[Code of Federal Regulations] [Title 49, Volume 4] [Revised as of October 1, 2005] From the U.S. Government Printing Office via GPO Access [CITE: 49CFR218.25] [Page 199] TITLE 49--TRANSPORTATION CHAPTER II--FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION PART 218_RAILROAD OPERATING PRACTICES--Table of Contents Subpart B_Blue Signal Protection of Workers Sec. 218.25 Workers on a main track. When workers are on, under, or between rolling equipment on a main track: (a) A blue signal must be displayed at each end of the rolling equipment; and (b) If the rolling equipment to be protected includes one or more locomotives, a blue signal must be attached to the controlling locomotive at a location where it is readily visible to the engineman or operator at the controls of that locomotive. (c) When emergency repair work is to be done on, under, or between a locomotive or one or more cars coupled to a locomotive, and blue signals are not available, the engineman or operator must be notified and effective measures must be taken to protect the workers making the repairs. [44 FR 2175, Jan. 10, 1979, as amended at 48 FR 6123, Feb. 10, 1983]