Whistle Signals and What They Say

When engineers sound the horn of a train, it carries a message. Below are the examples of sounds used by engineers and what those sounds say to others.

short sound of horn (toot) long sound of horn

What it means
Applying brakes. Stopping.
Engineers answer to any signal not otherwise provided for.
When standing, about to back up.
When running, stopping at next station.
Alarm for persons or animals on the track.
Approaching stations, junctions, and railroad crossings.
A second section is following.
Flagman protect rear of train.
Releasing brakes. Proceeding.
Approaching meeting-points or waiting-points of trains
Flagman may return from west or south.
Flagman may return from east or north.

http://www.railfanclub.org/fieldguide3whistle.asp viewed December 29, 2002