Abstract: Mitac Information Systems Corp. is an employer engaged in computer hardware manufacturing. Prior to the accident, an employee, a maintenance lead, and a coworker, another maintenance employee, were assigned to run network and sensor cables in the drop ceiling area above the test chamber room. At 2:20 p.m. on December 20, 2021, the employee was in the drop ceiling area and lost balance, striking his chest against a metal rail in the drop ceiling. The employee was transported to a hospital in Fremont, CA. The employee was then transferred to another hospital in Castro Valley, CA that same night due to bleeding in the liver. The employee was admitted for trauma care, including fractures of the right 4th through 9th ribs, a small right-sided pneumothorax, and a liver mass that was diagnosed as a traumatic hematoma. The employee was discharged on December 23, 2021. The main factor that caused the accident was that the employee went against instruction from the supervisor to complete the task using a ladder from the ground floor. This was determined the previous day because of the insufficient work space in the drop ceiling. The Division found no serious accident-related violations. The employer was cited for two general violations. Title 8 CCR 3203(a)(7): The employer did not provide safety training to maintenance employees. Title 8 CCR 3276(f): The employer did not provide ladder training to employees. Struck against metal beam