John Cletheroe's
USA and Canada Holiday Hints


Road Signs In The USA And Canada - Left Turn Yield On Green

The information on this page, although extensively checked and believed to be correct, is completely unofficial and is provided for general guidance purposes only.

This road sign is seen at some intersections controlled by traffic lights and is always in the form of a plate, positioned so as to be obvious to the drivers of vehicles turning left.

The "Left Turn Yield On Green" traffic sign has a green circle at the bottom, which in poor lighting conditions could be mistaken for a green traffic light. In US highway engineering terminology this green circle is usually called a green ball but on the sign it is always depicted as a simple flat green circle, not a three dimensional ball.

The official meaning of this sign is to inform the drivers of vehicles turning left that when their left turn signal is a green circle then traffic in the opposite direction is not stopped, and they must yield to it.

In most cases, the traffic lights at intersections where this sign is present will operate in both protected mode and permissive mode. These are terms used in US traffic engineering terminology:

Most commonly, the traffic lights at these intersections will go through a protected left turn phase followed by a permissive left turn phase on each cycle. However, in some cases the lights may change between protected only, permissive only, or protected/permissive (both modes in each cycle) depending on the time of day.

It would seem that officially this sign is regarded as somewhat redundant. The use of a green arrow or a green circle should be sufficient indication of whether oncoming traffic is stopped or not. However, the sign is often installed as a safety measure following a number of accidents at an intersection. The sign can therefore perhaps be additionally read as: "Take extra care, this is a dangerous intersection".

The sign is also installed when the way that the traffic lights operate at an intersection is changed so as to include a permissive mode phase where previously there was none.

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Driving

Driving - Road Signs, Signposts And Highway Marker Shields

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Most recently modified 21-Jul-02