Grab bars were required on U.S. railroad cars by the Railroad Safety Appliance Act of 1893. Occupational Safety and Health Administration (OSHA) guidelines describe the requirements for grab bar clearance, diameter and spacing on fixed ladders. These regulations state that the clearance in the back of grab bars must be at least 4 inches, the diameter similar to the ladder rungs and, when horizontal, grab bars must be spaced by a continuation of the rung spacing. In 2008-2009 alone, the USDOL Bureau of Labor Statistics reported 241 casualties from ladder falls.