Dry ice blasting is rapidly becoming a preferred method of cleaning wood in the mold remediation industry due to its unparalleled results and timesavings when compared to the usual methods of sanding or scraping with a wire brush. Mold remediators are using dry ice blasting to reduce their remediation time by as much as 60 to 80 percent per project. This innovative cleaning process is gain-ing momentum in the fi eld of Mold Reme-diation because of its ability to thoroughly remove mold spores from salvageable wood. In addition, dry ice blasting benefi ts the mold remediator because it grants access to tight and confi ned spaces, such as attics or crawl spaces, where mold can be found decaying wood beams and trusses.

Salvaging Damaged WoodDry Ice Blasting for Mold Removal

By Tina Moore and Gary Gilman

Mold is an organic decomposer and it can be found everywhere; it even aids in the break down of the leaves in the fall. In fact, the world would be a messy place without mold. Mold’s problematic issues arise when it is allowed to multiply indoors. It can cause health problems, damage to building materials and struc-tural damage to wood. Mold problems are found in basically anyplace that moist air can condense on a cold surface. If mois-ture problems are left unattended for 48 hours or longer, mold is likely to grow and it will be necessary to implement a removal plan.

Mold that can be found on many porous materials, such as dry wall, car-pet and insulation, must be remediated through complete removal. These are materials that cannot be salvaged and will have to be disposed of; however, semi-po-rous materials, such as concrete and wood, can remain in the building and be cleaned. Conventional cleaning methods require the mold remediator to manually sand, scrape or wire brush the mold from the wood’s surface. This can be a tedious and generally unpleasant process to endure. Conversely, dry ice blasting results in complete spore removal from the wood in less time, and with less effort than any other method. Dry ice blasting allows the remediator to save contaminated wood, which is a valuable cost savings tool for remediators and their clients, since the

price of wood is drastically rising across the country. SteamMaster, in Vail, CO began utiliz-ing dry ice blasting in their mold remedia-tion division two years ago, having had researched dry ice blasting approximately 15 years earlier for possible use in fire restorations and industrial cleaning. Since they purchased their Cold Jet dry ice blasting system, the firm has successfully completed over 30 dry ice blasting projects. Most of the company’s mold remediation projects, which employ the use of this cutting edge technology, include removing mold from attic and crawl space sheathing, trusses and framing. SteamMaster finds the use of dry ice blasting 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 that would be cumbersome and time-consuming to access with sanding or scraping. The dry ice blasting system also provides their remediation crews with ac-cess to clean tight areas that may other-wise be unreachable, such as three to four inch gaps in framing and rim joists above concrete-stem walls. Traditionally, dry ice blasting uses thermal shock effect to clean specific produc-tion applications. The process is non-toxic,

Salvaging Damaged Wood Dry Ice Blasting for Mold Removal (Continued)

the operator. The dry ice is at a tempera-ture of -78.5°C, and as it blasts against the contaminant it causes it to shrink and lose its adhesion from the substrate. The tem-perature of the underlying surface is warm in comparison to the dry ice, which causes the dry ice to convert back into its natural state, carbon dioxide gas. The gaseous car-bon dioxide’s volume is so much greater than its volume as a solid that it expands

non-corrosive, non-abrasive and non-conductive. So, as it accelerates dry ice particles into a pressurized air streamto impact the surface being cleaned, it will not interrupt any electric compounds or wiring and it will not cause toxic harm to

behind the contaminant and causes it to lift from the substrate. The process does not generate any secondary waste stream because the carbon dioxide sublimates into the atmosphere. With regards to mold remediation, dry

ice blasting will typically remove about 1/32 of the wood’s surface being cleaned, so it is using kinetic energy to clean. This abrasion is enough to ef-fectively remove the mold spores, but not enough to alter the struc-tural integrity of the contaminated area. Since there is no secondary waste stream to attend to, the only thing left to do is vacuum the residual mold and wood that was removed from the blasting. Tom Mona-celli of Advanced Indoor Air, a mold remediator in New Jersey, uses the Cold Jet dry ice blasting system and said he “couldn’t be

happier” with the process. It has reduced his cleaning time by at least 60% in most cases. Prior to his machine purchase, his remediation 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 would then apply a biocide to kill any remaining mold, followed by an anti

microbial coating to seal the surface. With dry ice blasting he can clean the same size attic in two days with half the amount of manpower. In addition, he no longer needs to apply the biocide or the encapsulation, as the dry ice blasting completely removes the mold from the contaminated surface. He goes on to say, “We cleaned six town-houses, with a total of 18 moldy wooden structures. Each and every one of those wooden structures passed the Industrial Hygienist’s post remediation verification test.” The allergens in mold are not always eliminated with a biocide, rendering dead mold as allergenic and in need of removal. Metabolites, which are responsible for the allergic reactions associated with mold, are found in mold spores. They seep into the wood and are not always killed with the biocide. In addition, these biocides are typically registered pesticides and are potentially harmful to those using them. The EPA and OSHA do not recommend routine use of bleach or other biocides in mold remediation. To eliminate the al-lergenic properties associated with mold, it is necessary to entirely remove it from the contaminated surface. With any mold remediation project, it is crucial to take the necessary precautions with regards to the safety. Proper personal protective equipment should be worn and the area being treated will need to be properly sealed off so that the mold spores do not fly into other near-by areas. Specific to the dry ice blasting method of mold remediation, it is ideal to have the blasting unit in an area separate from the contaminated attic or crawl space. Extreme caution must be employed to manage oxygen levels in confined areas, so this is done in order to reduce the amount of carbon dioxide gas buildup in the air.

The crews must also vent fresh air into the work area and exhaust the build up of carbon dioxide gas to the outside. A negative air flow environment with HEPA filtration is often used in tight and confined attics and crawl spaces to ensure operator safety. As an added protection, the crew should wear helmets connected to a breather box by a supplied air line. Dry ice blasting may be better suited for mold remediation than any other type of blasting, such as sand blasting, water blasting or soda blasting. Sandblasting is far too abrasive to the underlying surface, while dry ice blasting will not cause sig-nificant structural damage to the contami-nated wood. Water and steam blasting do not provide a thorough clean in com-parison to dry ice blasting, and there is a greater chance of mold regeneration due to the water vapor and moisture component. Soda blasting is an effective, although messy, cleaning method with regards to mold remediation. However, the main draw back with soda blasting applies to the other blasting methods as well. It leaves behind a secondary waste stream to be attended to. With dry ice blasting, the carbon dioxide gas sublimates into the atmosphere after it impacts the surface being cleaned, leaving no additional waste streams.

Tina Moore is a marketing assistant with Cold Jet, LLC. Gary Gilman is president and founder of SteamMaster Carpet Cleaning And Restoration Inc. For more information, go to www.coldjet.com or call 513-831-3211.

Salvaging Damaged Wood Dry Ice Blasting for Mold Removal (Continued)

Specific to the dry ice blasting method of mold remediation, it is ideal to have the blasting unit in an area separate from the contaminated attic or crawl space. Ex-treme caution must be employed to man-age oxygen levels in confined areas, so this is done in order to reduce the amount of carbon dioxide gas buildup in the air. The crews must also vent fresh air into the work area. Dry ice blasting is a fresh approach to mold remediation and is currently being used by many remediators in various parts of the country. Its ability to clean mold-in-fested surfaces, like wood, thoroughly and efficiently is an irresistible alternative to sanding and scraping. While there are costs associated with buying the equip-ment, these costs are outweighed by the benefits generated as a result of utiliz-ing dry ice blasting in mold remediation projects. Generally speaking, these ingenious blasting systems have increased the amount of mold remediation projects a firm can perform. So, due to the drastic reduction in cleaning time implemented by dry ice blasting, these firms can dramatically boost their revenues as well.