How Traffic Lights Work

Traffic lights are a fundamental part of the UK’s road system, controlling the flow of vehicles and pedestrians to ensure safety and efficiency. Understanding the sequence and what each light signifies is crucial for all road users. This guide will break down the UK traffic light system, referencing the Highway Code to provide clear and informative explanations.

The UK Traffic Light Sequence

Red: The red light means you must stop behind the white stop line. Do not proceed until the light changes to green. This is a mandatory requirement under the Highway Code. Highway Code Reference: Rule 109

Red and Amber: The red and amber light means stop. Do not proceed until the green light shows. This indicates that the green light will appear shortly. You should get your car ready to move. Highway Code Reference: Rule 109

Green: The green light means you may go if the way is clear. Take extra care to check for pedestrians and other vehicles that may still be crossing. Highway Code Reference: Rule 109

Amber: The amber light means stop at the stop line. You may proceed if the amber light appears after you have crossed the stop line or are so close to it that to stop might cause an accident. Highway Code Reference: Rule 109

Practical Tips for Drivers

• Anticipate changes: Pay attention to the traffic lights ahead so that you can anticipate when the lights are likely to change.
• Avoid sudden stops: Slow down gradually when approaching traffic lights, especially when the amber light is displayed.
• Check your mirrors: Be aware of vehicles behind you, especially when stopping suddenly.
• Be aware of pedestrians: Always check for pedestrians crossing the road, even when the lights are in your favor.
• Never run a red light: It’s dangerous and illegal. Not only is it unsafe, but it can also result in penalty points and fines.

Understanding the Green Filter Light

A green filter light (also known as a green arrow) allows traffic to proceed in the direction of the arrow, even if other movements are stopped by a red light. This is often used at junctions to allow traffic to turn in a specific direction safely.

When you see a green filter light:

• You may proceed in the direction of the arrow.
• You must still give way to pedestrians and other traffic already in the junction.
• Exercise caution before proceeding, ensuring that it is safe to do so.

Highway Code Reference: Rule 109

The significance of the green filter light is to improve traffic flow and reduce congestion at junctions, while maintaining safety. It allows specific turning movements to occur without conflicting with other traffic streams.

How drivers should respond: As per the Highway Code, drivers must obey the green filter light but must also be vigilant and aware of their surroundings, yielding to pedestrians and other vehicles as necessary.

Summary

Understanding how traffic lights work in the UK, including the standard sequence and the meaning of a green filter light, is essential for safe and responsible driving. Always adhere to the Highway Code and exercise caution on the roads.