I thought pollution was outside. Why should I be worried about my air indoors?

We spend 90% of our time every day indoors. Plus, today’s efficient, airtight homes are excellent at conserving energy, but that also makes them better at trapping potentially irritating particles inside the home. With the rising number of people who suffer from allergies and asthma, indoor air quality has become more and more important to our general health and well-being.