Abstract: Employee #1 was showing a trainee how to make a salt solution with potassium bromide and potassium iodide. He was standing at the top of four steps, emptying a 25 lb drum of a potassium salt into a tank. He was talking with the trainee and another coworker when he said that he felt dizzy. He then fell straight back while still holding the almost empty drum, striking his head on the concrete floor at the bottom of the steps. Witnesses later stated that he did not attempt to break his fall. One coworker went to get help and the trainee stayed with Employee #1. When the trainee saw his color changing, he administered CPR, whereupon Employee #1 began bleeding from his nose and mouth. The medical examiner indicated that Employee #1 had suffered a heart attack and fractured his skull, either of which could have resulted in his death. According to Employee #1's supervisor, he had not been doing anything different that day, and actually was doing less work than usual since the trainee was doing much of it. Employee #1 had some history of dizzy spells, during which he had to lean up against something for a few minutes, but had never, to the supervisor's knowledge, lost consciousness. The cause of these spells was not known; they did not occur frequently and they had not appeared to be related to any specific activity or event. Employee #1 was not working with chemicals that would be expected to cause dizziness. He was reported to be in relatively good health, although he smoked a pack of cigarettes per day. Employee #1 was not wearing a respirator at the time he fell.