Is indoor air pollution really a problem?
A popular television commercial from the 1970s shows a Native American man in buckskin and feathers paddling his canoe through ink-black waters, past refineries billowing smoke. He comes aground on a litter-strewn shoreline and finds a freeway clogged with cars and exhaust fumes. Someone chucks fast-food garbage out a car window and it splatters onto his moccasins. The camera zooms in on a single tear streaming down his cheek, while the voiceover tells us “People start pollution. People can stop it.” People have done significant things in the ensuing years to stop some types of air pollution, says William Bahnfleth, director of Penn State’s Indoor Environment Center and professor of architectural engineering. For instance, in 1990, Congress expanded the Environmental Protection Agency’s (EPA) Clean Air Act, giving the agency the power to enforce regulations reducing air pollutant emissions. However, says Bahnfleth, these air quality laws only apply to outdoor air. How safe is the air w
