When you think of pollution, tailpipes and smokestacks are probably what come to mind — not your living room. But our homes are filled with noxious substances that can be harmful to your health. Given the fact that we spend from 65 to 90 percent of our time inside, according to the Washington Department of Health, it’s important to keep indoor air clean. When interacting with our customers — whether they’re looking for conservation tips or talking about seasonal energy bills — we consider asking them if they regularly inspect their furnace filters, or if they use a different type of air cleaner.