Traffic Signals and Intersections
Intersections are where paths cross — and where most urban crashes happen.
Synopsis
Traffic signals manage competing movements at intersections and improve efficiency. Understanding signal phases and intersection behaviour is essential because intersections are consistently the highest-crash locations on urban Indian roads.
Why this matters
Intersections are where the paths of vehicles, pedestrians and cyclists physically cross. A red-light violation is not just a fine — it is a direct collision path with a vehicle that has right of way and is not expecting you.
Expected outcome
You will interpret signal phases correctly, understand intersection priority, and make safer decisions at both signalised and unsignalised junctions.
Learning objectives
After completing this lesson learners should be able to:
- Interpret traffic signal phases
- Understand intersection priority
- Improve decision-making at junctions
- Recognise common intersection risks
Signal Phases
Red means stop before the stop line. Amber means stop unless it is unsafe to do so — it is not a signal to accelerate through. Green means proceed if the intersection is clear. A flashing amber indicates caution — proceed carefully. A flashing red is treated as a stop sign. Dedicated pedestrian phases give people on foot a protected window to cross.
Intersection Risks
The highest-risk conflicts at intersections are: right-turning vehicles crossing oncoming traffic, pedestrians crossing during a permissive turn, cyclists disappearing into the blind spot of turning vehicles, and drivers accelerating through a late amber. Add poor visibility from other vehicles or roadside objects and every conflict becomes harder to see in time.
Safe Practices
Anticipate signal changes — a green that has been on for a while is likely to change. Scan for pedestrians and cyclists before entering the intersection, even on green. Never enter an intersection you cannot clear before the signal turns red. On amber, stop unless doing so would cause a rear-end crash. Never rush through a signal that has just turned red.
Amber is not 'faster'
Accelerating through amber is one of the most common causes of T-bone crashes at intersections. Treat amber as a stop signal by default.
Real-world scenarios
Right turn on a permissive green
You are turning right at a signalised intersection on a plain green (no dedicated arrow). Oncoming traffic is approaching.
→ Who has priority?
Show suggested response
Oncoming traffic has priority. A permissive green means you may turn only when it is safe — you must yield to oncoming vehicles and to pedestrians crossing your path. Wait in the intersection until a safe gap opens.
Key takeaways
- Intersections require active vigilance.
- Signals support orderly movement — they do not eliminate conflict.
- Amber is a stop cue, not an acceleration cue.
Complete this lesson
Take the short quiz to mark this lesson complete and unlock the next.
Lesson 25 of 31 available · 20 min · India-specific