Regarding duct cleaning today, the most important angle to your research from is the “health benefits” angle and than mechanical .It is the most important benefit since as humans we need to breathe “clean and healthy” air. According to the," American Lung Association, Indoor Air Pollution is wide spread”. You are more likely to get sick from pollution in your home and office than from pollution in the air outside." Your home's air is 50 to 100 times more polluted than outdoor air. Allergies and sinus conditions are commonly caused by mildew in the ductwork, bacteria, viruses, fungi and dust mites in your home's air.