1. Road Curves Signs of a Radius larger than 30m
Those signs are placed on the outer side of Curves larger than 30m, in a multiple elements row, having as a sole purpose the ability of the driver to distinguish the Curve from a long distance.
The Sign has a square shape. When placed in roads of a speed limit of 80km/hour, its dimensions are 60*60 cm, while when placed on roads of a greater speed limit, its dimensions are 90*90cm.
The Sign’s shape is consosted from a white arrow on a black background. The width of the white part (measured from the upper to the bottom side of the Sign) is equal to the half of the Sign’s side.
The white colour of the arrow must have high reflectivity and for this purpose are proposed membranes of highest retroreflectivity.
Among the Signs the distance is between 35 and 50m and there are always at least three Signs within the driver’s visual range throughout the road curve.
2. Road Curves Signs of a Radius less or equal than 30m
2.a) For permanent Road Curve Signs of a radius less or equal to 30m is used a rectangular Sign similar to the previous one, however with four times larger bottom side. This Sign should also have high retroreflectivity in order to be instantly observed by drivers.
It is placed vertically to the driver’s visual range.
It is obvious that it is concerned as a major error during construction the possibility of the above stated Sign to be visible from both traffic lanes since it concerns only one of them, and it is possible that it should deceive drivers from the opposite direction, increasing the possibilities of an accident.
Sign dimensions are A=60 and L=240 cm
2.b) For Temporary Road Curves Signs that drive through Construction Sites are used Signs similar in dimensions to ones in 2.a) but with red and white colours instead of black and white.