Deciphering the code
Published: May 1, 2006
|Before radio communication came into wide use in the 1960's, a locomotive's whistle was an important tool in conveying information to other employees, both on and off the train, and many signals were on the books. |
The General Code Of Operating Rules, used by many railroads, contains the following list of whistle signals and their meanings:
Note: "o" denotes a short sound; while a "-" is for a longer sound.
- When stopped, air brakes applied, pressure equalized.
- - Release brakes, proceed.
0 0 Acknowledgement of any signal not otherwise provided for.
0 0 0 When stopped, back up; acknowledgement of hand signal to back up.
0 0 0 0 Request for signal to be given or repeated if not understood.
- 0 0 0 Flagman protect rear of train.
0 0 0 - Flagman protect front of train.
- - - - Flagman may return from west or south.
- - - - - Flagman may return from east or north.
- - 0 - Approaching public grade crossing.
0 - Inspect brake system for leaks or sticking brakes.
A series of short blasts is sounded in an emergency.
Today, the only signals you're likely to hear regularly are the grade-crossing warning (which is also often used to warn employees or others on the tracks); two (or three) shorts to indicate the engineer has received a signal to start the train forward (or backward); and one long blast when a train is approaching a station on a track next to a platform.