Smog-Fighting Shingles Helping to Clean California Air

Northern California is famous for many things, the sun, the surf, the wine, but it has also been infamous for its smog. Smog is a noxious collection of nitrogen and sulfur oxides, along with smoke and dirty particles, which all combine to form a foglike haze in the air. But some new technology is promising to turn a roof into an air cleaner. VOA's Kevin Enochs reports.