US Railroad General Code of Operating Rules (GCOR) Practice Test

What does a CLEAR aspect indicate in signaling?

Solid yellow over solid yellow

Solid green or solid green over solid red

A CLEAR aspect in signaling is indicated by a solid green signal or a solid green signal over a solid red signal. This aspect communicates to train operators that the track ahead is clear for travel, meaning that they can proceed with confidence that there are no obstructions or signals restricting their movement.

When encountering a CLEAR aspect, engineers and train crews understand that they can maintain or increase their speed, as there are no safety concerns at the moment. The solid green signals signify safe operation that aligns with the expectations of the railroad's operating rules.

Other signaling aspects, such as solid yellow or red signals, would indicate caution or stop conditions, therefore not aligning with the positive indication presented by the CLEAR aspect.

Flashing red

Solid red over solid green