If you're living in Miami-Dade County, FL and wondering if your air ducts need cleaning, there are some common signs to look out for. If you notice that your duct vents are clogged with dust and dirt, the presence of mold (26%) inside or outside your air conditioning system, or unstable or poor air flow in the house, it's likely that your air ducts need to be cleaned. The Environmental Protection Agency (EPA) recommends that air ducts should be cleaned at least once a year. However, if you live in a warmer climate such as Florida, it is recommended that they be cleaned more often - once in early spring and once in early fall.
The Florida Department of Health has developed information to address some of the most common questions and concerns about indoor mold, how it affects human health, and ways you can prevent or eliminate it. Although knowledge about cleaning air ducts is still in its early stages, the EPA does not recommend that air ducts be cleaned routinely, but only when necessary. Before cleaning, reconditioning, or replacing the ducts, the cause or causes must be corrected, or else the problem is likely to reappear. Some research suggests that cleaning the components of the heating and cooling system (e.g., heating coils, cooling coils, fans and heat exchangers) may improve system efficiency and reduce pollutant levels.
However, there is little evidence that cleaning only the ducts improves system efficiency. You may want to consider cleaning your air ducts simply because it seems logical that the air ducts will get dirty over time and should be cleaned from time to time. As long as cleaning is done properly, there is no evidence to suggest that such cleaning is harmful. It's important to note that dirty air ducts are just one of many possible sources of particulate matter that are present in homes.
Pollutants that enter the home from both outdoor and indoor activities, such as cooking, cleaning, smoking, or just moving around can cause greater exposure to pollutants than dirty air ducts. In addition, there is no evidence that a small amount of household dust or other particles in air ducts poses any health risk. If you decide to have your air ducts cleaned, take the same consumer precautions you would normally take when evaluating the competence and reliability of the service provider. Whether you decide to clean your home's air ducts or not, preventing water and dirt from entering the system is the most effective way to avoid contamination (see How to Prevent Duct Contamination).
If you decide to clean your heating and cooling system, it's important to make sure that the service provider agrees to clean all components of the system and is qualified to do so. In addition, they may propose the application of chemical biocides designed to remove microbiological contaminants inside ducts and in other components of the system. Some service providers may also suggest applying chemical treatments (sealants or other encapsulants) to encapsulate or cover the inner surfaces of air ducts and equipment housings because they believe they will control mold growth or prevent the release of dirt particles or fibers from the ducts. These practices have not yet been thoroughly investigated and you should be fully informed before deciding to allow them in your air ducts.
They should only be applied if at all after the system has been properly cleaned of all visible dust or debris. Knowledge about the potential benefits and potential problems of air duct cleaning is limited. Since conditions in every home are different, it's impossible to generalize about whether cleaning your home's air ducts would be beneficial or not. On the other hand, if family members have unusual or unexplained symptoms or illnesses that you think might be related to your home environment, you should discuss this with your doctor.
The EPA has published several publications for guidance on how to identify potential indoor air quality problems and ways to prevent or fix them.
