Lesson 2Mold Remediation in Heating, Ventilation, and Air Conditioning (HVAC) Systems
Mold remediation involving a heating, ventilation, and air conditioning (HVAC) system should be done only by professionals experienced in working with HVAC systems. Professionals may have several different methods and techniques for approaching HVAC remediation. As with the rest of a mold remediation project, professional judgment is required when working with HVAC systems, and professionals may use materials, methods, and techniques not mentioned in this course.
An HVAC system found to be contaminated with mold should be turned off and not used until the system has been remediated; using a mold-contaminated HVAC system may spread mold throughout the building and increase the exposure of building occupants. (There may be some exceptions or instances when all or part or the HVAC system can be run, based on professional judgment, if there is no risk of increasing occupant or worker exposure). If possible, the HVAC system should be remediated during off hours when the building is not in use.
Effective containment of the area served by the ventilation system is important to avoid the spread of mold and mold-contaminated materials. All intakes and supply vents should be sealed with plastic and tape, and negative air pressure should be maintained in work areas. (A fan can be used.) Contaminated porous materials in the HVAC system should be bagged and removed. Materials that can be cleaned should be vacuumed with a HEPA vacuum or cleaned with a moist cloth and detergent solution. All items should be dried promptly.
If you consider duct cleaning, first consult EPA's guide Should You Have the Air Ducts in Your Home Cleaned? (See the Resource List.)