Firefighters face many risks during their jobs, but ironically, the most dangerous part of running into a burning building isn't the flames, it's the smoke. It billows off furniture, appliances and carpets in toxic waves of cancer-causing fumes. That's how about 60 percent of career firefighters will die, according to the International Association of Firefighters. Cancer has become the number one cause of death for firefighters around the country. Hear how the men and women who save lives are now working to save their own.