Abstract: Employee #1 and two other employees set a mobile scaffold 27-inches wide by 7-feet long by 69-inches high on a 32-inch wide runway area between the elevator shaft and the stairwell in order to install core boards. One of the employees removed the guardrail that was located in front of a 10- foot stretch of the elevator shaft before the scaffold was put in place so that the core boards could be placed around the elevator shaft opening. After the scaffold was placed and the wheels were locked, Employee #1 went under the scaffold to pass 12-foot long core boards up to the employee on the scaffold. The scaffold shifted toward the 29-foot deep elevator shaft. The employee on top of the scaffold held on to the ceiling I-beam as the scaffold went over into the shaft. Employee #1 was caught by the scaffold and pulled into the shaft, falling 29 feet. Employee #1 suffered from a broken back, concussion, and internal injuries. The scaffold was not fully planked, there were no guardrails and the employees were not tied off.