Abstract: At approximately 7:30 a.m. on December 4, 2004, Employee #1 was performing his duties as a planner. The employer is an aerospace company that manufactures planes, rockets, and space vehicles. Employee #1 was leaving building Number 636 and was walking down the southwest staircase. Employee #1 stated that, as he reached the bottom of the stairs, he stumbled and fell to the ground. Employee #1 attributed his fall to a loss of balance and stated that there were no problems or safety hazards on the stairs at the time of his accident. During inspection, these stairs were observed in good condition with stair rails and mid-rails as required. Immediately following the accident, Employee #1 went to his physician and was diagnosed with bruised ribs and a chest contusion, however, after a few days, he started experiencing a shortness of breath and returned to the doctor. Employee #1 was diagnosed and then hospitalized from December 13 to December 15, 2004, for a rib fracture.