Ten percent of playground accidents are due to fighting among visitors, a recent NIH study showed. A much larger percentage of playground accidents, however, result from unforeseen equipment failure involving swings, slides, climbing frames, metal bars, merry-go-rounds. Slides and rope-plank swings are frequently involved in injuries and backward falls. Sometimes the results are dire. Playground accidents frequently lead to fractures of the extremities or concussion of the brain. To help prevent these accidents and determine the causes of failure, the BEAR engineering team employs various methodologies to analyze playgrounds.