Bacterial Amplification and In-Place Carpet Drying: Implications for Category 1 Water Intrusion Restoration



The study described in this article investigated whether in-place carpet drying processes resulted in bacterial amplification following water intrusion from a clean water source (category 1) in a residential indoor environment. Bacterial amplification was examined after wetting a 10-year old carpet and pad that had no history of water intrusion. Three test areas were extracted and dried using industry-recommended procedures for in-place drying and compared to a control area that was not extracted or dried. Results from carpet, pad, and subsurface dust demonstrated that bacterial amplification occurred in all test areas. CFUs of bacteria per gram of carpet surface dust and subsurface dust prior to water intrusion were lower than levels in subsurface dust after in-place drying. The authors’ study contributes to information regarding the restoration of water-based carpet damage by professional water damage restoration companies, building maintenance personnel, and housekeeping managers. Results suggest that the appropriate response time for carpet pad salvage is considerably shorter than the current industry recommendation of 72 hours.




Posted with permission from the Journal of Environmental Health, May 2012, (Volume 74, Number 9, pp. 8-14), a publication of the National Environmental Health Association,




Jim Holland, REA, RestCon Environmental
John Banta, CAIH, RestCon Environmental
Boni Passmore, PhD, RCAnalytical
Mark Ayers, CAC, RestCon Environmental

Sean P. Abbott, PhD, Natural Link Mold Lab, Inc.

Eugene C. Cole, DrPH, Brigham Young University