When it comes to dust and allergens, carpets tend to hold them in a pile until they are vacuumed. When you sweep hard surface floors, or when a draft comes into your room, allergens can enter the air and your lungs. In this instance, the carpet is better for someone with allergies. On the other hand, a carpet that is subject to prolonged moisture and dirt can be a breeding ground for mold and mildew; in which case the carpet may increase your allergic symptoms. You can, however, choose synthetic carpets, which are mold and mildew resistant and hinder the growth of these allergens. Frequent professional steam cleaning will also help to keep your carpets clean and safe.
When having an old carpet removed, it is recommended that you leave the premises prior to the removal as this can stir up a lot of dust and allergens. Also, have workers remove the used carpet to a safe place out of your home, and vacuum all areas where carpeting was removed.