Indoor Air Quality (IAQ) deals with the content of interior air that could affect health and comfort of building occupants. The IAQ may be compromised by microbial contaminants (mold, bacteria), chemicals (such as carbon monoxide, radon), allergens, or any mass or energy stressor that can induce health effects. Recent findings have demonstrated that indoor air is often more polluted than outdoor air (albeit with different pollutants) although this has not changed the common understanding of air pollution. In fact, indoor air is often a greater health hazard than the corresponding outdoor setting. Using ventilation to dilute contaminants, filtration, and source control are the primary methods for improving indoor air quality in most buildings.
Techniques for analyzing IAQ include collection of air samples, collection of samples on building surfaces and computer modeling of air flow inside buildings. The resulting samples can be analyzed for mold, bacteria, chemicals or other stressors. These investigations can lead to an understanding of the sources of the contaminants and ultimately to strategies for removing the unwanted elements from the air1. In addition, the Environmental Protection Agency (EPA), which lists poor indoor air quality as the fourth-largest environmental threat to our country, has created multiple documents, guidelines, and standards to help address indoor air quality the various influences that affect it.
Your Home – (information from the EPA website: http://www.epa.gov/iaq/homes) Indoor pollution sources that release gases or particles into the air are the primary cause of indoor air quality problems in homes. Inadequate ventilation can increase indoor pollutant levels by not bringing in enough outdoor air to dilute emissions from indoor sources and by not carrying indoor air pollutants out of the home. High temperature and humidity levels can also increase concentrations of some pollutants.
There are many sources of indoor air pollution in any home. These include combustion sources such as oil, gas, kerosene, coal, wood, and tobacco products; building materials and furnishings as diverse as deteriorated, asbestos-containing insulation, wet or damp carpet, and cabinetry or furniture made of certain pressed wood products; products for household cleaning and maintenance, personal care, or hobbies; central heating and cooling systems and humidification devices; and outdoor sources such as radon, pesticides, and outdoor air pollution.
The relative importance of any single source depends on how much of a given pollutant it emits and how hazardous those emissions are. In some cases, factors such as how old the source is and whether it is properly maintained are significant. For example, an improperly adjusted gas stove can emit significantly more carbon monoxide than one that is properly adjusted.
Some sources, such as building materials, furnishings, and household products like air fresheners, release pollutants more or less continuously. Other sources, related to activities carried out in the home, release pollutants intermittently. These include smoking, the use of unvented or malfunctioning stoves, furnaces, or space heaters, the use of ozone generating air cleaners/purifiers, the use of solvents in cleaning and hobby activities, the use of paint strippers in redecorating activities, and the use of cleaning products and pesticides in housekeeping. High pollutant concentrations can remain in the air for long periods after some of these activities.
If too little outdoor air enters a home, pollutants can accumulate to levels that can pose health and comfort problems. Unless they are built with special mechanical means of ventilation, homes that are designed and constructed to minimize the amount of outdoor air that can “leak” into and out of the home may have higher pollutant levels than other homes. However, because some weather conditions can drastically reduce the amount of outdoor air that enters a home, pollutants can build up even in homes that are normally considered “leaky.”
Green Buildings – (information from the EPA website: http://www.epa.gov/iaq/greenbuilding/) Do your buildings create a healthy environment for their occupants? The building industry is increasingly focused on making its buildings greener, which includes using healthier, less polluting and more resource-efficient practices. Indoor environmental quality (IEQ) refers to the quality of the air and environment inside buildings, based on pollutant concentrations and conditions that can affect the health, comfort and performance of occupants — including temperature, relative humidity, light, sound and other factors. Good IEQ is an essential component of any building, especially a green building.
Creating a better indoor environment can help building owners, managers, occupants, architects and builders to minimize or eliminate the negative health effects, liability, bad publicity, and costly renovations and repairs often associated with IEQ problems. Improving IEQ involves designing, constructing, commissioning, operating, and maintaining buildings in ways that reduce pollution sources and remove indoor pollutants while ensuring that fresh air is continually supplied and properly circulated.
The EPA is tackling the problems associated with maintaining building IEQ through a collection of cutting-edge voluntary and informational programs. EPA’s Indoor Environments program promotes the use of integrated, whole building approaches to protect occupant health while saving energy and money. The program focuses on major building types including offices and institutional buildings, schools, homes, as well as major cross-cutting indoor air quality issues like mold and moisture.
1- Indoor_air_quality. (n.d.). Wikipedia, the free encyclopedia. Retrieved September 09, 2007, from Reference.com website: http://www.reference.com/browse/wiki/Indoor_air_quality