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Indoor Environmental Air Quality

To escape the harsh winter wind, beating rain, or hot summer sun, we seek the refuge of the indoors. Yet how safe is our indoor environment ? Studies performed by the Environmental Protection Agency (EPA) have shown that indoor levels of air pollutants may be two to five times higher than outdoor levels.[i] This is particularly striking considering that Minnesotans spend approximately 90 percent of their time indoors.[ii] We spend so much of our time indoors, it is logical that we would want an indoor environment that is healthy and comfortable.

Indoor environmental quality (IEQ) encompasses everything in the indoor setting including air quality, ventilation, thermal comfort, noise and lighting . IEQ is of concern because it affects both our physical and mental health. An estimated 15 to 100 billion dollars of our nation’s annual medical bills can be attributed to indoor air pollution.[iii] Although people have varying sensitivities to poor indoor air quality, symptoms may include headache, fatigue, sinus congestion, coughing, sneezing, dizziness, nausea, and irritation of the eyes, nose, throat, and skin. Additionally, indoor air pollutants may provoke allergies, asthma, chemical hypersensitivity or building-related illness. “The estimated potential annual nationwide benefits of improvements in IEQ include the following: a 10 to 30 percent reduction in acute respiratory infections and allergy and asthma symptoms and a 20 to 50 percent reduction in acute non-specific health symptoms.”[iv] Just as all buildings have universal access features, the indoor environment of every building should be safe for all people.

Ensuring a healthy indoor environment can improve productivity and concentration, reduce absenteeism, and promote well-being. In a study sited by the EPA in “Indoor Air Quality and Student Performance,” experimenters periodically placed 20-year-old used carpet on racks behind a screen, so office occupants had no way of knowing when the carpet was present. The occupants were subjected to a variety of tests including typing, memory, logical reasoning, and arithmetic skills. The subjects performed two to six percent better on all tasks when the carpet was not present.[v] To create a healthy, comfortable setting for working and living, there are three basic approaches our institutions should take. The first is to eliminate the sources of air pollutants, which is the most effective and efficient way to reduce the concentration of indoor air pollutants. All the materials going into the structure need critical evaluation. The second approach is to isolate air pollution sources. Areas of the building that emit pollutants, such as copy rooms, should be ventilated outdoors, thereby preventing the pollutants from spreading throughout the building. The third approach is to provide proper air ventilation.

Some of these measures may present higher costs up front; however, long term saving in terms of health and productivity need to be considered. Annual cost savings and productivity gains of $30 billion to $170 billion are the estimated nation-wide benefits generated from improved IEQ.[vi] Moreover, providing good IEQ is favorable to learning and working; it is in line with our institution’s core mission – education and well-being.

Our institutions already have an Indoor Air Quality Program that addresses causes and problems associated with indoor air pollution; therefore, the next step is to step establish goals by which we can achieve a healthy indoor environment . Our first goal is to provide an indoor air setting that is healthy for occupants, enhances well-being, performance, and productivity. This goal addresses many different components of indoor air quality (IAQ):

• Minimizing occupant exposure to radon is very important, because radon is a radioactive gas. It is the second leading cause of lung cancer. Radon occurs naturally in the soil, but it can seep into and concentrate in buildings. Given our location in a high radon potential area, built-in passive radon-resistant construction features should be incorporated into the structure. It is much cheaper to mitigate high radon when passive features are already in place.
• Tobacco smoking would be banned from the building and within 30 feet of any entrances, windows or air intakes. This can be easily implemented since we already have a no smoking indoor policy and most people understand the dangers of tobacco smoking and the effects of second-hand smoke.
• Mold and microbial growth can also cause significant indoor air quality problems, and therefore need to be addressed. Controlling the relative humidity can help reduce the growth of mold and mildew. Additionally, using materials that discourage microbial growth can also help combat this problem.
• Proper air circulation can help reduce the concentration of indoor air pollutants and improve comfort levels. For improved health and air quality it is important that occupants receive the appropriate amount of outdoor air. Increased ventilation can be achieved without significant increases in energy costs, if the appropriate heating, ventilation and air conditioning (HVAC) system is used and ventilation is designed from an integrated, whole building perspective.

Our second goal addresses IEQ from a source perspective. The goal is to minimize off-gassing during the construction of a building. Reducing construction debris and choosing low off-gassing materials will reduce adverse health affects on the installer. It is also important that all absorptive materials are kept protected from moisture damage during construction. After construction is complete, it is necessary to totally flush out the structure with outdoor air to remove and dilute pollutants.

Once construction is complete, the amount of off-gassing during the usage phase should be kept to a minimum. Low-emitting materials should be used in applications wherever possible. These materials must at least meet the standards for volatile organic compounds (VOCs).

• Volatile organic compounds refer to a variety of different organic compounds, including benzene, chloroform, p-Dichlorobenzene, formaldehyde and tetrachloroethylene. They are the “principal component in atmospheric reactions that form ozone and other photochemical oxidants.”[vii] Although there are no Minnesota or federal standards for VOCs, they cause a variety of negative health effects from dizziness, irritation, nervous system damage, developmental effects, to cancer. The impact of VOCs depends on the amount inhaled, the extent of exposure and individual susceptibility.

Studies by the U.S. Environmental Protection Agency (EPA) have revealed that a majority of indoor air pollutants are VOCs released from building materials and equipment.[viii] When constructing a new office building for a large accounting firm in Atlanta, the consultants Environmental Design International, paid attention to detail and made careful material selections. The result was a 50 to 70 percent lower concentration of various VOCs and a reduction in absenteeism by six to ten percent.[ix]

• Formaldehyde levels should not exceed 0.05 parts per million. Formaldehyde is hard to detect, yet some people are sensitive to levels as low as 0.03 parts per million. Formaldehyde may be prominent indoor air pollutant, because it can be found in permanent press fabrics, plywood, particleboard, glues, paints, sealants , plastics and carpets. It poses health threats including headaches, fatigue, moodiness, irritation of mucus membranes, respiratory problems, and cancer. By using materials with no or low formaldehyde, these risks can be greatly decreased.

The fourth goal is to provide occupants with an indoor environment that is pleasing to their senses. To achieve this goal, the areas of indoor air temperature and relative humidity, lighting , views and noise are addressed. The indoor setting affects people’s perception of IAQ. When the air temperature and relative humidity are at the low end of the acceptable ranges, IAQ is perceived to be better. People are better able to concentrate, less stressed and more productive when they are in a comfortable environment. A setting with a view of the outdoors, appropriate lighting and minimal vibrations is more conducive to working. “Lighting characteristics influence the quality of vision and can have psychological influences on mood and on perceptions about the pleasantness of a space.”[x] Additionally, a study by the California Energy commission found that “office workers performed 10 to 25 percent better on tests of mental function and memory recall when they had the best possible view versus those with no view.”[xi] The quality of the view is affected by the size of the window and by the greater vegetation content.

In line with the goal to provide a comfortable environment for occupants, it is important that occupants can alter the indoor setting to fit personal preference. Our fifth goal is to design a structure that allows occupants control of the mechanical and structural systems at work in the space. Providing occupants with access to thermostats and humidistats, control of lighting systems, and the option of opening a window grants, them the ability to modify personal workspace.

The sixth goal is to implement proper scientific technology so that the space can be constantly monitored for health conditions. To ensure occupant health and comfort, permanent air quality monitoring systems are necessary to provide feedback on the performance of the ventilation systems. Thermostats, humidistats, and carbon monoxide and carbon dioxide monitoring systems should be installed.

Typical indoor levels of carbon dioxide are not a serious health concern; however, they are indicative of high levels of other pollutants. In a study of 800 students in Europe, scores on concentration tests were lower when carbon dioxide levels increased.[xii] High levels of carbon dioxide imply low exchange rates of outdoor air; therefore, levels of other pollutants are also likely to be high.

In addition to improving ventilation and reducing the sources of indoor air pollutants, it is important that pollutants do not spread throughout the building. The mechanical system should be designed with an effective air ventilation system, thereby preventing cross-contamination of rooms. Rooms with high levels of air pollutants, such as copy/print rooms and chemical storage rooms, should be depressurized relative to surrounding areas, and the air should be exhausted outdoors. Limiting the spread of indoor pollutants will minimize occupant exposure to the negative air quality impacts.

By implementing these goals, we will successfully create an indoor environment that is safe, healthy, and comfortable. Occupants would have the pleasure of knowing that they are in a place that serves not only as a refuge from the harsh Minnesota elements but also as a sanctuary from harmful air pollutants.