Dave Klug walked out of a Hanford tank farm control room on a cold, calm night in January 2010 into air that took his breath away. "Immediately, I had tightness in my chest. I lost feeling in my face. My heart rate was going crazy," he said. Klug, a longtime Hanford tank farm worker, was one of several workers who talked about their experiences with chemical vapors at a forum Wednesday night in Pasco. Klug was off work for 11 months after that night and now has 30 percent permanent, partial disability for reactive airway disease and occupational asthma, he said. Those who talked at the forum kept coming back to two types of illnesses they believe are caused by chemical vapors -- breathing problems, as Klug described, and neurological issues, including a brain disease called toxic encephalopathy. Toxic encephalopathy is what Barbara Sall said led to the dementia and death of her husband, a Hanford carpenter who died at the age of 57. The forum -- organized by Hanford Challenge, union Local 598 and state Attorney General Bob Ferguson -- drew about 200 people.