This page is a work in progress. Additional resources will be added soon.
| Whistle/Horn Pattern | Meaning |
|---|---|
| o | Apply brakes. Stop. |
| o o | Engineers answer to any signal not otherwise provided for. |
| o o o | When standing, back. |
| o o o | When running, stop at next station. |
| o o o o | Call for signals. |
| Succession of short sounds | Alarm for persons or livestock on the track. |
| — (extended) | Approaching stations, junctions, and railroad crossing at a grade. |
| — o o | A second station is following. |
| — o o o | Flagman protect rear of the train. |
| — — | Release brakes. Proceed. |
| — — o — | Approaching public crossings at a grade. |
| — — — — | Flagman may return from west or south.* |
| — — — — — | Flagman may return from east or north.* |
| “o” is short “—” is long | *These whistle signals are followed by (o), two (o o), or three (o o o) short sounds when several track are in use. |