While we understand that whistling may be disturbing at times, federal regulations in the US and Canada mandate whistling at all public crossings. Train whistles are safety devices that alert motorists and pedestrians to the presence of an approaching train and warn trespassers away from the rail right-of-way. Locomotive engineers follow a detailed set of instructions that outline when a whistle must be sounded and the whistling sequence to be used. Train crews will also use the whistle if there is a work project in the area to notify the work gang on or near the track that a train is approaching.
In certain circumstances, a particular crossing may be exempt from whistling requirements.
To learn more about whistle rules click here.