratory disease. In recent studies, outdoor ozone, or smog, has been associated with more frequent diagnoses of new asthma cases in children.
Schools can take simple steps to reduce exposure to diesel exhaust pollutants:
- Do not allow school buses or other vehicles such as delivery trucks to idle on school grounds and discourage carousing.
- Encourage your school bus fleet manager to implement district-wide anti-idling policies and practices.
- Work with your school bus fleet manager to replace the oldest buses and to reduce emissions from newer buses by retrofitting them with emission control technology and/or by switching to cleaner fuels.
- For more information, visit National Clean Diesel Campaign or call (734) 214-4780.
Ozone and Particulate Matter
The Air Quality Index (AQI) is a tool to provide the public with clear and timely information on local air quality and whether air pollution levels pose a health concern. The AQI is reported and forecasted every day in many areas throughout the United States on local weather reports and through national media. Asthma episodes are most likely to occur the day after outdoor pollution levels are high.
Schools can take simple steps to ensure the health and comfort of students when the AQI reports unhealthy levels:
- Limit physical exertion outdoors.
- Consider changing the time of day of strenuous outdoor activity to avoid the period when air pollution levels are high or consider postponing sports activities to another time.
Appendix E - Typical Indoor Air Pollutants
Presented is information about several indoor air pollutants common to schools, in a format that allows for easy comparison. A separate Adobe Acrobat version is also available: Appendix E.
The pollutants presented include:
- Biological contaminants
- Dust mites
- Pet dander
- Pollen, etc.
- Carbon dioxide (CO2)
- Carbon monoxide (CO)
- Environmental tobacco smoke (ETS) or secondhand smoke
- Fine particulate matter (PM2.5)
- Lead (Pb)
- and Nitrogen oxides (NO, NO2).
Each pollutant is described or analyzed across five categories:
- Standards and guidelines for indoor air quality
- Health effects
- Control measures
- Biological contaminants
- Carbon dioxide (CO2)
- Carbon monoxide (CO)
- Environmental tobacco smoke (ETS) or secondhand smoke
- Fine particulate matter (PM2.5)
- Lead (Pb)
- Nitrogen oxides (NO, NO2)
Description: Common biological contaminants include:
- Dust mites
- Pet dander (skin flakes)
- Droppings and body parts from cockroaches, rodents and other pests or insects
- and bacteria
Many of these biological contaminants are small enough to be inhaled.
Sources: Biological contaminants are, or are produced by, living things. Biological contaminants are often found in areas that provide food and moisture. Damp or wet areas can be moldy, such as
- Cooling coils
- Condensate pans
- or unvented bathrooms
Areas where dust collects may accumulate biological contaminants, such as:
- and other areas
Standards and Guidelines for Indoor Air Quality: There are currently no federal government standards for biologicals in school indoor air environments.
- Dust mites
- Pet dander
- and pest droppings or body parts
can trigger asthma. Biological contaminants, including molds and pollens can cause allergic reactions for a significant portion of the population.
- Staphylococcus infections
- and influenza
are known to be transmitted by air.
Control Measures: General good housekeeping, and maintenance of heating and air conditioning equipment, are very important. Adequate ventilation and good air distribution also help. The key to mold control is moisture control. If mold is a problem, get rid of excess water or moisture and clean up the mold. Maintaining the relative humidity between 30 and 60 percent will help control mold, dust mites, and cockroaches. Employ integrated pest management (IPM) to control insect and animal allergens. Cooling tower treatment procedures exist to reduce levels of Legionella and other organisms.
See also: Biological Pollutants.
Carbon Dioxide (CO2)
Description: Carbon dioxide (CO2) is a colorless, odorless product of carbon combustion.
Sources: Human metabolic processes and all combustion processes of carbon fuels, like those in cars, buses, trucks, etc., are sources of CO2. Exhaled air is usually the largest source of CO2 in classrooms.
Standards and Guidelines for Indoor Air Quality: ASHRAE Standard 62-2001 recommends 700 ppm above the outdoor concentration as the upper limit for occupied classrooms (usually around 1,000 ppm).
Health Effects: CO2 is an asphyxiate. At concentrations above 1.5 percent (15,000 ppm) some loss of mental acuity has been noted. (The recommended ASHRAE standard of 700 ppm above the outdoor concentration is to prevent body odor levels from being offensive.)
Control Measures: Ventilation with sufficient outdoor air controls CO2 levels. Reduce vehicle and lawn and garden equipment idling and/or usage.
Description: Carbon monoxide (CO) is a colorless, odorless gas. It results from incomplete oxidation of carbon in combustion processes.
Sources: Common sources of CO in schools are improperly vented furnaces, malfunctioning gas ranges, or exhaust fumes that have been drawn back into the building. Worn or poorly adjusted and maintained combustion devices (e.g., boilers, furnaces), or a flue that is:
- Improperly sized
- or leaking
can be significant sources. Auto, truck, or bus exhaust from attached garages, nearby roads, or idling vehicles in parking areas can also be sources.
Standards and Guidelines for Indoor Air Quality: The OSHA standard for workers is no more than 50 ppm for 1 hour of exposure. NIOSH recommends no more than 35 ppm for 1 hour. The U.S. National Ambient Air Quality Standards for CO are 9 ppm for 8 hours and 35 ppm for 1 hour. The Consumer Product Safety Commission recommends levels not to exceed 15 ppm for 1 hour or 25 ppm for 8 hours.
Health Effects: CO is an asphyxiate. An accumulation of this gas may result in a variety of symptoms deriving from the compound's affinity for and combination with hemoglobin, forming carboxyhemoglobin (COHb) and disrupting oxygen transport. Tissues with the highest oxygen needs — myocardium, brain and exercising muscle — are the first affected. Symptoms may mimic influenza and include:
- Nausea and vomiting
- Cognitive impairment
- and tachycardia
At high concentrations CO exposure can be FATAL.
Control Measures: Combustion equipment must be maintained to assure that there are no blockages and air and fuel mixtures must be properly adjusted to ensure more complete combustion. Vehicular use should be carefully managed adjacent to buildings and in vocational programs. Additional ventilation can be used as a temporary measure when high levels of CO are expected for short periods of time.
Description: Dust is made up of particles in the air that settle on surfaces. Large particles settle quickly and can be eliminated or greatly reduced by the body's natural defense mechanisms. Small particles are more likely to be airborne and are capable of passing through the body's defenses and entering the lungs.
Sources: Many sources can produce dust including:
- Fleecy surfaces
- Lead-based paint
- and burning of wood, oil or coal
Standards and Guidelines for Indoor Air Quality: The EPA Ambient Air Quality standard for particles less than 10 microns is 50 µg/m3 per hour for an annual average and 150 µg/m3 for a 24-hour average.
Health Effects: Health effects vary depending upon the characteristics of the dust and any associated toxic materials. Dust particles may contain:
- Pesticide residues
- or other toxic materials
Other particles may be irritants or carcinogens (e.g. asbestos).
Control Measures: Keep dust to a minimum with good housekeeping. Consider damp dusting and high efficiency vacuum cleaners. Upgrade filters in ventilation systems to medium efficiency when possible and change frequently. Exhaust combustion appliances to the outside and clean and maintain flues and chimneys. When construction or remodeling is underway, special precautions should be used to separate work areas from occupied areas.
Environmental Tobacco Smoke (ETS), or secondhand smoke
Description: Tobacco smoke consists of:
- Solid particles
- Liquid droplets
- and gases resulting from tobacco combustion.
Over 4000 specific chemicals have been identified in the particulate and associated gases.
Sources: Tobacco product combustion
Standards and Guidelines for Indoor Air Quality: Many office buildings and areas of public assembly have banned smoking indoors, or required specially designated smoking areas with dedicated ventilation systems be available. The "Pro-Children Act of 1994" prohibits smoking in Head Start facilities, and in kindergarten, elementary and secondary schools that receive Federal funding from the Department of Education, the Department of Agriculture, or the Department of Health and Human Services (except Medicare or Medicaid).
Health Effects: The effects of tobacco smoke on smokers include:
- Nasal congestion
- Persistent cough
- Conjunctival irritation
- Exacerbation of chronic respiratory conditions
Secondhand smoke has been classified as a "Group A" carcinogen by EPA and has multiple health effects on children. It has also been associated with:
- The onset of asthma
- Increased severity of or difficulty in controlling asthma
- Frequent upper respiratory infections
- Persistent middle-ear effusion
- Repeated pneumonia
Control Measures: Smoke outside away from air intakes. Smoke only in rooms that are properly ventilated and exhausted to the outdoors.
See also: Smoke-free Homes.
Fine Particulate Matter (PM2.5)
Description: Fine Particulate Matter (PM2.5), or soot, is a component of diesel exhaust, and is less than 2.5 microns in diameter, in comparison, the average human hair is about 100 microns thick. It may consist as a tiny solid or liquid droplet containing a variety of compounds.
Sources: The main source of PM2.5 is diesel engines in trucks, buses and non road vehicles, e.g.,
- and locomotive
Diesel engines emit large quantities of harmful pollutants annually.
Standards and Guidelines for Indoor Air Quality: There are currently no Federal government standards for PM2.5 in school indoor air environments. EPA's National Ambient Air Quality Standards list 15 µg/m3 as the annual limit and 65 µg/m3 as the 24-hour limit for PM2.5 in outdoor air.
Health Effects: Particulate matter is associated with a variety of serious health effects, including lung disease, asthma and other respiratory problems. In general, children are especially sensitive to air pollution because they breathe 50 percent more air per pound of body weight than adults. Fine particulate matter or PM2.5, poses the greatest health risk, because it can pass through the nose and throat and become lodged in the lungs. The particles can aggravate existing respiratory conditions, such as asthma and bronchitis, and they have been directly associated with increased hospital admissions and emergency room visits for heart and lung disease, decreased lung function and premature death. Short-term exposure may cause:
- Shortness of breath
- Eye and lung irritation
- and possible allergy aggravations.
Control Measures: Effective technologies to reduce PM2.5 include particulate filters and catalysts that can be installed on buses. An easy, no-cost, and effective way to control fine particulate matter is to minimize idling by buses, trucks and other vehicles.
Description: Lead is a highly toxic metal.
Sources: Sources of lead include:
- Drinking water
- Contaminated soil and dust
- and air.
Lead-based paint is a common source of lead dust.
Standards and Guidelines for Indoor Air Quality: In 1978, the Consumer Product Safety Commission banned lead in paint.
Health Effects: Lead can cause serious damage to the:
- Nervous system
- and red blood cells.
Children are particularly vulnerable. Lead exposure in children can result in:
- Delays in physical development
- Lower IQ levels
- Shorter attention spans
- and an increase in behavioral problems.
Control Measures: Preventive measures to reduce lead exposure in buildings painted before 1978 include:
- Cleaning play areas
- Frequently mopping floors and wiping window ledges and other smooth flat areas with damp cloths
- Keeping children away from areas where paint is chipped, peeling, or chalking
- Preventing children from chewing on window sills and other painted areas
- and ensuring that toys are cleaned frequently and hands are washed before meals.
Nitrogen Oxides (NO, NO2)
Description: The two most prevalent oxides of nitrogen are nitrogen dioxide (NO2) and nitric oxide (NO). Both are toxic gases, and NO2 is a highly reactive oxidant and corrosive.
Sources: The primary sources indoors are combustion processes, such as unvented combustion appliances, e.g.
- Gas stoves
- Vented appliances with defective installations
- and tobacco smoke.
Outdoor sources, such as vehicles and lawn and garden equipment, also contribute to nitrogen oxide levels.
Standards and Guidelines for Indoor Air Quality: No standards have been agreed upon for nitrogen oxides in indoor air. ASHRAE and the US. EPA National Ambient Air Quality Standards list 0.053 ppm as the average 24-hour limit for NO2 in outdoor air.
Health Effects: NO2 acts mainly as an irritant affecting:
- The mucosa of the eyes
- and respiratory tract.
Extremely high-dose exposure (as in a building fire) to NO2 may result in pulmonary edema and diffuse lung injury. Continued exposure to high NO2 levels can contribute to the development of acute or chronic bronchitis. Low-level NO2 exposure may cause increased bronchial reactivity in some asthmatics, decreased lung function in patients with chronic obstructive pulmonary disease and increased risk of respiratory infections, especially in young children.
Control Measures: Venting the NO2 sources to the outdoors and assuring that combustion appliances are correctly installed, used and maintained are the most effective measures to reduce exposures. Develop anti-idling procedures for all vehicles and non road engines:
- Lawn and garden equipment
Appendix F - Secondhand Smoke
Secondhand smoke, also known as environmental tobacco smoke (ETS), is a mixture of the smoke given off by the burning end of a cigarette, pipe, or cigar and the smoke exhaled from the lungs of smokers. This mixture contains more than 4,000 substances, more than 40 of which are known to cause cancer in humans or animals and many of which are strong irritants. Exposure to secondhand smoke is called involuntary smoking or passive smoking.
EPA has classified secondhand smoke as a known cause of cancer in humans (Group A carcinogen). Passive smoking causes an estimated 3,000 lung cancer deaths in nonsmokers each year. It also causes irritation of the:
- and lungs.
ETS-induced irritation of the lungs leads to:
- Excess phlegm
- Chest discomfort
- and reduced lung function.
Secondhand smoke may also affect the cardiovascular system, and some studies have linked exposure to it with the onset of chest pain.
Secondhand smoke Effects on Children
Secondhand smoke is a serious health risk to children. Children whose parents smoke are among the most seriously affected by exposure to secondhand smoke, being at increased risk of lower respiratory tract infections such as pneumonia and bronchitis. EPA estimates that passive smoking is responsible for between 150,000 and 300,000 lower respiratory tract infections in infants and children under 18 months of age annually, resulting in 7,500 to 15,000 hospitalizations per year.
Children exposed to secondhand smoke are also more likely to have reduced lung function and symptoms of respiratory irritation like coughing, excess phlegm and wheezing. Passive smoking can lead to a buildup of fluid in the middle ear, the most common cause of hospitalization of children for an operation.
Asthmatic children are especially at risk. EPA estimates that exposure to secondhand smoke increases the number of episodes and severity of symptoms in between 200,000 and 1,000,000 asthmatic children. Passive smoking is also a risk factor for the development of asthma in thousands of children each year.
EPA recommends that every organization dealing with children have a smoking policy that effectively protects children from exposure to secondhand smoke. Parent-teacher associations, school board members and school administrators should work together to make school environments smoke-free. Key features of smoking education programs include:
- Multiple sessions over many grades
- Social and physiological consequences of tobacco use
- Information about social influences (peers, parents and media)
- and training in refusal skills.
School-based non-smoking policies are important because the school environment should be free from secondhand smoke for health reasons and because teachers and staff are role models for children.
In general, the Federal government does not have regulatory authority over indoor air or secondhand smoke policies at the state or local level. Restricting smoking in public places is primarily a state and local issue, and is typically addressed in clean indoor air laws enacted by states, counties and municipalities. However, the "Pro-Children Act of 1994" prohibits smoking in Head Start facilities and in kindergarten, elementary and secondary schools that receive Federal funding from the Department of Education, the Department of Agriculture, or the Department of Health and Human Services (except funding from Medicare or Medicaid). The Act was signed into law as part of the "Goals 2000: Educate America Act."
What follows are excerpts from the Act, which took effect December 26, 1994.
Pro-Children Act of 1994
Following are excerpts from Public Law 103-227, March 31, 1994.
Section 1042. Definitions.
(1) CHILDREN. The term "children" means individuals who have not attained the age of 18.
(2) CHILDREN’S SERVICES. The term "children’s services" means the provision on a routine or regular basis of health, day care, education, or library services —
(A) That are funded, after the date of the enactment of this Act, directly by the Federal government or through state or local governments, by Federal grant, loan, loan guarantee, or contract programs —
(i) Administered by either the Secretary of Health and Human Services or the Secretary of Education (other than services provided and funded solely under titles XVIII and XIX of the Social Security Act); or
(ii) Administered by the Secretary of Agriculture in case of a clinic; or
(B) That are provided in indoor facilities that are constructed, operated, or maintained with such Federal funds, as determined by the appropriate Secretary in any enforcement action under this title, except that nothing in clause (ii) of subparagraph (A) is intended to include facilities (other than clinics) where coupons are redeemed under the Child Nutrition Act of 1966.
(3) PERSON. The term "person" means any state or local subdivision thereof, agency of such state or subdivision, corporation, or partnership that owns or operates or otherwise controls and provides children’s services or any individual who owns or operates or otherwise controls and provides such services.
SEC. 1043. NONSMOKING POLICY FOR CHILDREN’S SERVICES.
(a) PROHIBITION. After the date of the enactment of this Act, no person shall permit smoking within any indoor facility owned or leased or contracted for and utilized by such person for provision of routine or regular kindergarten, elementary, or secondary education or library services to children.
(b) ADDITIONAL PROHIBITION. After the date of the enactment of this Act, no person shall permit smoking within any indoor facility (or portion thereof) owned or leased or contracted for and utilized by such person of regular or routine health care or day care or early childhood development (Head Start) services to children or for the use of the employees of such person who provides such services.
(c) FEDERAL AGENCIES.
(1) KINDERGARTEN, ELEMENTARY, OR SECONDARY EDUCATION, OR LIBRARY SERVICES. After the date of the enactment of this Act, no Federal agency shall permit smoking within any indoor facility in the United States operated by such agency, directly or by contract, to provide routine or regular kindergarten, elementary, or secondary education or library services to children.
(e) SPECIAL WAIVER.
(1) IN GENERAL. On receipt of an application, the head of the Federal agency may grant a special waiver to a person described in subsection (a) who employs individuals who are members of a labor organization and provide children’s services pursuant to a collective bargaining agreement that —
(A) Took effect before the date of enactment of this Act; and
(B) Includes provisions relating to smoking privileges that are in violation of the requirements of this section.
(2) TERMINATION OF WAIVER. A special waiver granted under this subsection shall terminate on the earlier of —
(A) The first expiration date (after the date of enactment of this Act) of the collective bargaining agreement containing the provisions relating to smoking privileges; or
(B) The date that is 1 year after the date of the enactment of this Act.
(f) CIVIL PENALTIES.
(1) IN GENERAL. Any failure to comply with a prohibition in this section shall be a violation of this section and any person subject to such prohibition who commits such violation, or may be subject to an administrative compliance order, or both, as determined by the Secretary. Each day a violation continues shall constitute a separate violation.
Appendix G - Radon
EPA and other major national and international scientific organizations have concluded that radon is a human carcinogen and a serious public health risk. An individual’s risk of developing lung cancer from radon increases with the level of radon, the duration of exposure and the individual’s smoking habits. EPA estimates that 7,000 to 30,000 lung cancer deaths in the United States each year are attributed to radon.
Because many people spend much of their time at home, the home is likely to be the most significant source of radon exposure. For most school children and staff, the second largest contributor to their radon exposure is likely to be their school. As a result, EPA recommends that homes and school buildings be tested for radon.
Results from a National Survey of Radon Levels in Schools
A nationwide survey of radon levels in schools estimates that 19.3 percent of U.S. schools, nearly one in five, have at least one frequently occupied ground-contact room with short-term radon levels at or above the action level of 4 pCi/L (picocurie per Liter) -- the level at which EPA recommends mitigation. Approximately 73 percent of these schools will have only five or fewer schoolrooms with radon levels above the action level. The other 27 percent will have six or more such schoolrooms. If your building has a radon problem, it is unlikely that every room in your school will have an elevated radon level. However, testing all frequently occupied rooms that have contact with the ground is necessary to identify schoolrooms with elevated radon levels.
- Guidance for Radon Testing
- Guidance for Radon Mitigation
- Training for Testing and Mitigation
- Testing and Mitigation Costs
Guidance for Radon Testing
To assist schools with testing, helpful aids, such as a checklist of the testing procedure, are included in the document. Before initiating radon testing in your school however, contact your state Radon Office (see Appendix L: "Resources") for information on any state requirements concerning radon testing or for a copy of the document. Check IAQ Tools for Schools Publications for documents on radon in schools. See:
To reduce the health risk associated with radon, EPA recommends that officials test every school for elevated radon levels. Because the entry and movement of radon in buildings is difficult to predict, officials should test all frequently occupied schoolrooms that are in contact with the ground. If testing identifies schoolrooms with radon levels of 4 pCi/L or greater, officials should reduce the radon levels using an appropriate mitigation strategy.
Guidance for Radon Mitigation
If you identify a radon problem in your school, EPA developed guidance on radon mitigation entitled Reducing Radon in Schools – A Team Approach(EPA 402-R-94-008) that describes the recommended approach to radon mitigation in schools and provides an overview of the mitigation process to the IAQ Coordinator.
Guidance for Radon Prevention in Renovations and New Buildings
EPA’s document entitled Radon Prevention in Design and Construction of Schools and Other Large Buildings(EPA 625R-92-016) provides guidance for incorporating radon resistant and/or easy-to-mitigate features into the design of a new school building including design recommendations for heating, ventilation and air-conditioning (HVAC) systems. This guidance is useful to school personnel (e.g., school business officials) and architects involved with the new school construction. See Radon Publications and Resources.
Training for Testing and Mitigation
To develop public and private sector capabilities for radon testing and mitigation, EPA formed four Regional Radon Training Centers. These training centers offer courses on testing and mitigation in school buildings designed to simulate hands-on activities by having participants solve practical problems. Contact your state Radon Office for information on local training opportunities or state training requirements. See:
Testing and Mitigation Costs
Cost for radon testing in a typical school building ranges from $500 to $1,500. Costs for testing depend on the type of measurement device used, the size of the school and whether testing is performed in-house using school personnel or a measurement contractor.
If a radon problem is identified, the cost for radon mitigation typically ranges from $3,000 to $30,000 per school. The cost of mitigating a school depends on:
- The mitigation strategy
- The school building design
- The radon concentration in the school room(s)
- and the number of school rooms affected.
The appropriate mitigation strategy will consider the school building design and initial levels of radon. Mitigation costs at the high end of the cost range are often associated with a mitigation strategy involving the renovation of school HVAC systems. Although the cost is higher, this strategy has the added benefit of improving ventilation within a school building, which contributes to the overall improvement of IAQ.
Appendix H - Mold and Moisture
Molds can be found almost anywhere; they can grow on virtually any substance, providing moisture is present. Molds can grow on and within:
- and foods.
When excessive moisture accumulates in buildings or on building materials, mold growth will often occur, particularly if the moisture problem remains undiscovered or unaddressed. There is no practical way to eliminate all mold and mold spores in the indoor environment; the key to control indoor mold growth is to control moisture. If mold is discovered, clean it up immediately and remove excess water or moisture. In addition, maintaining the relative humidity between 30 and 60 percent will help control mold.
Molds produce tiny spores to reproduce. Mold spores waft through indoor and outdoor air continually. When mold spores land on a damp spot indoors, they may begin growing and digesting whatever they are growing on to survive.
There are many different kinds of mold. Molds can produce allergens, toxins and irritants. Molds can cause discoloration and odor problems, deteriorate building materials and lead to health problems — such as asthma episodes and allergic reactions — in susceptible individuals.
- Condensation, Relative Humidity and Vapor Pressure
- Taking Steps to Reduce Moisture and Mold
- Vapor Pressure-Dominated Mold Growth
- Surface Temperature-Dominated Mold Growth
- Mold Clean Up
- Identifying and Correcting Common Mold and Moisture Problems
Condensation, Relative Humidity and Vapor Pressure
Mold growth does not require the presence of standing water, leaks, or floods; mold can grow when the relative humidity of the air is high. Mold can also grow in damp areas such as:
- Unvented bathrooms and kitchens
- Crawl spaces
- Utility tunnels
- Locker rooms
- Wet foundations
- Leaky roof areas
- and damp basements.
Relative humidity and the factors that govern it are often misunderstood. This section discusses relative humidity and describes common moisture problems and their solutions.
Water enters buildings both as a liquid and as a gas (water vapor). Water is introduced intentionally in:
- Gym areas
- and art and utility areas
and accidentally by way of leaks and spills. Some of the water evaporates and joins the water vapor that is exhaled by building occupants. Water vapor also moves into the building through the ventilation system, through openings in the building shell, or directly through building materials.
The ability of air to hold water vapor decreases as the air temperature falls. If a unit of air contains half of the water vapor it can hold, it is said to be at 50 percent relative humidity (RH) or greater. The RH increases as the air cools and approaches saturation. When air contains all of the water vapor it can hold, it is at 100 percent RH or greater, and the water vapor condenses, changing from a gas to a liquid. The temperature at which condensation occurs is the "dew point."
Reaching 100 percent RH without changing the air temperature is possible by increasing the amount of water vapor in the air (the "absolute humidity" or "vapor pressure"). It is also possible to reach 100 percent RH without changing the amount of water vapor in the air, by lowering the air temperature to the "dew point."
The highest RH in a room is always next to the coldest surface. This is referred to as the "first condensing surface," as it will be the location where condensation happens first, if the relative humidity of the air next to the surface reaches 100 percent. Understanding this is important when trying to understand why mold is growing on one patch of wall or only along the wall-ceiling joint. The surface of the wall is likely to be cooler than the room air because of a gap in the insulation or because the wind is blowing through cracks in the exterior of the building.
Taking Steps to Reduce Moisture and Mold
Respond to water damage within 24–48 hours to prevent mold growth, which depends on moisture.
Mold growth can be reduced if the relative humidity near surfaces can be maintained below the dew point. This can be done by:
- Reducing the moisture content (vapor pressure) of the air;
- Increasing air movement at the surface; or
- Increasing the air temperature (either the general space temperature or the temperature at building surfaces).
Either vapor pressure or surface temperature can be the dominant factor in a mold problem. A vapor pressure-dominated mold problem may not respond well to increasing temperatures, whereas a surface temperature-dominated mold problem may not respond very well to increasing ventilation. Understanding which factor dominates will help in selecting an effective control strategy.
If the relative humidity near the middle of a room is fairly high (e.g., 50 percent at 70° F), mold or mildew problems in the room are likely to be vapor pressure dominated. If the relative humidity near the middle of a room is fairly low (e.g., 30 percent at 70° F), mold or mildew problems in the room are likely to be surface temperature dominated.
Vapor Pressure-Dominated Mold Growth
Vapor pressure-dominated mold growth can be reduced by using one or more of the following strategies:
- Use source control (e.g., direct venting of moisture-generating activities such as showers to the exterior).
- Dilute moisture-laden indoor air with outdoor air at a lower absolute humidity.
- Dehumidify the indoor air.
Note that dilution is only useful as a control strategy during heating periods, when cold outdoor air contains little total moisture. During cooling periods, outdoor air often contains as much moisture as indoor air.
Consider a school locker room that has mold on the ceiling. The locker room exhaust fan is broken, and the relative humidity in the room is 60 percent at 70° F. This is an example of a vapor pressure-dominated mold problem. In this case, increasing the surface temperature is probably not an effective way to correct the mold problem. A better strategy is to repair or replace the exhaust fan.
Surface Temperature-Dominated Mold Growth
Surface temperature-dominated mold growth can be reduced by increasing the surface temperature using one or more of the following approaches:
- Raise the temperature of the air near room surfaces.
- Raise the thermostat setting.
- Improve air circulation so that supply air is more effective at heating the room surfaces.
- Decrease the heat loss from room surfaces.
- Add insulation.
- Close cracks in the exterior wall to prevent "wind washing" (air that enters a wall at one exterior location and exits another exterior location without penetrating into the building).
Consider an old, leaky, poorly insulated school that has mold and mildew in the coldest corners of one classroom. The indoor relative humidity is low (30 percent). It is winter and cold air cannot hold much water vapor. Therefore, outdoor air entering through leaks in the building lowers the airborne moisture levels indoors. This is an example of a surface temperature-dominated mold problem. In this building, increasing the outdoor air ventilation rate is probably not an effective way to control interior mold and mildew. A better strategy would be to increase surface temperatures by insulating the exterior walls, thereby reducing relative humidity in the corners.
Mold Clean Up
Because moisture is the key to mold control, it is essential to clean up the mold AND get rid of excess water or moisture. If the excess water or moisture problem is not fixed, mold will most probably grow again, even if the area was completely cleaned. Clean hard surfaces with water and detergent and dry quickly and completely. Absorbent materials such as ceiling tiles may have to be discarded.
Note that mold can cause health effects such as allergic reactions; remediators should avoid exposing themselves and others to mold. Wear waterproof gloves during clean up; do not touch mold or moldy items with bare hands. Respiratory protection should be used in most remediation situations to prevent inhalation exposure to mold. Respiratory protection may not be necessary for small remediation jobs with little exposure potential. When in doubt consult a professional, experienced remediator. For more information on mold remediation refer to Appendix L: "Resources".
Identifying and Correcting Common Mold and Moisture Problems
Mold and Health Effects
Molds are a major source of indoor allergens. Molds can also trigger asthma. Even when dead or unable to grow, mold can cause health effects such as allergic reactions. The types and severity of health effects associated with exposure to mold depend, in part, on the type of mold present, and the extent of the occupants' exposure and existing sensitivities or allergies. Prompt and effective remediation of moisture problems is essential to minimize potential mold exposures and their potential health effects.
- Exterior Corners and Walls
- Set-Back Thermostats
- Air-Conditioned Spaces
- Thermal Bridges
- Concealed Condensation
Exterior Corners and Walls
The interior surfaces of exterior corners and behind furnishings such as chalk boards, file cabinets and desks next to outside walls are common locations for mold growth in heating climates. They tend to be closer to the outdoor temperature than other parts of the building surface for one or more of the following reasons:
- Poor indoor air circulation
- Wind washing
- Low insulation levels
- Greater surface area of heat loss
Sometimes mold growth can be reduced by removing obstructions to airflow (e.g., rearranging furniture). Buildings with forced air heating systems and/or room ceiling fans tend to have fewer mold problems than buildings with less air movement.
Set-back thermostats (programmable thermostats) are commonly used to reduce energy consumption during the heating season. Mold growth can occur when temperatures are lowered in buildings with high relative humidity. (Maintaining a room at too low a temperature can have the same effect as a set-back thermostat.) Mold can often be controlled in colder climates by increasing interior temperatures during heating periods. Unfortunately, this also increases energy consumption and reduces relative humidity in the breathing zone, which can create discomfort.
Mold problems can be as extensive in cooling climates as they are in heating climates. The same principles apply: either surfaces are too cold, moisture levels are too high, or both.
One common example of mold growth in cooling climates can be found in rooms where conditioned "cold" air blows against the interior surface of an exterior wall. This condition, which may be due to poor duct design, diffuser location, or diffuser performance, creates a cold spot at the interior finish surfaces, possibly allowing moisture to condense.
Possible solutions for this problem include:
- Eliminate the cold spots (i.e., elevate the temperature of the surface) by adjusting the diffusers or deflecting the air away from the condensing surface.
- Increase the room temperature to avoid overcooling. NOTE: During the cooling season, increasing temperature decreases energy consumption, though it could cause comfort problems.
Mold problems can also occur within the wall cavity, when outdoor air comes in contact with the cavity side of the cooled interior surface. It is a particular problem in rooms decorated with low maintenance interior finishes (e.g., impermeable wall covering such as vinyl wallpaper), which can trap moisture between the finish and the gypsum board. Mold growth can be rampant when these interior finishes are coupled with cold spots and exterior moisture.
A possible solution for this problem is to ensure that vapor barriers, facing sealants and insulation are properly specified, installed and maintained.
Localized cooling of surfaces commonly occurs as a result of "thermal bridges," elements of the building structure that are highly conductive of heat (e.g., steel studs in exterior frame walls, uninsulated window lintels and the edges of concrete floor slabs). Dust particles sometimes mark the locations of thermal bridges because dust tends to adhere to cold spots.
The use of insulating sheathings significantly reduces the impact of thermal bridges in building envelopes.
In winter, windows are typically the coldest surfaces in a room. The interior surface of a window is often the first condensing surface in a room.
Condensation on window surfaces has historically been controlled by using storm windows or "insulated glass" (e.g., double-glazed windows or selective surface gas-filled windows) to raise interior surface temperatures. In older building enclosures with less advanced glazing systems, visible condensation on the windows often alerted occupants to the need for ventilation to flush out interior moisture, so they knew to open the windows.
The advent of higher performance glazing systems has led to a greater number of moisture problems in heating climate building enclosures because the buildings can now be operated at higher interior vapor pressures (moisture levels) without visible surface condensation on windows.
The use of thermal insulation in wall cavities increases interior surface temperatures in heating climates, reducing the likelihood of interior surface mold and condensation. The use of thermal insulation without a properly installed vapor barrier, however, may increase moisture condensation within the wall cavity.
The first condensing surface in a wall cavity in a heating climate is typically the inner surface of the exterior sheathing.
Concealed condensation can be controlled by any or all of the following strategies:
- Reducing the entry of moisture into the wall cavities (e.g., by controlling entry and/or exit of moisture-laden air with a continuous vapor barrier).
- Raising the temperature of the first condensing surface.
- In heating-climate locations: Installing exterior insulation (assuming that no significant wind washing is occurring).
- In cooling-climate locations: Installing insulating sheathing to the interior of the wall framing and between the wall framing and the interior gypsum board.
Appendix I - Emissions from Motor Vehicles and Equipment
Emissions from gas or diesel-powered engines are a source of pollution for school grounds and buildings. Exhaust emissions come from mobile sources such as:
- School buses
- Delivery trucks and motorcycles
- Gasoline or diesel vehicles
- and equipment used for construction and grounds maintenance
"Mobile sources" is a term used to describe a wide variety of motor vehicles, engines and equipment that generate air pollution and that move, or can be moved, from place to place.
- Mobile sources at School
- Mobile Source Emissions
- Air Quality Issues
- Reducing Emissions
- Transportation Choices
- Other Mobile Sources on School Grounds
- Beneficial or Environmentally Friendly Landscaping
- Additional Resources
Mobile Sources at School
Some mobile sources at your school may include:
- School buses
- Delivery trucks
- Portable fuel containers
- equipment used for grounds maintenance:
- Snow blowers
- and other equipment
Special situations involving motor vehicles or equipment off school property may also contribute to the deterioration of the overall air quality near schools. These might include, for example, truck loading docks or construction sites.
Mobile Source Emissions
Mobile sources pollute the air through fuel combustion and fuel evaporation. These emissions contribute to air pollution nationwide and are the primary cause of air pollution in many areas. Mobile sources emit several significant air pollutants that affect human health and the environment, including:
- Carbon monoxide
- Nitrogen oxides
- and particulate matter.
For more information about these pollutants, see Appendix E: "Typical Indoor Air Pollutants".
In addition, mobile sources produce air toxins e.g.,
- Diesel exhaust
- and formaldehyde.
which are pollutants known or suspected to cause cancer or other serious health or environmental effects. Mobile sources are responsible for about half the air toxin emissions and risk nationwide.
Fine particulate matter (PM2.5) in diesel exhaust creates further health concerns. Recent studies suggest that children on or near school buses may be exposed to elevated levels of diesel exhaust. Children are especially susceptible to advance respiratory effects of PM2.5 because it can penetrate children’s narrower airways, reaching deep within the lungs where it is likely to be retained, and because children have higher rates of respiration per unit of their body weight than adults.
Air Quality Issues
Mobile source air pollutants can contribute to air quality issues at schools. With sufficient concentrations and duration, these pollutants may increase the chance of cancer or other serious health effects, such as asthma.
- Studies indicate that students can be exposed to high levels of diesel exhaust when they are inside school buses, near idling school buses and even inside schools (due to exhaust penetration from idling buses). Queuing of buses for pick-up and drop-off and periods of idling during the bus commute itself may be particular problems. Diesel exhaust can aggravate respiratory and cardiovascular disease and existing asthma. It can also cause acute respiratory symptoms, chronic bronchitis and decreased lung function.
- Outdoor emissions can infiltrate through windows and air intakes, resulting in student and staff exposure to pollutants and toxics.
- Chemicals and gasoline stored in school buildings can contribute to indoor air quality concerns, and equipment usage can result in exposure to air pollutants and toxics.
- Students, staff and vehicles sometimes congregate in the same place at the same time, which increases their exposure.
Successful reduction of vehicle and equipment emission involves a variety of approaches, some of which are no- or low-cost options. Those concerned about improving air quality in and around school can choose from options ranging from better vehicle technology and better transit options to cleaner fuels.
Schools can help reduce air pollution from mobile sources in a number of different ways. A comprehensive program might include:
- Bus retrofits and replacement
- Anti-idling policies
- Reduced power equipment usage
- Environmentally friendly transportation choices
- and equipment replacement.
Some other smart actions that reduce emissions include adopting driving practices that save gas and improve mileage, maintaining vehicles on a regular basis and using cleaner fuels.
Policies to minimize idling offer a smart, effective and immediate way to reduce emissions at little or no cost. In fact, reduced idling will save money in most cases because idling wastes fuel. The easiest way to reduce vehicle idling emissions is to "Just turn it off!" Today’s bus engines generally require only three to five minutes of warm-up time, even in cold weather. The problem of diesel fuel gelling in cold weather has been resolved by the creation of winter blends of fuel and fuel additives that better withstand colder temperatures.
Contrary to popular belief, idling actually does more damage to an engine than starting and stopping. Idling causes additional wear on an engine’s internal parts and, therefore, can increase maintenance costs and shorten the life of the engine.
Several States and local communities have already implemented anti-idling laws. These programs can reduce pollution, odor and noise, and save schools money by reducing engine wear and fuel consumption. Finally, anti-idling information is easy to incorporate into existing training and communications opportunities. For sample anti-idling policies and a sample memo to bus drivers, see Appendix B: "Developing Indoor Air Policies" in the IAQ Coordinator’s Guide.
Alternative transportation choices can also be beneficial for reducing emissions. For instance, "school-pooling" programs encourage carpools, bike partners, or "walking school buses" that reduce the number of vehicles on school grounds. Public transit buses may also be an appropriate option for some students or staff.
Other Mobile Sources on School Grounds
Since cars and trucks are not the only mobile sources on school grounds, attention should also be paid to lawn and garden equipment for reducing emissions. The two main ways to reduce emissions from such equipment are to replace existing equipment with cleaner options (e.g., manual, electric, or new 4-stroke, gasoline engines) and to reduce usage.
EPA adopted more stringent standards for gasoline-powered equipment, such as lawnmowers and string trimmers, which will lower hydrocarbon and nitrogen oxide emissions. Schools can reduce harmful emissions by ensuring their grounds maintenance equipment meets current standards. Like school bus retrofits and replacements, alternate equipment choices will be specific to your school’s situation. While manual and electric equipment are most beneficial because they do not produce emissions, these options are not always practical for large grounds.
Portable gasoline containers are another source of emissions on school grounds. Due to evaporation of gasoline, these cans pollute even when they are not being used, and especially when they are stored in a warm place. New, low-emission gasoline cans are designed for easy use and have a thicker lining in order to reduce fuel evaporation. They meet specified standards to minimize air pollution, including:
- Automatic closure
- Automatic shut-off
- Only one opening
- and limited permeation.
Many portable containers available nationwide meet all but the permeation standard. In addition, they are inexpensive (approximately $10), making them cost-effective solutions for reducing exposure to evaporated fuel.
Finally, proper maintenance and storage help decrease exposure to emissions from lawn and garden equipment. For example, lawn and garden equipment should be maintained regularly according to manufacturer guidelines to prevent problems that decrease efficiency and increase emissions. Keeping equipment tuned and in good condition is inexpensive and beneficial for minimizing emissions. In addition, fuels, chemicals and equipment should be stored appropriately in a well-ventilated, cool and dry space. For extended periods of storage (e.g., wintertime), gasoline should be emptied from equipment and containers or a stabilizer should be added to decrease evaporation.
Beneficial or Environmentally Friendly Landscaping
Ways to Reduce Emissions from Mobile Sources
- Diesel vehicle replacement and retrofit.
- Idling policy and training.
- "School-pooling" and transportation choices.
- Environmentally friendly landscaping.
- Low-emission gas cans.
- "Best Practices" for equipment maintenance and storage.
- What are good practices to use in areas where maintaining lawns is necessary?
- What are the benefits?
Beneficial landscaping refers to a suite of landscaping practices that yield environmental, economic and aesthetic benefits. These environmentally friendly practices include:
- Planting native species and low-maintenance turf grasses
- Reducing lawn area
- Strategic use of trees
- Integrated pest management (see Appendix K: "Integrated Pest Management")
- and optimizing water efficiency
Ultimately, beneficial landscaping produces a healthier environment and reduces air, water and soil pollution by minimizing emissions from:
- Power equipment
- and water.
In addition, beneficial landscaping is effective on any size of land. Emission reductions from beneficial landscaping alone can result in nearly 100 pounds less of smog-forming hydrocarbons and 10 pounds less of nitrogen oxide emissions per year per acre of lawn converted to natural landscaping due to reduced mowing. Hence, even small converted areas can contribute to notable reductions in emissions.
Grass can be replaced with:
- Native wildflowers
- and other native plants that do not require mowing and are already adapted to local conditions.
Trees, shrubs and native plants absorb water more efficiently than lawns and therefore minimize runoff and erosion. They can also decrease the amount of time you spend on weeding and watering and reduce the need for fertilizers and pesticides.
Beneficial landscaping can result in reduced building heating and cooling costs. For example, planting deciduous trees on the south side of a building provides shade, reducing heat absorbed by the building during the summer. This practice can decrease air conditioning costs by up to 20 percent. In the winter, deciduous trees lose their leaves, allowing the winter sun to warm the building. Planting conifers on the northwest side of a building helps to block northwest winds, reducing heating costs. Finally, planting trellis vines on the bare walls of buildings helps to keep these walls cooler by absorbing the sunlight. Planting trees around parking lots helps shade paved areas and further reduce sun-heating effects.
Finally, schools should use outdoor water efficiently by laying mulch in appropriate areas and installing efficient irrigation systems.
What are good practices to use in areas where maintaining lawns is necessary?
Cleanest Equipment Choices
- Reel mowers,
- Walk-behind mowers,
- Hedge trimmers,
- Hand-held leaf blowers
4-stroke gasoline engines:
- Available in almost all new lawn and garden equipment
Where lawns are necessary on school grounds, such as on play areas or sports fields, the following practices are best suited for reducing environmental impacts:
- Plant low-maintenance turf grasses that grow slowly and require less mowing.
- Leave grass clippings on lawns. This practice decreases the need for fertilizers and the amount of municipal solid waste entering landfills.
- Keep grass well maintained. Only one-third of the grass blade should be cut off at one time, and no more than one inch should be cut at one time.
What are the benefits?
Many advantages are associated with beneficial landscaping. Beneficial landscaping can be incorporated into science and environmental education. It creates hands-on learning experiences for students, while encouraging them to learn about natural habitats and take an interest in their surroundings.
Beneficial landscaping helps create a safer environment by reducing student and staff exposure to harmful emissions. It leads to fewer emissions from fossil fuel consumed during mowing, less fertilizer use and lower landscape maintenance labor and costs. Beneficial landscaping can also:
- Help decrease heating and cooling bills
- Reduce noise pollution (due to less mowing)
- Conserve water
- Reduce flooding and storm water management costs
- and decrease the strain on municipal waste collection and water treatment plants.
In addition, it can lead to cleaner water bodies for fishing, swimming and drinking due to reduced chemical use and erosion.
For more information about mobile sources on school grounds, please visit the EPA Clean School Bus USA Initiative. Clean School Bus USA provides information and resources to school districts on how to reduce pollution from school buses through retrofit, replacement and anti-idling programs. See National Clean Diesel Campaign - Clean School Bus.
Appendix J - Portable Classrooms
More than 385,000 portable classrooms, or relocatables, are used in approximately 36 percent of school districts across the nation, according to the National Center for Education Statistics (NCES). Portable classrooms are attractive to many school districts because they provide a quick and relatively inexpensive way to deal with unpredictable school enrollment numbers, limited building construction funds and the time lag between identification of need and the construction of new facilities. While portable classrooms are intended to provide flexibility to school districts, in reality, portable classrooms are seldom moved and often become permanent fixtures of the school.
Recent surges in student population fueled an explosion in the use of portable classrooms in many parts of the country. Health-related concerns associated with portable classrooms have arisen. Teachers in the new units frequently complain of chemical odors. In older units, odor problems are often associated with moldy classroom carpets. Both new and older units are often subject to complaints about poor ventilation and indoor air quality (IAQ).
- Indoor Air Quality and Portable Classrooms
- Recommendations for Schools Using Portables
- Additional Resources
Indoor Air Quality and Portable Classrooms
All school buildings use similar construction and furnishing materials, so the types of chemicals present in the indoor air are not likely to be different for portable versus permanent classrooms. However, pressed-wood products, which may contain higher concentrations of formaldehyde, are used more frequently in factory-built portable units than in buildings constructed on-site. As a result, concentrations of some airborne chemicals may be higher in new portable classrooms, especially if ventilation is reduced.
The most common problems with portable classrooms include:
- Poorly functioning ventilation systems that provide inadequate quantities of outside air;
- Poor acoustics due to loud heating and cooling systems;
- Chemical off-gassing from pressed wood and other high-emission materials, which may be of greater concern because of rapid occupancy and poor ventilation after construction;
- Water entry and mold growth; and
- Site pollution from nearby parking lots or loading areas.
Recommendations for Schools Using Portables
Although portable classrooms are often the lowest cost option for housing students, they range in quality. Care should be taken during specification and selection to ensure that the health of the students is not compromised on inexpensive, low quality designs. When districts specify a portable design, they typically create a term contract that other districts can use to purchase the same (or slightly different) design. This practice (often called "piggy-backing") can save a district valuable time and money on specifications and approvals, but it can also compound poor decisions made by the original procurement.
Like all school facilities, portable classrooms should contain appropriate building materials and properly designed ventilation systems to minimize the presence of indoor air pollutants. Commissioning and regular maintenance are also important to maintain the quality of the indoor environment.
The following steps can help schools maintain a healthy indoor environment in their portable classrooms:
Specifying New Portable Classrooms
- Specify the appropriate vapor barrier location for exterior wall construction, consistent with the climate where the classroom will be used.
- When specifying a new portable classroom, ensure that the heating, ventilation and air-conditioning (HVAC) system can:
- provide a minimum of 450 cfm of OUTSIDE air (based on 30 occupants at 15 cfm/occupant); and
- heat and cool this outdoor air at design outdoor air temperatures for the specific geographic location where each classroom is installed.
- Order an additional "outdoor air kit" since manufacturers do not include outdoor air intakes in their standard classroom models. Outdoor air intakes should not be located under portable units; these areas are typically not well ventilated and are prone to moisture, biological contaminants and other pollutants.
- Outdoor air should be supplied continuously when a classroom is occupied. In order to provide a continuous outdoor air supply, it is important to ensure that the HVAC thermostat fan switch is set in the "on" or continuous mode when occupied.
- Air filters are needed for protection of HVAC components and reduction of airborne dust, pollens and micro-organisms from recirculated and outdoor air streams. Air filters should have a spot rating between 35 and 80 percent or a Minimum Efficiency Rating Value (MERV) of between 8 and 13.
- If carpets are specified, use carpets that have been tested under the Carpet and Rug Institute’s Green Label Carpet Testing Program. Do not use carpet in entryways to classrooms with direct outdoor access. Supply waterproof mats and walk-off mats over carpeted entryways and other areas used for drying clothing and umbrellas.
- Locate classroom away from areas where vehicles idle or water accumulates after rains.
- Ensure that at least one supply air register and return air grille are located in each enclosed area. Also, make sure that building air intakes are located away from any exhaust outlet(s) or other contaminant sources.
- Specify operable windows to provide user-controlled ventilation when needed.
- Locate HVAC and air handler units as far away as possible from teaching areas to reduce noise.
- Specify minimal use of VOC emitting building materials.
- Install an awning over the portable’s entrance to help prevent rain and snow from blowing directly into classrooms.
- Specify complete documentation of operation and maintenance requirements.
- Prior to occupancy of any new portable units, operate HVAC systems at their maximum outdoor air intake rate continuously for several days. Start the "flush out" as soon as the HVAC system is operational, and continue after furniture installation. During this period, do not re-circulate return air. In humid climates, avoid introducing significant amounts of moisture during the flush out.
- Measure the amount of outdoor air entering the outdoor air intake of the HVAC unit to ensure it meets or exceeds the amount specified or 15 cfm per person, whichever is greater.
- Do not "bake out" the unit. "Bake out" is defined as increasing temperatures up to 100oF in order to "artificially age" building materials. Its effectiveness has not been proven and it may in fact damage parts of the HVAC system or building components.
- Establish and implement an Integrated Pest Management plan.
Operations and Maintenance
- Provide training on operation and maintenance of new HVAC equipment for appropriate staff. Instruct teachers and staff on proper use and settings of thermostat and ventilation controls.
- Train teachers how to minimize potential toxic emissions from the decorations and cleaning materials used in their classrooms. Develop and implement a "list of things to do before starting the class," including ensuring that the ventilation system is operating at least one hour before the class starts and watching for rust spots, wet spots and other signs of deterioration of infrastructure. Teachers should also be educated about the potential risks of turning off HVAC systems.
- Establish a regular and timely plan for testing, inspecting and performing specific maintenance tasks:
- Inspect roofs
- and carpet
- For more information about portable classrooms and recommendations for designing, constructing and renovating school facilities to maintain good IAQ, see EPA’s IAQ Design Tools for Schools.
- California Advisory on Relocatable and Renovated Classrooms (PDF) Exit
Appendix K - Integrated Pest Management
Integrated Pest Management (IPM) is a comprehensive approach to eliminating and preventing pest problems with an emphasis on reducing pest habitat and food sources. IPM is a safer and usually less costly option for effective pest management in the school community. A well-designed integrated pest management program is both effective and environmentally sensitive. IPM relies on a combination of:
- Low-impact pesticides;
- Comprehensive information about pests;
- Available and economical pest control methods; and
- Safety considerations for people, property and the environment.
Pests seek habitats that provide basic needs:
- and shelter.
Pest populations can be eliminated, prevented, or controlled by:
- Creating inhospitable pest environments;
- Removing basic elements that pests need for survival; or
- Blocking pest access into buildings.
Pests may also be managed by other methods such as traps and vacuums.
Managing Pests in Schools
Common pests found in schools (or on school grounds) include:
- Yellow jackets
- and termites
Although they can help control pests, pesticides need to be used carefully. Children may be more sensitive to pesticides than adults. In particular, young children may be particularly susceptible as they can encounter pesticides while crawling, exploring, or through hand-to-mouth activities.
Public concern about health and environmental risks associated with pesticides and other chemicals is increasing, particularly when children are involved. School administrators and others responsible for decisions about school-based pest control need to be aware of these risks and knowledgeable about safe alternatives.
There are many safe IPM practices for schools:
- Keep vegetation, shrubs and wood mulch at least one foot away from structures.
- Fill cracks and crevices in walls, floors and pavement.
- Empty and clean lockers and desks at least twice a year.
- Clean food-contaminated dishes, utensils and surfaces right away.
- Clean garbage cans and dumpsters at least bimonthly.
- Collect and properly dispose of litter or garbage at least once a week.
- Identify the problem or pest before taking action.
- Apply smaller amounts of fertilizers several times during the year (spring, summer and fall, for example) rather than one heavy application.
- Use spot applications or pesticides (if necessary) rather than area-wide applications.
- Store pesticides in well-ventilated buildings that are inaccessible to undesignated personnel or located offsite.
- Lock lids of bait boxes and place bait away from the runway of the box.
Establish an IPM Program for Your School
An efficient IPM program can and should be integrated with other school management activities, such as:
- Preventive maintenance
- Janitorial practices
- Occupant education
- and staff training
To establish an IPM program in your school:
Step 1: Develop an official IPM Policy Statement. In addition to showing the district’s support for an integrated approach to pest management, the statement should outline methods to:
- Educate and train staff
- Store pesticides
- Notify parents and school occupants of pesticide applications
- and keep accurate records
This policy statement can also act as a guide for the IPM manager while developing an IPM program.
Step 2: Designate specific roles for pest management personnel, school occupants and key decision-makers. For example:
- Encourage occupants to keep their areas clean
- Encourage parents to learn about IPM practices and follow them at home
- Designate a qualified person to be the pest manager
- and gain the support decision-makers who control the funds for IPM projects
Establish methods for good communication among these groups of people, and educate or train them in their respective roles.
Step 3: Set specific pest management objectives for each site. Tailor each objective to the site and situation. Examples of objectives for school buildings may include preserving the integrity of building structures or preventing interference with the learning environment of the students. Providing safe playing areas and best possible athletic surfaces are sample objectives for school grounds.
Step 4: Inspect site(s) to identify and estimate the extent of pest problems. After identifying potential pest habitats in buildings and on school grounds, develop plans to modify the habitats (for example, exclusion, repair and sanitation). Establish a monitoring program that involves routine inspections to track the success of the habitat modifications and to estimate the size of the pest population.
Step 5: Set thresholds for taking action. These thresholds are the levels of pest populations or site environmental conditions that require remedial action. It is important to consider sensitive individuals when setting thresholds.
Step 6: Apply IPM strategies to control pests when you reach an action threshold or to prevent pest problems. These strategies may include redesigning and repairing structures, establishing watering and mowing practices and storing pesticides in well ventilated areas. Refer to the IPM Checklist for a list of possible strategies for indoor and outdoor sites as well as information on safe pesticide use and storage.
Step 7: Evaluate the results of your IPM practices to determine if pest management objectives are being met. Keep written records of all aspects of the program, including records for state and local regulations.
Evaluating the Costs
IPM programs may actually cost less in the long-term than a conventional pest control program that relies solely on the use of pesticides. Although the long-term labor costs for IPM may be higher than those for conventional pesticide treatments, the labor costs are often offset by reduced expenditures for materials.
Whether an IPM program raises or lowers costs depends in part on the nature of the current housekeeping, maintenance and pest management operations. The costs of implementing an IPM program also depend on whether the pest management services are contracted, performed in-house, or a combination of both. To fit the IPM program into the existing budgetary framework, school administrators must consider what additional and redistributed expenditures are involved. As with any program, insufficient resources will jeopardize the success of an IPM program.
IPM provides schools with an economical, environmentally friendly alternative to control and prevent pest problems. Schools should tailor IPM programs to meet their specific needs and set appropriate objectives and thresholds to help them implement a successful pest management program.
For additional information on IPM, see Appendix L: "Resources."
Appendix L - Resources
This appendix lists organizations with information or services related to indoor air quality (IAQ). In addition, the appendix includes a section on IAQ-related publications. Following is a list of the subsections contained in this appendix.
Please Note: Reference herein to any specific commercial products, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government and shall not be used for advertising or product endorsement purposes.
- Federal Agencies with Major Indoor Air Responsibilities for Public and Commercial Buildings
- EPA Regional Offices
- Other Federal Agencies
- State and Local Agencies
- Professional and Standards Setting Organizations
- Product Manufacturer Associations
- Building Service Associations
- Employee Unions
- Environmental/Health/Consumer Organizations
- Multiple Chemical Sensitivity-Related Organizations
- Organizations Offering Training on Indoor Air Quality
- Other EPA Contacts and Programs of Interest
Federal Agencies With Major Indoor Air Responsibilities For Public and Commercial Buildings
U.S. Environmental Protection Agency (EPA)
The U.S. Environmental Protection Agency conducts a non-regulatory IAQ program that emphasizes:
- information dissemination
- technical guidance
- and training
EPA issues regulations and carries out other activities that affect IAQ under the laws for pesticides, toxic substances and drinking water.
Office of Air and Radiation/Office of Radiation and Indoor Air/Indoor Environments Division
1200 Pennsylvania Avenue, #6609J
Washington, D.C. 20460
View Frequent Questions / Ask a Question
Search frequently asked questions or submit your own question or comment in our Frequent Questions Database. In addition to questions and answers relating to indoor environments, you may use this database to find information on any of our topic areas; for example, IAQ topics with their descriptions, for example:
- IAQ Tools for Schools
- Smoke-free Homes
- IAQ Design Tools for Schools
- and General Indoor Air Quality Issues
You can also use this database to subscribe to any new information or updated information relating to any of the topics that may be posted on our website.
EPA Office of Transportation and Air Quality
National Vehicle and Fuel Emissions Laboratory
Phone: (734) 214-4333 (voicemail) or (734) 214-4462
Description: Advances clean fuels and technology to reconcile the transportation sector with the environment and promote more livable communities. Sponsors a voluntary diesel retrofit program.
EPA Regional Offices
Address inquiries to IAQ staff in the EPA regional offices go to Find Information about Local Radon Zones and State Contact Information, click on your state or EPA Region.
Other Federal Agencies
Occupational Safety and Health Administration (OSHA)
National Institute for Occupational Safety and Health (NIOSH)
to identify and mitigate workplace problems.
Centers for Disease Control & Prevention
National Heart, Lung, & Blood Institute Information Center
U.S. Department of Energy
State and Local Agencies
Your questions and concerns about indoor air problems can frequently be answered most readily by the government agencies in your state or locality. Responsibilities for IAQ issues are usually divided among many different agencies. You will often find that calling or writing the agencies responsible for health or air quality control is the best way to start getting information from your state or local government. For state agency contacts, go to - Find Information about Local Radon Zones and State Contact Information click on your state or EPA Region.
Professional and Standards Setting Organizations
The following links exit the site Exit
Air and Waste Management Association
Air-Conditioning and Refrigeration Institute
American Industrial Hygiene Association
American Society for Testing and Materials
National Association of School Nurses
Product Manufacturer Associations
The following links exit the site Exit
Adhesive and Sealant Council
Carpet and Rug Institute
Consumer Specialty Products Association
Electric Power Research Institute
Gas Technology Institute
Manufacturers of Emissions Controls Association
National Paint and Coatings Association
North American Insulation Manufacturers’ Association
National Service Center for Environmental Publications (NSCEP):
Items marked *** are available for order from NIOSH Publications Dissemination
Items marked **** are available for order from the U.S. General Accounting Office
Indoor Air Quality
General IAQ Information
Indoor Air Quality Tools for Schools Companion Documents
Biological Contaminants (Mold, Pests, Etc.)
Polychlorinated Biphenyls (PCBs)
Building Management, Investigation, and Remediation
New Building Design
Standards and Guidelines
Appendix M - Glossary and Acronyms
Any information gathered using this Action Kit is for the benefit and use of schools and school districts. EPA does not require retention or submission of any information gathered, and EPA has no regulatory or enforcement authority regarding general indoor air quality in schools. This Action Kit has been reviewed in accordance with EPA's policies. Information provides the current scientific and technical understanding of the issues presented. Following the advice given will not necessarily provide complete protection in all situations or against all hazards that may be caused by indoor air pollution.
Mention of any trade names or commercial products does not constitute endorsement or recommendation for use.
Please note the following as you prepare to use this Action Kit:
- This Action Kit is not intended as a substitute for appropriate emergency action in a hazardous situation that may be immediately threatening to life or safety.
- Modification of building functions, equipment, or structure to remedy air quality complaints may create other indoor air quality problems and may impact life-safety systems and energy use. A thorough understanding of all the factors that interact to create indoor air quality problems can help avoid this undesirable outcome. Consult with professionals as necessary.
- In the event that medical records are used while evaluating an IAQ problem, maintain confidentiality.
This Action Kit contains public information that may be produced or modified in whole or in part without permission. If the Action Kit or its contents are reproduced or modified, EPA would appreciate knowing how it is used. Please write to: IAQ Tools for Schools Program, Indoor Environments Division, U.S. Environmental Protection Agency, 1200 Pennsylvania Ave., NW, MC-6609J, Washington, DC 20460
For more information, see Indoor Air Quality
|U.S. Environmental Protection Agency
Indoor Environments Division, 6609J
1200 Pennsylvania Ave., NW
Washington, DC 20460
|American Federation of Teachers Exit
555 New Jersey Ave., N.W.
Washington, DC 20001
|Association of School Business Officials Exit
11401 North Shore Drive
Reston, VA 22090
|National Education Association Exit
1201 16th Street, N.W.
Washington, DC 20036-3290
|National Parent Teachers Association Exit
330 North Wabash Avenue, Suite 2100
Chicago, IL 60611-3690
|American Lung Association Exit
New York, NY 10019