DESC: The EPA has reported that indoor air can be up to 5 times more polluted than the air outside. And when you consider that we spend 90 percent of our time indoors exposing our bodies to airborne contaminantsit's unbelievable. Doctors have said that the use of a portable air cleaner is a great way to help maintain a fresher and cleaner home environment. Also, clean air helps reduce stress and promotes relaxation.