According to the Asthma and Allergy Foundation of America (AAFA), allergies and asthma afflict about 57 million Americans. Both have been associated with the increasing amount of time we spend indoors, both at work and at home; the tightness of modern buildings; and with insufficient ventilation.
Asthma sufferers in particular can be affected by pollutants such as secondhand smoke, dust mite feces, animal dander, mold spores, and even cooking emissions.