Human Factors Case Study
Case Synopsis: Plaintiff worked as an operations technician on the 4:00am–12:30pm shift. At approximately 9:00am, plaintiff took his break. As he walked off a short platform, he descended a two step stair system, past a stack of corrugated cardboard, (which was stacked upon roller conveyors to his left), and was struck by a five-ton electric forklift driven by his co-worker.
Expert Analysis: Human factors and safety analysis included a review of all relevant depositions, discovery documents, reports, training records, photographs, etc. Additionally, a site visit was performed. Review of research materials, codes, and standards related to perception in applied settings was conducted to determine if the layout of the work area limited the ability of the plaintiff to see and safely respond to the presence of the forklift crossing his walking path.
Plaintiff’s ability for visual and auditory recognition of the subject forklift prior to and after descending a small flight of steps and beginning to walk to the left, was influenced by a number of factors related to both visual and auditory ques in the environment: (1) The position and height of the corrugated cardboard located between the plaintiff and the subject forklift moving toward him from the left, as he was just stepping past the stored corrugated cardboard, prevented the plaintiff’s visual perception and recognition of the subject forklift. This condition also prevented the forklift driver from seeing the plaintiff. (2) The lack of auditory stimuli located within the accident location area due to the noise created by the operation of the plant machinery that was louder than and in combination with the subject forklift motor (which required the plaintiff and other people within that area to wear hearing protection). (3) Although there was no testimony that the plaintiff saw the convex ceiling mirror, the mirror, which was located 15 to 18 feet away from the subject stair system, would not have provided useful information to the plaintiff because of its distorting effects regarding size and distance perception.
Conclusion: These factors prevented the plaintiff from perceiving and recognizing the subject forklift and prevented the forklift operator from perceiving and recognizing the plaintiff. Case settled.