Abstract: Employee #1, a maintenance mechanic, was working on a hydraulic crane. Between 200 and 300 ft away, a coworker was using a blow torch to dismantle a 1,000- to 2,000-gallon aboveground tank. Either smoke or gases must have been emitted into the atmosphere and traveled downwind to where Employee #1 was working, because he became ill and had to go home. His condition worsened and his wife took him to Kaiser Permanente Hospital, where he was treated, observed, and released in less than 24 hours. The vessel involved had been dismantled and removed before the accident investigation, and the cause of the incident could not be determined.