Aiding in the improved score was UP's Twin Cities Service Unit, which achieved a 70 percent improvement in 2012 compared to 2011, with an employee reportable injury rate of 0.56.

The Twin Cities Service Unit has about 900 employees and is made up of more than 650 miles of track in Minnesota, western Wisconsin and northern Iowa.

Bob Grimaila, Union Pacific vice president safety, security and environment, said, "Our safety leadership development and continuous process improvement team efforts, including those driving down operational variability to provide a more predictable work environment, play key roles in safety results."