Often you will want to plot accidents along a route as route based remedial measures can be very effective. Once you have identified a length of road to be treated it is helpful to identify the location of all accidents along that route. Where the cluster such as at junctions, plotting the location symbols at a size at which their details are readable, means they often overlap, but to avoid this by reducing their size can mean they are less readable.
The best approach to this is to assume initially that the symbols will not overlap so that you can ensure they are plotted at the correct, readable size, for example if the road is several miles, and this is to be plotted onto A1 size paper. Where the accidents cluster, for example at junctions or other collision ‘hot spots’ they will most likely overlap and would be better if separated and drawn with a leader to the recorded location of the collision.