As an hvac contractor, what do you need to know about mold, and what is the role of the sheet metal fabricator/installer?
Henry Berman, TRI MED Environmental Research Co., Carmel, Ind., said that in many sick buildings the central hvac system has become the "heart" of the problem. "The response to these new indoor challenges was to modify building codes that require the entrance of more outside air to create a greater air exchange," Berman said. "This however adds additional pollutants including various species of mold and fungi.
"Duct systems act like a body's blood vessels," he said, "routinely distributing conditioned air throughout a building, becoming the very pathways which microbes can be carried from these reservoirs to distribute through the building." Also, drain pans that are built into a system to trap condensate, blower housings, baffles and louvers all can serve as reservoirs of microbial colonization.
Berman was one of a panel who spoke on mold at the 34th annual Air Conditioning Contractors of America (ACCA) conference here February 27-March 1.
The interest in mold is making it one of the most prominent and potent of indoor air quality problems. According to Berman, after news of floods or other such disasters, many attorneys are known to call potential clients with offers of free mold testing. And many people who never suffered from allergies before are suddenly becoming allergic due to mold exposure. "Allergies are like a bucket that overflows with one more drop," he said, adding, "Filtration is not enough."
Berman's company advocates the use of carefully controlled amounts of ozone and the use of a germicidal ultraviolet light to kill airborne mold spores. In an experiment, the ozone generated did not exceed OSHA levels for an occupied space, he said. The resulting "low cost air purification system" his company developed, he said, was found to be safe and effective in reducing mold spores.
It is tempting, said Robert Baker, BBJ Environmental Solutions Inc., Tampa, Fla., but potentially hazardous, to spray the inside of a duct system with an antimicrobial to kill existing mold spores or airborne pathogens. But most, if not all, of these cleaning agents are not meant to be aerosolized, or breathed in. Some, such as gluteraldehydes, used for sterilizing medical instruments, are carcinogens and should be used only under controlled conditions.
Limiting liabilityMeanwhile, PHCC member Sam Dowdy of S & D Plumbing in Taylor, Texas, has developed a mold liability agreement that he has agreed to share with PHCC members. One passage of note reads: "Customer assumes the risk of all damages or injury to property or persons from mold or mold related Claims resulting from the Plumbing Services? Owner hereby acknowledges that Company has not made any representations to Owner regarding the extent or potential of mold which may or could result from the Plumbing Services nor the consequences of mold which may or could arise, and the conditions which may result in mold and this Agreement is to assure the Company that it can undertake the Plumbing Services without liability for any known or unknown conditions which may result in mold."
The disclaimer stems, in part, from a decision by the Texas Insurance Commissioner to stress consumer choice on mold-related insurance coverage. The new order reportedly retains coverage for removing mold related to water damage, but it eliminates coverage for higher priced procedures, such as testing, treating, containing or disposing of mold which that which is necessary to repair or replace property damaged by water. "Such procedures have contributed to unexpected and dramatic premium increases," he said, according to an article in the Invironment Professional newsletter for January ("Texas Strives for Balance in Mold Insurance").
To see the complete document, visit www.PHCC.org. Dowdy is a member of the PHCC Texas Task Force on Mold Issues.
In other "moldy" news: