In approximately 500 indoor air quality investigations in the last decade, the National Institute for Occupational Safety and Health (NIOSH) found that the primary sources of indoor air quality problems are:
- Inadequate ventilation 52%
- Contamination from inside the building 16%
- Contamination from outside the building 10%
- Microbial Contamination 5%
- Contamination from building fabric 4%
- Unknown sources 13%
Common indoor air contaminants include the following:
1. Acetic Acid
Sources: X-ray development equipment, silicone caulking compounds.
2. Carbon Dioxide
Sources: Unvented gas and kerosene appliances, improperly vented devices, processes or operations which produce combustion products, human respiration.
3. Carbon Monoxide
Sources: Tobacco smoke, fossil-fuel engine exhausts, improperly vented fossil-fuel appliances.
Sources: Off-gassing from urea formaldehyde foam insulation, plywood, particle board, and paneling; carpeting and fabric; glues and adhesives; and combustion products including tobacco smoke.
5. Nitrogen Oxides
Sources: Combustion products from gas furnaces and appliances; tobacco smoke, welding, and gas and diesel-engine exhausts.
Sources: Copy machines, electrostatic air cleaners, electrical arcing, smog.
Sources: Ground beneath buildings, building materials, and groundwater.
8. Volatile Organic Compounds (VOC’s) – Volatile organic compounds include trichloroethylene, benzene, toluene, methyl ethyl ketone, alcohols, methacrylates, acrolein, polycyclic aromatic hydrocarbons, and pesticides.
Sources: Paints, cleaning compounds, moth-balls, glues, photocopiers, “spirit” duplicators, signature machines, silicone caulking materials, insecticides, herbicides, combustion products, asphalt, gasoline vapors, tobacco smoke, dried out floor drains, cosmetics and other personal products.
9. Miscellaneous Inorganic Gases – Includes ammonia, hydrogen sulfide, sulfur dioxide.
Sources: Microfilm equipment, window cleaners, acid drain cleaners, combustion products, tobacco smoke, blue-print equipment.
Sources: Insulation and other building materials such as floor tiles, dry wall compounds, reinforced plaster.
11. Synthetic Fibers
Sources: Fibrous glass and mineral wool.
12. Tobacco Smoke
Sources: Cigars, cigarettes, pipe tobacco.
13. Microorganisms and Other Biological Contaminants (Microbials)
Includes viruses, fungi, mold, bacteria, nematodes, amoeba, pollen, dander, and mites (for more information on mold, refer to this section of our website).
Clay Point Associates, Inc. is available to assist facility owners/managers and homeowners with a wide variety of indoor air quality (IAQ) complaints. An initial IAQ investigation typically involves interviews with building owners/occupants, a review of existing records of complaints, review of Heating, Ventilation and Air Conditioning (HVAC) systems and a walkthrough of the building.