[Code of Federal Regulations] [Title 49, Volume 4] [Revised as of October 1, 2004] From the U.S. Government Printing Office via GPO Access [CITE: 49CFR222.21] [Page 266-267] TITLE 49--TRANSPORTATION CHAPTER II--FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION PART 222_USE OF LOCOMOTIVE HORNS AT PUBLIC HIGHWAY-RAIL GRADE CROSSINGS --Table of Contents Subpart B_Use of Locomotive Horns Sec. 222.21 When must a locomotive horn be used? (a) Except as provided in this part, the locomotive horn on the lead locomotive of a train, lite locomotive consist, individual locomotive, or lead cab car shall be sounded when such locomotive or lead car is approaching and passes through each public highway-rail grade crossing. Sounding of the locomotive horn with two long, one short, and one long blast shall be initiated at a location so as to be in accord with paragraph (b) of this section and shall be repeated or prolonged until the locomotive or train occupies the crossing. This pattern may be varied as necessary where crossings are spaced closely together. (b) The locomotive horn shall begin to be sounded at least 15 seconds, but no more than 20 seconds, before the locomotive enters the crossing, but in no event shall a locomotive horn sounded in accordance with paragraph (a) of this section be sounded more than one-quarter mile (1,320 feet) in advance of [[Page 267]] the nearest public highway-rail grade crossing.