Abstract: At 2:30 p.m. on January 28, 1997, Employee #1, an iron worker with Washington Iron Works, was in the basket of a Snorkelift aerial device truck, welding steel on the roof structure of a building under construction. He was working alone and needed to reposition himself to improve his access to the job. Employee #1 was at the controls and was moving the aerial lift when his back became caught between a steel roof beam and the basket cage. He was leaning forward with his head down, but with his left hand he somehow switched the EMERGENCY button. At this point he was experiencing severe chest pains and he could not talk or move his body. Shortly thereafter, his supervisor walked into the building and saw Employee #1 pinned against the beam. He alerted several coworkers outside the building and they helped extricate Employee #1. He suffered crushing chest injuries and was transported to San Pedro (CA) Peninsula Hospital. The main causal factors in this accident were (1) failure to ensure that Employee #1 was specifically trained for this type of work, in accordance with the lift manufacturer's recommendations; and (2) failure on the part of Employee #1 to survey the vicinity to determine possible obstructions before moving the aerial device.