There is little sunlight or moisture in carpets to biodegrade PBTs. So an infant's exposure to PBTs in house dust may be 25 times that of an adult's. Effective cleaning and use of door mats may reduce an infant's dust exposure by 90 to 98 percent. These hygienic measures also reduce the time required for cleaning. Old carpets may contain a reservoir of dust, lead, dust mites, PBTs, carcinogens, fungi and bacteria even if they receive regular cleaning.
Deep dust tends to collect in older or worn carpets.
One of the best ways to measure and reduce dust in a carpet is to use a vacuum with a dust detector on it which shows a green light when there is no more dust coming from the carpet. Hoover, Sears and Panasonic make such vacuums. A family with a baby does not need to own such a vacuum, but they need access to one to monitor and remove deep dust from the carpet. Once the deep dust is removed, they can use it once a year to monitor the effectiveness of their cleaning methods. Dust, smoke, dust mites and mold are the enemy of all people but especially infants.