Abstract: At 10:30 a.m. on November 14, 2017, Employee #1 and Coworker #1, employed by a building services company, were cleaning the exterior windows of a twelve-story office building. They were suspended from a rooftop anchor system and had descended from the fourth to the third floor, 30 feet above the surface. Employee #1's primary lifeline rope, which hung down to the ground, became caught by a bus moving below the employees. Employee #1 was pulled downward, and the rope failed and broke. His secondary lifeline rope did not fail, and it prevented Employee #1 from falling further. The secondary lifeline pulled Employee #1 upward in a sling shot effect, and he struck the side of the building. Emergency services were called, and Employee #1 was transported to the hospital. He was admitted and treated for a laceration over his right eye and a fractured right pinky finger.