A rumble device, such as rumble strips, provide a visual, audible and vibratory effect used to alert drivers and riders to a hazard ahead and to make them aware of their speed.
What should you do when you see, hear, or feel a rumble device?
The first thought you should have when you notice a rumble device, is that you need to slow down safely. There is little evidence to support rumble devices actually slowing down your speed for you. As such, you should not rely on them to adjust your speed for you. Be sure to check your mirrors and make sure you are holding the steering wheel correctly. Do this as you slow down on your approach to the hazard, as indicated by the rumble strip(s).
Rumble Strips
Rumble strips are designed to be seen, heard, and felt in order to warn drivers of an impending hazard. They are usually used in rural settings and to warn drivers that they are approaching hazards like sharp bends and/or junctions. However, they can also be found on the line that separates the hard shoulder and the left-hand lane on the motorway. When used with gateways, they may indicate the beginning of a set of traffic calming measures.
Rumble strips are usually used in groups. Each group usually consists of between 2 and 5 rumble strips but the spacing between groups will vary according to the road and hazard. They are sometimes also known as jiggle bars and rumble areas but the fundamental purpose of any rumble device is always fourfold:
- To be seen
- To be heard > Alert driver to impending hazard
- To be felt
Theory Test Question
Did you try and answer the theory test question: What’s a rumble device designed to do? Let’s have a look at each answer in turn:
Prevent cattle escaping
Wrong! Rumble strips would be ineffective stopping cattle escaping as they are usually painted on to roads. They are designed to alert drivers by causing the car to vibrate, be heard by the driver, and be seen by the driver.
Alert you to low tyre pressure
Wrong! You should regularly check your tyre pressure yourself and always check it before a long journey or when the car is heavily loaded.
Alert you to a hazard
Correct! Rumble devices cause an audible, visual, and tactile warning system that should quickly alert you to an impending hazard. Be sure to safely adjust your speed downwards whenever and however you notice rumble devices.
Give directions
Wrong! Whilst some road markings indicate the direction the lane will take you, rumble devices do not indicate directions in any way.
References
In section 6 of the official DVSA guide to driving, it states:
On Page 75 of Know your traffic signs, it states: