January 2026

Rule 17. Except as provided in Rule 17 (B), the headlight must be displayed, burning bright, at the front of every train by day and by night. It must be extinguished when a train has stopped clear of the main track to meet a train, or is standing to meet a train at the end of double track or at a junction.

Rule 17 (B) Headlights must be dimmed under conditions below, except in foggy or stormy weather, or when closely approaching or passing over public crossings, or when other conditions make it inadvisable:

In yards where yard engines are employed and at stations where switching Is being done;

When standing close behind another train;

While standing on main track awaiting arrival of an approaching train that is to take siding, but not until approaching train dims its headlight;

Approaching and passing head end and rear end of train on an adjacent track;

Approaching locations where train orders or messages are to be handed up;

At other times to permit passing of signals or when the safety of employees or others requires it.

Source: Union Pacific Railroad Company, Eastern and South-Central Districts and Idaho Division, Operating Rules. Effective date May 1, 1972.