Abstract: On August 1, 1997, Employee #1 was using a 20 ft extension ladder, Type 1, to clean the 15 ft high second-story, west-side exterior windows on a two-story building. The Werner, model D6120-2, 300 lb extension ladder had a maximum working length of 17 ft. Employee #1 was climbing the ladder when, to the best of his recollection, it didn't stay locked in place and slid down into its lowest position. He either fell or jumped approximately 12 ft onto the concrete walkway, fracturing both heels. Employee #1 was transported to the hospital, where he underwent surgery, followed by an extended period of rehabilitation. He later stated that he could not remember specifics surrounding the incident, and there were no witnesses. Subsequent investigation uncovered no deficiencies in the equipment involved in the accident, all of which was maintained, inspected, and stored properly.