While dirty ducts don't necessarily mean that there's unhealthy air in the home, school, or workplace, they can contribute to more serious health problems or harbor contaminants that could cause serious issues for people with respiratory illnesses, autoimmune disorders, or allergies. Knowledge about cleaning air ducts is in its early stages, so there can be no general recommendation on whether you should clean your home's air ducts. The Environmental Protection Agency (EPA) urges you to read this document in its entirety, as it provides important information on the subject. Duct cleaning has never been proven to actually prevent health problems.
Nor do studies conclusively show that this particle (e.g.) contributes to health problems in the home. This is because much of the dirt in the air ducts adheres to duct surfaces and does not necessarily enter the living space. It's important to note that dirty air ducts are just one of many possible sources of particulate matter in homes. Contaminants that enter the home from both outdoor and indoor activities, such as cooking, cleaning, smoking, or simply moving around, can cause greater exposure to contaminants than dirty air ducts.
In addition, there is no evidence that a small amount of household dust or other particles in air ducts poses a health risk. If any of the conditions identified above exist, it usually suggests one or more underlying causes. Before cleaning, modernizing, or replacing ducts, the cause or causes must be corrected, or else the problem is likely to recur. Some research suggests that cleaning the components of the heating and cooling system (e.g., however, there is little evidence that cleaning only the ducts) improves the efficiency of system.
You may consider cleaning air ducts simply because it seems logical that air ducts 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 could be harmful. The EPA does not recommend that air ducts be cleaned routinely, but only when necessary. However, the EPA recommends that if you have an oven, stove, or chimney that burns fuel, they be inspected to make sure they are working properly and serviced before each heating season to protect against carbon monoxide poisoning. If you decide to clean your air ducts, take the same consumer precautions you would normally take when evaluating the competence and reliability of the service provider.
Whether or not you decide to clean your home's air ducts, preventing water and dirt from entering the system is the most effective way to prevent contamination (see How to Prevent Duct Contamination). If you decide to clean your heating and cooling system, it's important to ensure that the service provider is committed to cleaning all components of the system and is qualified to do so. In addition, the service provider can propose the application of chemical biocides, designed to eliminate microbiological contaminants, inside the ducts and in other components of the system. Some service providers may also suggest the application of chemical treatments (sealants or other encapsulants) to encapsulate or cover the interior 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 ducts.
These practices have not yet been thoroughly researched and you should be well informed before deciding to allow the use of biocides or chemical treatments in air ducts. They should only be applied, if at all, after the system has been properly cleaned to remove all visible dust or dirt. Knowledge about the potential benefits and potential problems of cleaning air ducts is limited. Since the conditions in every home are different, it's impossible to generalize about whether cleaning the air ducts in your home would be beneficial or not. On the other hand, if your family members have unusual or unexplained symptoms or illnesses that you think might be related to your home environment, you should discuss the situation with your doctor.
The EPA has published several publications as guidance on identifying potential indoor air quality problems and ways to prevent or solve them. You may consider cleaning the air vents simply because it seems logical that they get dirty over time and should be cleaned from time to time. While debate over regular duct cleaning continues, there is no evidence suggesting such cleaning is harmful as long as it is done properly. On the other hand, if a service provider doesn't follow proper procedures for cleaning air vents then it can cause indoor air problems such as inadequate vacuum collection system releasing more dust and dirt than necessary into your living space; careless or inadequately trained service provider damaging your heating and cooling system; increased heating and cooling costs; expensive repairs; etc. This is because much of dirt accumulating inside air vents adheres to surfaces and does not necessarily enter living space while there is no evidence suggesting a small amount of household dust poses a health risk either way. The EPA does not recommend routine cleaning but only when necessary due to continuing uncertainty about benefits under most circumstances; however they do recommend inspection for ovens/stoves/chimneys burning fuel before each heating season for protection against carbon monoxide poisoning. Some research also suggests that cleaning dirty cooling coils/fans/heat exchangers can improve efficiency of heating/cooling systems but there is little evidence indicating simply cleaning duct system will increase efficiency either way.
If you decide on getting your vents cleaned then make sure you take consumer precautions when evaluating competence/reliability of service provider; ensure they are committed to cleaning all components; apply biocides/chemical treatments only after proper cleaning; etc.
