Duct cleaning has never been shown to actually prevent health problems.
EPA (US Environmental Protection Agency) website.
Since 99.9% of all Southwest Florida residential homes have a certain amount of fiberglass duct board incorporated into the air distribution system, making it impossible to clean. Fiberglass duct board is porous, allowing any contaminants to absorb into the duct board. Duct cleaning equipment was designed for hard surface duct systems, such as sheet metal.
Once fiberglass duct board or liner is contaminated with mold, cleaning is not sufficient to prevent regrowth and there are no EPA-registered biocides for the treatment of porous duct materials. (located under bullet point “Unresolved Issues of Duct Cleaning”)
Click here for EPA guidelines – (located under bullet point “Unresolved Issues of Duct Cleaning”)
Since 99.9% of all residential duct systems have a certain amount of porous fiberglass duct work, you should never try and sanitize it. The sanitization product will be absorbed into the porous fiberglass. Chemical biocides are regulated by EPA under the Federal pesticide law. It is a violation of Federal Law to use a pesticide product in any manner inconsistent with the label directions. There is NO product currently registered as biocides for use on fiberglass duct board or fiber glass lined ducts.
Be careful of companies offering duct sanitization.
Click here for EPA biocide guidelines – (located under bullet point “Unresolved Issues of Duct Cleaning”)