The Chinese capital city of Beijing has upgraded 800 traffic lights at 100 major crossroads to alert blind and partially sighted people against colour changes.

The traffic lights now indicate the time remaining until the traffic lights change as well as broadcast voice reminders to the visually impaired.

The change in colour of traffic lights is done using radio frequency identification sensors installed near the traffic lights. On detecting a bus, the sensor sends signals to the traffic light, which changes its colour to green to allow enough time for the bus to pass.