
Introduction
People spend 87% of their time indoors, yet we often think of our exposure to pol-
lutants of outdoor origin first—such as air pollution—and neglect to consider what
is happening while we are inside our homes, schools, or offices, seemingly protected
from outdoor elements. Research focusing on the indoor environments demonstrates
that building occupants are exposed to a mixture of pollutants of chemical and bio-
logical origin. The sources of these pollutants are varied; they may be emitted from
building materials or consumer products, introduced via outdoor air infiltration, or
shed from building occupants. For pollutants with indoor ...