Indicators on Air Quality You Need To Know

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“Indoor air quality” refers to the quality of the air in a home, school, office, or other building environment. The potential impact of indoor air quality on human health nationally can be noteworthy for several reasons: Americans, on average, spend approximately 90 percent of their time indoors,1 where the concentrations of some pollutants are often 2 to 5 times higher than typical outdoor concentrations.2 People who are often most susceptible to the adverse effects of pollution (e.g., the very young, older adults, people with cardiovascular or respiratory disease) tend to spend even more time indoors.3 Indoor concentrations of some pollutants have increased in recent decades due to such factors as energy-efficient building construction (when it lacks sufficient mechanical ventilation to ensure adequate air exchange) and increased use of synthetic building materials, furnishings, personal care products, pesticides, and household cleaners.


Substances of natural origin such as radon, pet dander, and mold. Biological agents such as molds. Pesticides, lead, and asbestos. Ozone (from some air cleaners). Various volatile organic compounds from a variety of products and materials. Most pollutants affecting indoor air quality come from sources inside buildings, although some originate outdoors.


Other substances in indoor air are of natural origin, such as radon, mold, and pet dander. Outdoor sources: Outdoor air pollutants can enter buildings through open doors, open windows, ventilation systems, and cracks in structures. Some pollutants come indoors through building foundations. For instance, radon forms in the ground as naturally occurring uranium in rocks and soils decays.

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In areas with contaminated ground water or soils, volatile chemicals can enter buildings through the same process.Volatile chemicals in water supplies can also enter indoor air when building occupants use the water (e.g., during showering, cooking).Finally, when people enter buildings, they can inadvertently bring in soils and dusts on their shoes and clothing from the outdoors, along with pollutants that adhere to those particles.


The air exchange rate is affected by the design, construction, and operating parameters of buildings and is ultimately a function of infiltration (air that flows into structures through openings, joints, and cracks in walls, floors, and ceilings and around windows and doors), natural ventilation (air that flows through opened windows and doors), and mechanical ventilation (air that is forced indoors or vented outdoors by ventilation devices, such as fans or air handling systems) (Indoor Air Pollution).


Weather conditions influence find out whether building occupants keep windows open or closed and whether they operate air conditioners, humidifiers, or heaters, all of which can affect indoor air quality. Certain climatic conditions can increase the potential for indoor moisture and mold growth if not controlled by adequate ventilation or air conditioning - Indoor Air Pollution.


Headaches, dizziness, and fatigue. Respiratory diseases, heart disease, and cancer. The link between some common indoor air pollutants (e.g., radon, particle pollution, carbon monoxide, Legionella bacterium) and health effects is very well established. Radon is a known human carcinogen and is the second leading cause of lung cancer.4, 5 Carbon monoxide is look at this web-site toxic, and short-term exposure to elevated carbon monoxide levels in indoor settings can be lethal.6 Episodes of Legionnaires' disease, a form of pneumonia caused by exposure to the Legionella bacterium, have been associated with buildings with poorly maintained air conditioning or heating systems.7, 8 Numerous indoor air pollutants—dust mites, mold, pet dander, environmental tobacco smoke, cockroach allergens, particulate matter, and others—are “asthma triggers,” meaning that some asthmatics might experience asthma attacks following exposure.9 While adverse health effects have been attributed to some specific pollutants, the scientific understanding of some indoor air quality issues continues to evolve.One example is “sick building syndrome,” which occurs when building occupants experience similar symptoms after entering a particular building, with symptoms diminishing or disappearing after they leave the building.

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Though her explanation much is known about the broad range of indoor air quality issues and associated health effects, currently only two national indicators of indoor air quality are available based on long-term and quality data: Radon and Serum Cotinine (a measure of exposure to tobacco smoke). For various reasons, ROE indicators could not be developed for other indoor air quality issues - air quality.


This does not mean that nothing is known about the broad range of indoor air quality issues and associated health effects. Rather, information and data on these issues can be gathered from government publications and the scientific literature. These data are not presented as ROE indicators since they are not representative on a national scale or do not reflect an issue over a sufficiently long time period.


Environmental Protection Agency. 1989. Report to Congress on indoor air quality: Volume 2. EPA/400/1-89/001C. Washington, DC. [2] U.S. Environmental Protection Agency. 1987. The total exposure assessment methodology (TEAM) study: Summary and analysis. EPA/600/6-87/002a. Washington, DC. [3] U.S. Environmental Protection Agency. 1997. Exposure factors handbook volume 3: Activity factors. EPA/600/P-95/002Fa. Washington, DC.




Environmental Protection Agency. 2003. EPA assessment of risks from radon in homes. EPA/402/R-03/003. Washington, DC. [5] National Research Council. 1999. Health effects of exposure to indoor radon: biological effects of ionizing radiation (BEIR), report VI. Washington, DC: National Academies Press. [6] Raub, J (air quality).A., M. Mathieu-Nolf, N.B. Hampson, and S.R. Thom.

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Carbon monoxide poisoning—a public health perspective. Toxicology 145:1-14. [7] Allan, T., et al. 2001. Outbreak of Legionnaires' disease among automotive plant workers—Ohio, 2001. MMWR 50(18):357-359. [8] Fields, B.S., R.F. Benson, and R.E. Besser. 2002. Legionella and Legionnaires' disease: 25 years of investigation. Clin. Microbiol. Rev. 15(3):506-526. [9] Institute of Medicine.


Clearing the air: Asthma and indoor air exposures. Washington, DC: National Academies Press. [10] U.S. Environmental Protection Agency. 2003. Indoor air quality and student performance. EPA/402/K-03/006. Washington, DC.