Mold Removal with Steam Vapor

Study validates new technology

by Allen P. Rathey, InstructionLink/JanTrain, Inc.

Whether as a result of a natural disaster -- such as Hurricane Katrina or the torrential downpours that plagued the Midwestern United States last summer -- or something more mundane, such as a broken water pipe or leaky roof, at some point virtually every cleaning professional will be faced with the challenge posed by wet, molding carpet. When it comes to how best to handle this challenge, there can be a lot more than just repeat business at stake.

According to the U.S. Environmental Protection Agency (EPA), “Mold can cause allergic reactions, asthma, and other respiratory problems; nasal stuffiness; eye irritation; wheezing; or skin irritation. Some people, such as those with serious allergies to molds, may have more severe reactions, including fever and shortness of breath. Meanwhile, people with chronic lung illnesses, such as obstructive lung disease, may develop mold infections in their lungs.”

Similar findings are cited by other major health organizations worldwide, including the American Lung Association. Some specialty environmental and remediation firms, such as Envirochex in its report “Mold & Health,” take the potential health dangers of mold even further:

“There are an estimated 100 species of mold known to cause infections in humans, and immune suppressed individuals are especially at risk. Aspergillosis is a common fungal infection requiring hospitalization in the United States. Other fungi can infect hair, skin, and nails. Many species of mold produce toxic metabolites called mycotoxins, which are believed to be most prevalent in spores (both living and dead spore). Mycotoxins are of special concern since some may present a [significant] hazard to humans … including nerve damage, organ damage, and cancer.”

So while experts agree that mold poses potentially severe health hazards to humans, the true extent of the danger remains unknown. What is certain, however, is that wet carpet can be a harbor for mold, and professional carpet cleaners and remediation services need to know how best to remove it to keep their customers satisfied and safe.

Not All Options are Solutions
When it comes to carpet, there are several mold-remediation methods available:

Throw it out. While expedient, this may not be a welcome suggestion to customers operating under budget constraints (and what customers are not these days?), especially for larger carpeted areas and when the wet carpet is not worn out.

Wet and dry vacuuming. This option is feasible, but only if the carpet was relatively clean, just slightly wet and likely to dry quickly -- and is in areas with low humidity and adequate air flow to assure rapid drying. All mold needs is a moist environment and nourishment to flourish. A wet, even slightly soiled carpet provides the right breeding ground for bacteria and mold that vacuuming alone cannot remove.

Also, dry mold spores can become airborne during the vacuuming process, further contaminating the environment and aggravating human airways. And if the vacuum isn’t emptied and adequately cleaned, it can end up not only smelling foul but playing host to the mold itself.

Hot-water extraction with detergent. Still often erroneously referred to as “steam cleaning” (despite the fact that the water falls far short of the 212-degree minimum necessary to boil water, let alone create steam), hot-water extraction has been used for years by professionals to rejuvenate carpet.

Yet Rick Hoverson, president of Advanced Vapor Technologies, provides insight into the conundrum this method presents for mold removal from carpet. “Hot-water extractors use chemicals pumped in with water, and even expensive, top-of-the-line extractors only get 85 percent to 90 percent of the water out [of the carpet] that they put into it. So, they leave at least 10 percent of the water behind. This means they also leave 10 percent of the chemical behind. The chemical residue can attract dirt and organic soil -- the nutrients that, in the wet environment, encourage mold. Also, often the chemicals themselves contain toxins that may be potentially harmful.”

Steam vapor. Originating in Europe, this increasingly popular method of cleaning turns water from a liquid into a low-moisture, “dry” steam vapor hot enough to loosen soil and kill bacteria and mold. Because so little water actually enters the carpet, it does not exacerbate the saturation problem. (“Extractors generally use water defined in gallons per minute; steam vapor defines it as quarts per hour,” Hoverson said.) And the absence of chemicals means no sticky residue to further aid and abet mold growth. Other bonuses of the steam-vapor cleaning method include:

• Faster overall process, factoring drying time.
• Environmentally friendly -- as only clean water can be!
• Less labor intensive (heat does much of the work).
• Low water usage (carpet dries faster with less chance for further mold growth).
• Economic -- no expensive chemicals.
• In-depth soil, mold and microbial remediation due to steam’s penetrating properties.

Vapor Proof
It’s easy to claim that steam vapor because of its inherent heat and penetrating power is effective for killing and removing mold from wet carpet, but now there is concrete, independent research to prove it.

A recent study sponsored by the Carpet and Rug Institute (CRI), funded in part by the U.S. Department of Housing and Urban Development (HUD), and conducted by researchers at the University of St. Louis School of Public Health in St. Louis, MO, compared the effectiveness of three cleaning methods in removing mold from wet carpet: high-flow hot water extraction, hot water with detergent, and steam vapor with Thermal Accelerated Nano Crystal Sanitation (TANCS®) technology.

For the study, researchers simulated an average home’s carpet that might be found in a flooded basement, and embedded house dust into 60 carpet samples, grinding the dirt in using a special tumbler to simulate one year of carpet wear from real-life traffic conditions. Next, the researchers wetted and inoculated the carpet with Cladosporium sphaerospermum (a common mold spore) and placed the carpet on top of a water-logged foam pad. To avoid cross contamination, the samples were housed in separate compartments with at least 75 percent relative humidity. Then the researchers waited, leaving the carpet to incubate for 24 hours, for seven days, and for 30 days. At the end of each time period, the samples were cleaned using the three selected cleaning methods.The steam vapor with TANCS technology emerged the clear winner, as the abstract of the study relates: “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
percent efficiency in removal of Cladosporium sphaerospermum from wetted carpet after 24 hours and 30 days incubation time, with 92 percent efficiency after seven days. The other two methods had declining efficiencies of fungal removal over time, from a maximum of 82 percent and 81 percent at 24 hours, down to 60 percent and 43 percent 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.”

TANCS Uniqueness
The steam vapor system used in this study was supplied by Advanced Vapor Technologies and was equipped with TANCS water treatment technology.

“TANCS is a proprietary water treatment system that works to charge the water to make it more efficient in delivering latent heat in the steam vapor to the proteins inside the organisms it is applied to,” said Hoverson.

He then explained the technology in more basic terms, starting with a quick lesson on the nature of mold.

“Molds and fungi use spores to reproduce,” he said. “Spores are encased, like an egg or a tough vegetable seed, and the airborne, encased spores that land on a surface can remain viable for a long time. Because spores are so hardy, it is clear you need something capable of destroying them.”

This is where TANCS comes in. Studies have shown that TANCS technology forms nano crystals within tap water. When the water is transformed into steam vapor, the crystals become energized, which are thought to weaken the cell membrane or casing.

“Using TANCS treated water for steam generation, bacteria, spores, and viruses become more susceptible to heat,” Hoverson explained. “TANCS weakens the outer spore shell so the heat penetrates it more quickly, delivering a lethal thermal shock to the cell proteins so they die. And, we do all this using just plain old tap water.”

When steam vapor is proven to be more efficient, there is every reason for carpet care/remediation professionals to include it in their mold removal arsenals.

Reprinted from Floor Care Professional, January 2008