Have you ever driven at night and noticed that cat eyes or highway bumps sometimes have different colors?
Well, the reflective units that protect us when driving at night are colored differently to communicate different things.
The colors of the reflective nubs serve a real purpose – and can really help you with poor visibility on unlit routes or in dense fog.
It has been around since the 1930s and the details of how it works are set out in Rule 132 of the Highway Code.
There are five colors: red, green, blue, white and amber.
The most commonly seen lights are the standard white lights, as these mark lanes or the middle of a road. On a regular three lane highway you will see two rows of them.
Amber cat eyes appear across the street to mark the median – and to stop you from thoughtlessly changing lanes to the right.
Red traffic lights, on the other hand, indicate the left edge of the road – before you hit the crash barriers or drift onto the hard shoulder.
Green indicates that an intersection is either entering or exiting a freeway, while blue is used for emergency services.
You will find white rivets between the lanes of expressways or motorways.
In addition to the different colors, the raised studs also help to remind the driver acoustically and sensorily not to leave the lane. Alongside them, rumble strips are used to do the same.
Neil Greig, Policy and Research Director at IAM RoadSmart, said: “Reflective road lugs can be a lifesaver in fog and reduced visibility as they can provide you with important additional information you may need to stay in inclement weather. Unfortunately, the most common studs we see are the yellow ones scattered along the many construction sites on our freeways and federal highways.
“You’re always changing, so it’s important to stay alert and make sure you’re following the right track.”