Summary
Crashes involving lorries turning right and cyclists going straight ahead usually have very serious consequences for the cyclist. The cyclist, who has right of way, is often overlooked by the lorry driver. For his part, the cyclist is often unaware that the lorry driver has not seen him or that the driver wants to turn right. Despite a variety of measures, this type of blind spot crashes continues to occur. Each year they still cause approximately ten fatalities. This number could be reduced in the long term by banning heavy goods vehicles from town centres. In the short term, possible measures are: more information about the blind spot in the driver training and permanent public information for cyclists about how to behave in blind spot situations: the ‘code of behaviour’. More research into the (far reaching) separation of heavy freight traffic and cyclists in the long term is necessary, as well as into reliable detection systems to support the lorry driver in his driving task.
Background and content
Due to the size of a lorry the driver has poor vision around the vehicle and encounters difficulties in manoeuvring in the town/city. The size of the vehicle also means that if a crash occurs, the crash opponent usually is severely injured. More information about lorries in traffic can be found in SWOV fact sheet Lorries and delivery vans. Dangerous situations occur when the lorry wants to turn right in an urban area and cyclists are located to the right or in front of the vehicle. Legally speaking, the cyclists have the right of way but they are overlooked by the driver. Because blind spot crashes appear to be avoidable and the consequences for the casualties are very severe, this type of crash attracts considerable media attention.
This fact sheet will discuss the concept ‘blind spot’, look at the data in relation with the blind spot issue and suggest possible solutions for this problem.
Where is the blind spot of a lorry? The formal definition of the blind spot is the area around the lorry which cannot be seen, directly or indirectly, by the driver. A direct view exists if the driver can see the area through one of the vehicle windows. An indirect view is what the driver can see via mirrors or cameras. Therefore, the size and position of the blind spot depends on the type of lorry, including the height of the cab and the presence of mirrors or cameras. This fact sheet will only deal with the blind spot which occurs when turning right. Figure 1 shows the areas that must be visible to the driver according to current EU Directives. It also shows where different mirrors are attached to the cab of the lorry. Lorries marketed since 2007 are equipped with a front view mirror, a more convex kerb mirror and a more convex wide angle mirror than on older lorries. These mirrors can cover a larger area than the blind spot mirror (as shown in the photograph) and thus make it unnecessary.
A lorry driver who has adjusted his mirrors correctly will have the field of vision shown in Figure 1. The blind spot relevant to lorries turning right is, on vehicles built up to and including 2006, located on the right hand side, just in front of the cab. For lorries with a high cab, this spot is not visible through the window, nor by making use of the blind spot mirror or the wide angle mirror. For new lorries built after 2007, the largest part of the area to the right and the front right of the lorry is visible for the lorry driver when the mirrors are properly adjusted. This shifts the blind spot problem from physical visibility towards task burden or attention: it is impossible for the driver to look through all windows, in all mirrors and at the cameras simultaneously. This has the consequence that vulnerable road users still run the risk of being overlooked, despite all the mirrors. In addition, the direct view may also be obstructed by door posts, mirrors and objects that are placed on the dashboard.