Abstract: On April 20, 2012, Employee #1 a cable installer, was installing low voltage wiring to a local middle school. Employee #1 went to work early and was looking for the restroom. The doors to the building were locked. The employee went back to his car which was parked nearby and waited for his coworkers to arrive. Shortly, he decided to get into the building by using an extension ladder that was already set up. When the employee reached the upper floor which was 12 ft high, he checked to see what he could do and went down the same ladder to gather his tools and start work. Employee #1 descended almost halfway down the ladder when he felt the ladder kicking out and he fell. The employee landed on the ground on his right side. The employee tried to get up to make a call on his cell phone but could not move. There was no one else present. He lay on the ground for approximately 10 minutes. He was not worried because he knew other employees would be coming to work soon. Another employee came to work seeing Employee #1 was on the ground and called the emergency services. The other employee had also contacted the employer and took some pictures at the incident scene. Employee #1 was taken to San Francisco General Hospital, where he was treated for broken left rib. The rib had impacted part of his spine and nerves. The employee stayed in the hospital for eleven days.