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Indoor Air Quality (IAQ)

Should I have the air ducts in my home cleaned?

  • The key to mold control is moisture control.
  • If mold is a problem in your home, you should clean up the mold promptly and fix the water problem.
  • It is important to dry water-damaged areas and items within 24-48 hours to prevent mold growth.

EPA's Should You Have the Air Ducts in Your Home Cleaned? provides an excerpt on duct cleaning and mold which follows, please review the entire document for additional information on duct cleaning and mold.

You should consider having the air ducts in your home cleaned if:

There is substantial visible mold growth inside hard surface (e.g., sheet metal) ducts or on other components of your heating and cooling system. There are several important points to understand concerning mold detection in heating and cooling systems:

  • Many sections of your heating and cooling system may not be accessible for a visible inspection, so ask the service provider to show you any mold they say exists.
  • You should be aware that although a substance may look like mold, a positive determination of whether it is mold or not can be made only by an expert and may require laboratory analysis for final confirmation.  For about 50, some microbiology laboratories can tell you whether a sample sent to them on a clear strip of sticky household tape is mold or simply a substance that resembles it.
  • If you have insulated air ducts and the insulation gets wet or moldy it cannot be effectively cleaned and should be removed and replaced.
  • If the conditions causing the mold growth in the first place are not corrected, mold growth will recur.

Read the publication, "A Brief Guide to Mold, Moisture, and Your Home"

Una Breve Guía para el Moho, la Humedad y su Hogar está disponible en el formato PDF https://19january2021snapshot.epa.gov/cai/una-breve-guia-para-el-moho-la-humedad-y-su-hogar  Documento de la agencia EPA número 402-K-03-008.

For more information on mold, see our website at www.epa.gov/mold