What speed bumps should be like and how to report those that are illegal

Some of the great enemies of cars and drivers are speed bumps. This is how road bumps are popularly known, the objective of which is to maintain a reduced traffic speed in some areas. It has been proven that, in the long run, they cause damage to vehicles and have to be comply with regulations to be legal. We are going to analyze the different types of speed bumps that exist, what they should be like and also how to report those that are illegal.

The first thing to say is that these “speed reducers (RDV)”, which is their official name, are another instrument of the DGT to fight against speeding. Technically, they are projections that cause a vertical acceleration in cars that pass over and that transmits “discomfort to drivers and occupants when driving at speeds higher than those established.” Also going slower, but that is another debate to open.

Types of speed bumps and measurements

There are two main types of speed reducers:

trapezoidal cross section

This type of speed bumps, also known as praised pedestrian walkways They serve as zebra crossings, their grade being at a level slightly higher than that of the road. In this way, it is possible to reduce speed in those very sensitive areas with traffic of people. For these highlights we see that there are two ramps (entrance and exit) and a kind of plateau between them, hence the trapezoidal section.

By law, they have to have 10 centimeters high (1 cm margin), with a length of the raised area of ​​4 meters (20 cm margin). There is talk that there are exceptional cases with lengths of 2.5 meters, which have to be approved. Also that the length of the ramps must be between 1 and 2.5 meters depending on maximum speed of the road. It will be 1 meter for a 30 km/h limitation, 1.5 meters for 40 km/h roads and 2.5 meters for 50 km/h roads. The leading edge must be a maximum of 5 mm.

donkey loin

Also known as speed bumps circular segment cross section for its shapes. Those that are manufactured “in situ” directly on the pavement must have a height of 6 centimeters (with 1 cm margin) and a length of 4 meters (20 cm margin). In the case of prefabricated ones, it depends on the maximum speed allowed on the road they are going to be installed:

  • Maximum speed of 50 km/h – Less than 3 cm in height and more than 60 cm in length
  • Below 50 km/h – Between 5 and 7 cm in height and between 60 and 120 cm in length

In any case, the entrance edge between the road and the speed bump must be maximum 5 mm high so that it does not affect the vehicles that face it so negatively.

Where can speed bumps be placed?

It is important to know the two main types of speed bumps and their measures to report if there is any illegality. It is also important know where they can be located. They are only indicated for those roads where the speed should be lower, but other measures such as signs or roundabouts have not worked. They are areas limited between 30 and 50 km/hmaking it unthinkable for them to appear on faster roads.

The distance between speed bumps that are followed must be between 50 and 200 meters, trying not to exceed 150 meters. They are prohibited in some cases, such as in the first 50 meters of the entrance to the crossing, in those that are shorter than 200 meters, in sections with slope greater than 5%roads with more than two traffic lanes (without median) or near intersections (for those with donkey backs).

They must also be correctly indicated by the relevant signage. Raised pedestrian crossings must have transverse white bands in their central part and end in triangles on the ramps. With the donkey back ones you have to put three white triangles on the ascending part. Vertical signs are necessary such as signal P-15a, which is specific to speed bumps, maximum speed or pedestrian danger. These areas must have night lighting.

How to report illegal speed bumps

All speed reducers must comply with the stipulated regulations. If they are not within the measures that have been indicated, if they appear in places where they should not or without proper signage, they could be reportable illegal speed bumps. To report them, it would have to be done to the body that owns the road, which is usually the city councils because the majority are located in urban centers.

Although you could also report to the special road safety prosecutor’s office. That would be reserved for those cases that could be a criminal offense or that accidents could occur due to having an illegal speed bump in that place.

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