"This review provides the reader with information for use in advanced-level radioactive material transportation training. Since the beginning of the atomic energy industry over 50 years ago, there has been an excellent record of safety in the transportation of nuclear materials. It is estimated that over four million packages containing radioactive material are transported in commerce annually within the U.S. To date, there have been no known deaths or serious injuries to transport workers, emergency services personnel, or the general public as a result of the radioactive nature of the material. This safety record can be attributed to the proper packaging of radioactive material and the effectiveness of the transportation safety standards and regulations."
U.S. Office of Hazardous Material Safety: http://hazmat.dot.gov