By Bob Baker

The title of this month's column may have raised two questions in the minds of most readers. First, "Should I have any interest in Radon? My business is heating ventilating and air-conditioning." Second, you may have wondered if radon has anything to do with mold. According to reports I have gotten recently from the field, the answer to both questions is, yes! In order to continue to provide a professional level of service to your customers, you may have to learn some of the basic facts about radon and especially the methods used to remove it from homes and other buildings. That is because excessive mold growth can be the result of a radon mitigation project. And, you as the HVAC professional, are the logical person to solve the problem that has been created. This is an example of the increasing complexity in our business that shows up as we learn more about all the factors that must be controlled in order to provide our customers the quality of indoor environment that they are coming to expect.

Radon

As most of us know, radon is a colorless and odorless radioactive gas that is released from soil in many parts of the US. If the air we breathe most of the day contains high concentrations of radon, we are at increased risk for cancer and respiratory ailments. Even in areas where radon output from soil is high, there is little danger outdoors because natural air currents dilute the concentration before it can build to a danger level. However, concentrations can build up inside of buildings in areas where there is high soil release.

Since the risks associated with high levels of radon have become more widely known, an entire industry has grown up around the problem. Testing services identify problem buildings, which have excessive concentrations or are at risk. Radon consultants analyze problem buildings and formulate plans and strategies for eliminating the risk. Mitigation contractors install systems that remove the excessive concentrations. Although the exact design of a mitigation system will depend on the design and construction of the building, most such systems have the potential to affect pressure relationships between the building and the outdoors, and within the building structure itself. As we have previously discussed, changes in building pressure can cause moisture laden air to reach areas where it can condense and support mold growth.

Cure Leads To Problem

In one case that was reported, a forced air radon abatement system was installed to remove an accumulation of radon from the sealed crawl space of a home. This routed the excess radon through a conduit that vented through the roof. Although the air flow volume was low (below 100 CFM), it was sufficient to create a negative pressure between the crawl space and the outside. Since the crawl space was sealed, air to equalize the pressure could not come from outside. Instead, air was drawn from unsealed openings to the wall cavities of the home. This placed wall cavities under negative pressure and they in turn drew hot moist air from the attic space. When this air hit the cold internal wall surfaces, a lot of water condensed out on those surfaces.

Mold City

The result, aptly named "mold city" by one observer, led to a massive indoor air quality problem. Residents in the home became sensitized to mold and eventually moved to a hotel while the problem was being corrected. Initially, the role of the radon mitigation system in triggering the problem was not identified. This led to extra expense and delays in identifying the source of the mold growth that eventually spread throughout the building. Obviously, this was a building that was on the edge. It took only a small change to lead to a disaster. There may be many other such homes or other buildings where a minor change to the building dynamics can lead to a failure of the building system. For this reason, is important to treat each building as a complete system.

Some HVAC contractors, having recognized this are branching out into related areas. Many have formed departments that offer duct cleaning and/or indoor air quality advisory services. Others actually offer radon abatement services. Other contractors who do not wish to take on the complexity of different departments are forming close relationships with specialists in these areas. That way, they can offer their customers a comprehensive solution. The lesson here is that consumers are becoming better educated, aware of their health and comfort needs, and more demanding of those that they choose to fill their needs. Contractors who want to attract and retain those "new" customers will be those capable of understanding the building as a complete system. Businesses that are only capable of "repairing HVAC equipment", will be at a disadvantage.

Mr. Baker's field of expertise is the control of contamination in air-conditioning and ventilating systems by mold, mildew and bacteria. He writes and speaks frequently about the efficacy, legal risks, and regulatory issues involved in various control strategies. He serves on ASHRAE Technical Committee TC 2.3, TC 2.4, TC 9.8, and Sampling of Airborne Particulate Concentration in Commercial and Residential Buildings GPC 17P. He also serves as a member of ASTM D22.06 (Indoor Air Quality) and is on the Board of Directors of the Indoor Air Quality Association and the Florida Public Health Foundation. Because HVAC applications encompass new uses from an U.S. EPA regulatory standpoint, Mr. Baker works closely with the EPA and industry groups, including serving as the chair of the IAQ committee of the Consumer Specialty Products Association, to help formulate policy in this area.

Bob Baker is Chairman and CEO of BBJ Environmental Solutions, Inc., a company specializing in providing clean air through environmentally responsible products, such as BBJ MicroBiocide , BBJ Micro Coil Clean , "FreshDuct Odor Eliminator ", and BBJ Mold and Mildew Remover™ as well as the revolutionary new Power Coil Clean™. For additional information, Mr. Baker can be reached at (800) 889-2251 or through the company web site at http://www.bbjenviro.com.