# Road Safety Management of Uncontrolled Access Points:
## 1 Introduction  
Access points are an integral element of the road transport network ensuring the connection between the public roadway and the side properties, private developments, and facilities. However, access is considered one of the main causes of traffic crashes and congestion phenomena [1; 2; 3]. Their location, design, and visibility conditions are often associated with several issues that are inconsistent with the required safety standards related to the vehicles and pedestrians' mobility. Furthermore, their low safety performance is generally due to left-turn movements, in or out. [PERSON] [4; 5], the author of a comprehensive study on driveway crashes categorised by manoeuvre and type of collision, found that more than 65% of driveway-related accidents involved vehicles turning left into the driveway. Some studies reported that about 5% of crashes that occurred in urban areas can be expressly related to the presence of access points; this same percentage is estimated to be equal to 7% for the rural context [6; 7]. An increase in the access density of an additional access point per kilomet results in an increase in the accident rate (approximately 1.5%) for two-lane roads in both urban and rural areas [8; 9]. Several studies found that the crash rate is associated with the square root of access density [1; 10]. [PERSON] et al. [11] observed a decrease in the injury severity of crashes that occurred in high-density residential areas: the reduction in the likelihood of recording a serious accident is about 12%, and the causes are mainly due to the lower operating speed in this environment. Intersection areas are characterised by speed differential; according to some studies, the exponential growth in the likelihood of collision is related to the increase in the speeddifferential between the through-traffic flow and the turning vehicles [12]. The conflict analysis carried out by [PERSON] et al. [13] using the surrogate safety assessment model (SSAM) highlighted the three factors influencing collisions at access points: speed, volume, and driveway spacing; in particular, the authors observed that by keeping the first two variables constant, the increase in the driveway distance resulted in a substantial reduction in the number of conflicts. Higher operating speed and traffic driveway volumes require an increase in the distance between two successive connections [14]. A recent analysis by [PERSON] et al. [15] reveals that a 457 veh/day increase in access volume translates into a 7% increase in crash rate. Uncontrolled access point design affects the safety of motor vehicle drivers, bicyclists, and pedestrians [16]. The main design criteria must follow the basic principles which are common for the design of every element of the road infrastructure: (i) the project should mitigate the occurrence and consequences of traffic crashes in the intersection area; (ii) design choices should maximize the safety level and operational performance (delay times, travel times, comfort). The configuration of the intersection impacts the risk of a collision, given the high potential of conflict between turning vehicles and the through-traffic flow. The key geometric elements that must be addressed are the following: the intersection angle between the side access and the main roadway, the curb radius, the access width, and access spacing. In particular, the interaction between width and radius affects both vehicle speed and path [17]. The configuration including a small width and radius should be avoided (if the width is reduced, the radius should be increased and vice versa) [17]. A higher width facilitates circulation and turning manoeuvres when these conditions cannot be guaranteed by an appropriate radius dimension. However, [PERSON] et al.