One of the most common types of legal cases for which human factors expertise is sought is termed "slip, trip, and fall." These cases usually involve injuries that are the result of slipping on ice or liquids, tripping over an obstacle, or falling down stairs or some other elevated platform.
Because instances of slipping, tripping, and falling are so commonplace, there has been quite a bit of research to determine the causative factors associated with such incidents. 
A number of human factors issues can be involved in slip, trip, and fall cases. These include age-related balance and coordination decrements, visual perception, expectations, the biomechanics of ascending and descending stairs, the design of ramps and stairs, etc.
Some of the most interesting slip, trip, and fall cases involve the ability of people to see slipping and tripping hazards, such as liquids or ice. In almost all such cases, it is possible to measure various parameters that can be used to calculate visual contrast, reflections, and other factors that contribute to the ability to see (or to not see) slipping and tripping hazards.
