Abstract: At 8:45 a.m. on June 12, 2018, an employee and coworker were preparing to make a descent using a controlled decent apparatus (CDA) using the following equipment: An Alaco metal sectional ladder which was approximately 21 feet tall and pointed at the top (commonly referred to as a window cleaner's ladder); a Sky Genie CDA and seatboard with a working rope line; Sky Genie fall protection equipment consisting of a body harness with D-ring, shock absorber, a safety rope line; and carabiners. The employee had cleaned one row of windows and was setting up to clean the second row of windows that were located above a courtyard. The roof parapet was tall, so the employee set up a metal sectional ladder on the back side of the roof parapet. The employee climbed the ladder to lower the working line and safety line ropes over the parapet. The employee climbed over the edge of the roof parapet to descend down the wall using the CDA. When the employee went over the top of the wall, the employee fell approximately 97 feet to the concrete courtyard. The employee sustained multiple blunt force trauma injuries and other internal injuries and was killed.