This simple animation depicts an incident whereby an individual exits a parking garage at the same time the overhead door magnet assembly becomes detached from the door frame and falls, striking the individual on the head. Our engineers reconstructed the incident to determine the peak impact forces and accelerations of the magnet striking the individual’s head. Using the reconstructed mechanics of the incident, our biomechanical expert then calculated key biomechanical parameters including Head Injury Criterion (HIC) and Neck Injury Criterion (NIJ) to determine the probability of injury to the individual’s head and neck. Inspections of the incident site and subject magnetic lock, in addition to a review of service records and manufacturer installation instructions, revealed the fasteners for the door magnet assembly did not meet the manufacturer’s recommended specifications. The fasteners had a history of loosening or falling from the magnet assembly, explaining the probable cause for the magnet’s detachment from the door frame.