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.


Molds grow on almost any organic substance, as long as moisture and oxygen are present. When excessive moisture accumulates in buildings or on building materials, mold growth will often occur, particularly if the moisture problem remains undiscovered or unaddressed. It is impossible to eliminate all mold and mold spores in the indoor environment. However, mold growth can be controlled indoors by controlling moisture indoors.

REHS has developed guidelines for the cleanup of moldy surfaces and materials. These guidelines are based upon recommendations presented by the EPA. The EPA does not regulate mold or mold spores in the indoor air. Sampling for mold has no regulatory standard, so therefore, REHS usually does not sample for mold.

The key to mold control is moisture control. Solve moisture problems before they become mold problems!

Remediation guidelines and additional sources for information can be found at the sites listed below. As always, please contact REHS with specific concerns or questions.

If you have an Indoor Air Quality issue, please complete a Maintenance Request here