Abstract: Railcars containing chlorine were connected by manifolds to a bleach manufacturing process as well as to a chlorine repackaging process where 1-ton cylinders and 150-pound cylinders were filled for sale to customers. The manifolds were equipped with air and electric operated valves. The compressed air was introducing debris into the system which caused the actuators to stick and prevent the valves from closing. Employees #1, #2, #3, #4, and #5 were hospitalized as a result of a chlorine release. The investigation revealed that the employer did not fully implement the Process Safety Management requirements by conducting a detailed and complete process hazard analysis.