Abstract: At approximately 4:00 p.m. on August 13, 2019, an employee and coworker were installing membrane roofing material on a section of flat roof over a walkway between a school office and the school's multi-purpose room as part of a renovation project. The employee and coworker did not have a ladder with them to access the roof, so they borrowed a ladder (folding A Frame type, approximately 12ft. tall) from someone at the facility. The employee and coworker needed to get more roofing material from the ground and when they came to the roof edge where the ladder had been set up, they noticed that the ladder they had used to access the roof had been replaced with a shorter ladder (folding A Frame type, approximately 8 ft. tall). Neither of the two workers knew who switched the ladders. The coworker descended the ladder first. When the employee attempted to descend from the roof, he placed his foot on the top cap of the ladder, which shifted inward (towards the roof edge) causing him to lose his balance and he fell approximately 9 ft. onto the concrete sidewalk. The employee suffered a fractured left hip, bruised left wrist, back pain, and bruised left knee. The employee was hospitalized for treatment and received surgery on his hip.