- THE MAGAZINE
It's a Natural
Mold is an organic decomposer found everywhere in nature. However, health problems and damage to structure can arise when mold is allowed to multiply indoors - basically, any place that moist air can condense on a cold surface. If unattended for as little as 48 hours, mold is likely to grow. And while some porous materials, such as dry wall, carpet and insulation must be removed, semi-porous materials like concrete and wood can be cleaned without damaging the structure.
Conventional cleaning methods require sanding and scraping the mold from the wood's surface, a tedious and generally unpleasant process. Dry ice blasting, on the other hand, completely removes spores from the wood in less time and with less effort.
How Dry Ice Blasting Works
The process is non-toxic, non-corrosive, non-abrasive and non-conductive - using thermal shock to clean in most applications. However, it uses kinetic energy when blasting on wood. As the dry ice (-78.5 C) blasts against the mold-infested wood, it removes the top 1/16 inch of wood, and the mold along with it.
Chemical biocides don't always eliminate the allergens (called metabolites) that are responsible for the allergic reactions associated with the mold. Also, biocides are typically harmful to those using them (they are not recommended for routine use by the EPA or OSHA). Sandblasting is too abrasive to the underlying surface. Water and steam blasting do not provide a thorough clean, and there is a greater chance of mold regeneration due to moisture. And while soda blasting provides an effective clean, it leaves behind a rather messy secondary waste stream, an issue that doesn't come up with dry ice sublimation.
Clean Across the Country Tom Monacelli of Advanced Indoor Air in New Jersey uses dry ice blasting. "Before, crews would spend about six days cleaning a mold-infested attic in a 1,500 square foot home by manually crawling into the space to sand and scrape the moldy wood," he said. "Then we'd apply a biocide and an anti-microbial coating to seal it.
"With dry ice blasting, we can clean the same size attic in two days with half the amount of manpower. And no need for the biocide or the encapsulation...our work consistently passes the industrial hygienist's post-remediation verification tests," Monacelli said.
The approach is particularly effective where engineered roof or floor joists and decking are impregnated with mold spores. In a single pass, their crews can effectively and efficiently remove mold from multiple right-angled surfaces - historically a backbreaking and time-consuming process. The dry ice blasting system also provides remediation crews with access to tight areas that may otherwise be unreachable, e.g. 3-to-4-inch gaps in framing and rim joists above concrete-stem walls.
No Madness in the Method
Dry ice blasting's ability to clean mold-infested surfaces thoroughly and efficiently is making it a leading method for mold remediators around the county - equipment costs being mitigated with the increased amount of mold remediation projects a firm can perform. Very cool.