Carpet Cleaning: Steam Vapor the Clear Winner in Fighting Mold in Carpet

Properly cleaning an office or home requires care under normal circumstances, but regular cleaning is nothing compared with the effort that must be expended when a major event occurs. Fires, floods and other natural disasters require cleaning methods that can successfully tackle removing smoke, mold and other germ-laden deposits.

How to best handle carpet cleaning following a major event, in this case a water pipe that had burst, was the impetus behind a recent study sponsored by The Carpet and Rug Institute. The study, which was partially funded by the U.S. Department of Housing and Urban Development, evaluated three carpet cleaning methods and their ability to clean moldy carpet. The goal was to evaluate the growth of fungi and its removal over time using the selected methods: high-flow, hot-water extraction; hot water and detergent; and steam vapor.

“We were very pleased that the Thermal Accelerated Nano Crystal Sanitation (TANCS®) steam vapor technology was included as one of the study methods,” says Rick Hoverson, principal with Advanced Vapor Technologies (AVT). “We believe steam vapor cleaning is an excellent choice, and the results of the study validated that belief.”

The study was conducted by the University of St. Louis School of Public Health in St. Louis, MO. Essentially, the team simulated an average home’s carpet that was located in a flooded basement. Researchers embedded 60 carpet samples with heat-treated house dust, followed by further embedding of the soil and ‘wearing’ the carpet with a hexapod tumbler device to simulate traffic conditions. The carpet was then wetted and inoculated with a liquid suspension of Cladosporium sphaerospermum, a common mold spore, prior to placing the carpet over a water-saturated foam pad. The carpet was then incubated for 24 hours, seven days and 30 days, and was cleaned after each time period using the three selected cleaning methods.

Researchers found that fungal loading increased from approximately 1,300 colony forming units (CFU) per square foot after 24 hours to a maximum of approximately 9,200 CFU per square foot after seven days. The 30 day CFU count was still greatly elevated but slightly less than the peak after seven days.

The results achieved with the three cleaning methods varied greatly. Steam vapor with TANCS® technology emerged as the superior alternative as evidenced by the results in the shortest and longest incubation times:

According to the study abstract: “Significant differences were found among all three methods for removal of fungi over time. Steam was significantly better than the other two methods with 99% efficiency in removal of Cladosporium sphaerospermum from wetted carpet after 24 hours and 30 days incubation time, with 92% efficiency after 7 days. The other two methods had declining efficiencies of fungal removal over time, from a maximum of 82% and 81% at 24 hours down to 60% and 43% at 30 days for detergent and high-flow, hot water extraction, respectively. The net effect of the mold management study demonstrates that while steam has a nearly constant fungal removal rate, the detergency and high-flow, hot water methods decline in efficiency with increasing fungal growth.”

“The steam vapor system with TANCS® technology generates high-temperature, very low-moisture steam vapor, which is directed into the carpet surface at approximately 104 C,” says Hoverson. “Studies have shown that the TANCS® technology forms nano crystals within ordinary tap water. When this water transforms into super-heated steam vapor, these crystals are energized as well. It is our belief that these nano crystals assist in disrupting the microbes’ cell membrane, which in turn allows the moist heat to more quickly disable or coagulate cell proteins. Once this is accomplished, the mold organism dies. It’s a chemical-free, cost-effective and non-consumptive technology that is easy to use and that works successfully.”

AVT’s steam vapor system with TANCS® is a relative newcomer to the world of carpet cleaning. The product’s capabilities – in this case significantly reducing mold after the carpet has been wet for 24 hours or more – offers one proven answer for how to best clean carpet when disaster strikes.