Good indoor air quality is important. In fact, according to the Environmental Protection Agency, the concentration of some pollutants is often two to five times higher indoors than outdoors. Irritants such as bacteria, mold, mildew, viruses, animal dander, radon, pesticides, smoke, wood-burning, cooking and more are common in homes. Considering that the average American spends some 90 percent of their daily lives indoors, that could mean breathing a lot of polluted air. What can you do? Get an air purifier. The right one can significantly decrease the number of pollutants in your home—and help you breathe better.