Abstract: At approximately 10:00 a.m. on April 1, 2014, Employee #1, employed by a concrete construction company, was working on the fourth floor of a commercial building under construction. Employee #1 stepped onto unsupported plywood sheeting panels that were constructed as part of the deck shoring system. He fell through the sheeting to the third floor, a fall height of more than 7.5 feet to the concrete floor below. Emergency services were called, and Employee #1 was transported to the hospital, where he was admitted and treated for a fractured right forearm, a dislocated disc, and broken teeth. He required hospitalization for more than 24 hours. This event was investigated by Cal/OSHA. During the investigation, it was determined that the employer had been subcontracted to build the structural and non-structural concrete for the four-story commercial building. At the time of Employee #1's fall, another work crew was stripping the forms on the third floor in the area below Employee #1's position on the fourth floor. The report listed the following contributing causal factor: Guardrails were not installed prior to stripping the forms.