A. The following radii be established for intersections of curblines to minimize danger and avert congestion of traffic.
B. The radii of the circular areas of curblines connecting the adjoining straight or tangent curblines at points of projected intersection, in all cases, shall be those of tract circles and the lengths of such radii to be governed as follows:
(1) Curblines which intersect at an angle of 90° or right angle and which are:
(a) Adjacent to sidewalks, either of which is greater than 10 feet in width, shall be joined at such intersection by a circular arc, the radius of which shall be eight feet.
(b) Adjacent to sidewalks which are between 6 1/2 feet and 10 feet, inclusive, in width, shall be joined at such intersection by a circular arc, the radius of which shall be six feet.
(c) Adjacent to sidewalks which are between two feet and 6 1/2 feet, inclusive, in width, shall be joined at such intersection by a circular arc the radius of which shall be three feet.
(2) Curblines which intersect at an angle other than 90° or a right angle shall be joined at such intersection by simple circular arcs the radius of which shall be determined as described on Plan No. C-77 of the Department of Public Works of the City of Reading, entitled "Plan Illustrating Rule for Determining Curb Radii," dated April 1916, which shall be on file in the office of the Director of Public Works.