The One Train Only system

(Extract from IR General Rules : Chapter 13)

      13.01 Use of the One Train Only System.

            Trains may be worked on the One Train Only System, only on
            short terminal branches on the single line.

      13.02 Essentials of the One Train Only System.  Where trains are
      worked on the One Train Only System, only one train shall be on the
      section on which this system is in force, at one and the same time.

      13.03 Authority to enter the section
      
            A Driver shall not take his train into the section unless he is
            in possession of the authority to proceed as prescribed by
            special instructions.

      13.04 Procedure in case of accident or disablement on the One Train
      Only System

            (1) (a) If the train becomes disabled and requires assistance
            or if an accident occurs which renders it impossible for the
            train to proceed, the train shall be protected in accordance
            with the provisions of Rule 6.03 in the direction from which
            assistance, if necessary, is being obtained.

                (b) The Guard of the train shall convey advice of the
            circumstances under which the train has become disabled and is
            not able to proceed, to the Station Master of the station from
            which assistance can best be obtained, and if it is necessary
            for such Guard to proceed to such station, he shall instruct
            the Driver in writing to keep the train stationary until his
            return, and obtain his written acknowledgement.

            (2) (a) Such Station Master, if he is not the Station Master of
            the base station, shall communicate this information to the
            Station Master of the base station. On receipt of such
            information, the Station Master of the base station may allow
            another engine to enter the line.

                (b) The engine so sent shall either be accompanied by the
                Guard of the disabled train, who shall explain to the
                Driver where and under what circumstances the disabled
                train is situated, or the Driver of the Engine so sent
                shall be given a written authority, containing such
                instructions as to where and under what circumstances the
                disabled train is situated and such other particulars as
                may be necessary to enter the line unaccompanied by the
                Guard of the disabled train.

            (3) The Guard of the disabled train shall be responsible for
            the safe and proper working of the line until the disabled
            train has been moved and any other engine sent to the
            assistance of the disabled train has been returned to the base
            station.

            (4) If there is no Guard of a disabled train, the Fireman or
            the Assistant Driver or, if necessary, the Driver shall perform
            the duties imposed by this rule on the Guard, provided that the
            engine is not left unmanned in terms of Rule 4.20.