Abstract: Employee #1 was part of a crew of construction workers relocating a 60 ft long mobile construction trailer on a grassy area adjacent to a blacktop roadway at a construction site. Concrete blocks had been placed under the trailer's metal frame and tongue to temporarily hold it in position while it was jacked up and moved. Employee #1 and a coworker were under the front area of the trailer, with Employee #1 toward the left side and the coworker toward the right; each was using a 30 ton jack placed under the 3 in. metal beam that ran lengthwise under the trailer. The intent was to place four concrete blocks stacked with 2 by 8 wooden boards under the frame so the trailer would be level prior to anchoring it with metal straps secured to the ground. For some reason, the trailer shifted and fell approximately 18 in. off the jacks. It fell toward the left front side and crushed Employee #1, who died shortly thereafter.