What's all the fuss about "indoor" air pollution? I always thought "outdoor" air pollution was the main problem?
Scientific evidence indicates the air within homes and other buildings can be two to five times more polluted than the outdoor air, and in some cases 1,000 times more polluted. Today people are spending nearly 90% of their time indoors, a great increase as opposed to twenty years ago. Thus, the "dose", i.e. the concentration of pollutants multiplied by the time in that environment, is typically greater indoors than outdoors. This results in a greater health risk due to exposure to air pollution indoors than outdoors.
Are some individuals at greater risk to indoor air pollution than others?
Yes, individuals who spend the longest periods of time indoors are often those most susceptible to the adverse effects of indoor air pollution. Such groups include babies, the elderly, the infirm or bedridden, and those with chronic illnesses, such as respiratory or cardiovascular disease.
What causes indoor air quality problems?
Two main items:
1. Pollutant sources: building materials and furnishings; biologicals; products for household cleaning, personal care, or hobbies; central heating and cooling systems and humidification devices; pesticides; oil, gas, kerosene, or wood combustion sources.
2. Poor ventilation: If too little outdoor air enters a building, pollutants can accumulate to levels that can pose health and discomfort problems. Indoor air quality began to decline in the 1970's after the "energy crisis" prompted the building of "tight" houses and office buildings. Spaces around doors and windows where outside air might previously have leaked through are now often sealed by caulking and weather-stripping . The introduction of fresh "makeup" air through air handling systems many times is reduced or even eliminated to save the cost of the energy to heat or cool this fresh air. Indoor air pollutants can not easily escape these tightly constructed buildings.
How does indoor air pollution affect your health?
Health effects can include irritation of the eyes, nose, and throat, headaches,dizziness, fatigue, and allergy-type symptoms. Usually these symptoms are short-term, and disappear when the person is away from the source. More serious symptoms such as asthma, hypersensitivity pneumonitis, and humidifier fever can also affect some individuals after exposure to certain indoor air pollutants. There is a tremendous amount of variation in the sensitivity among individuals to indoor air pollutants. Some people may never experience any symptoms while others may truly suffer. Because many symptoms may be difficult to distinguish from viruses, or allergies (which are quite common in Texas), care must betaken to determine if symptoms are worse while in a particular building versus outside, or whether they dissipate when a person is away for several days.
How does one go about improving indoor air quality in a home or office building?
Indoor air quality problems within a building can generally be resolved by providing sufficient fresh outside air and by eliminating major sources of contamination within the building.
How can a homeowner get an on-site indoor air survey?
A homeowner has many avenues to get on-site help to identify indoor air quality problems. There are trained investigators that can do on-site indoor air surveys. Look in your local Yellow Pages phone book under categories such as "industrial hygiene consultants," "environmental consultants," or "testing or environmental laboratories." Look for those that advertise "indoor air surveys" or "sick building syndrome." Ask what certifications the firm holds and how much they charge to conduct a survey. Call several and pick the one you are most comfortable with.
