Adopted by the MIAQC Board of Directors on August 5, 2004

There is growing scientific evidence that the air within homes and other buildings can be significantly more polluted than the outdoor air. Since Americans spend approximately 90 percent of their time indoors, the risks to health from exposures to indoor pollution can be much greater than exposures to outdoor pollution. (See MIAQC Policy Statement on the Health Basis for MIAQC Recommendations for additional information on the health risks of indoor pollution)

Two of the primary causes of indoor air quality problems are 1) indoor pollutants that release gases or particles into the air, and 2) excessive moisture/humidity levels that can lead to biological contamination or mechanical/structural systems failures.

The most effective strategy to improve indoor air quality is to exercise source control. Source control is a process of first attempting to eliminate, then reduce or manage the individual sources of pollution and their emissions.


Eliminating the contaminant from the indoor environment is the primary means to prevent the risk of adverse health effect from exposure to the contaminant.


Reduce the pollutant source when elimination of the pollutant is not possible.


When the presence of the contaminant serves an identified use or purpose, building occupants and managers should manage the pollutant source:

  • Determine first if other, safer products, appliances or systems are available (see EPA)
  • Carefully consider the value of the product, appliance or system with the risk of its use
  • Periodically review HVAC and plumbing systems for appropriate application
  • Conduct periodic Operations and Maintenance of HVAC and plumbing systems in accordance with design intent
  • Strictly adhere to all manufacturer’s specifications for use, installation and maintenance of a product or appliance.
  • Strictly adhere to the label instructions for application of chemical products used indoors (Read the MSDS sheets for any chemical product used or stored indoors.)
  • Properly store and ventilate, or dispose of material to limit exposures
  • Schedule use of contaminants to limit exposure to building occupants



MIAQC Policy Statements

EPA – IAQ Fact Sheets