The form S-H train order pertains to an extra work train on single
track. It authorizes the train to occupy the main track and do right-of-way
work in the area designated and between the hours specified. The working
limits or time limits of a work extra cannot be extended by superseding the
original order to the work train. If an extension of either or both time
and work limits of the work extra is necessary, the original order must be
annulled and a new order issued.
Copies of this order inform all other
crews traveling in the area of the presence of the work extra and the
flagging instructions it holds, if any. An example follows: "Eng 5440 Works
Extra 0930 Hours Until 1701 Hours Between MD and RK."
In this order, no flagging instructions are specified. Basically, all
work extras are required to protect, that is, flag, against all other extras
and, of course, against all other trains of superior class.
order specifies nothing to the contrary, everybody reading it knows that the
work extra is to protect itself against all movements in both directions.
This order, however, may be amended to read: "Eng 5440 Works Extra 0930
Hours Until 1701 Hours Between MD and RK Not Protecting Against Westward
Or, "...Not Protecting Against Extra Trains."
designated area can be stated as between kilometer posts instead of between
stations. Paragraph 5.19 explains this more fully.
Work extras must, unless otherwise instructed, protect against extra
trains in both directions. Therefore, it is improper to tell a work extra
to protect against an extra until after it has been told not to protect.
Occasionally, it might be necessary to make a work extra superior to all
trains. This might occur when a wreck train is called to an accident scene.
If so, the following order might be typical: "Work Extra 9510 Has Right Over
All Trains Between DN Tower And BL From 1330 Until 1830 Hours."
The form D-H train order is used for work extras on double track or on
two or more tracks, as well as specifying the track or tracks the work train
is to occupy. The rules provide that the working limits should be as short
as possible. In the few books published on dispatching, examples show the
working limits as the areas between two or more adjoining stations, as the
examples in subparagraphs a through c specify. In actual rail operations,
however, the working limits may frequently be only 2 or 3 kilometers long.
Where the working area is comparatively short, kilometer posts instead of