At intersections of insufficient importance to require destination signs, a distinctive sign shall be erected at a suitable distance in advance to indicate merely the approach to a minor intersection.
Speed control signs.—Wherever the design of the interregional system provides for maximum safe speed less than 70 miles per hour, the following signs shall be provided:
At the beginning of a section on which the maximum safe speed under normal conditions is between 60 and 70 miles per hour, there shall be erected a sign bearing the legend, “Maximum speed 60,” and signs of this character shall be repeated at approximately 1-mile intervals throughout the section. At such point as a 70-mile speed again becomes safe, a sign shall be erected bearing the legend, “End 60-mile speed.”
At the beginning of a section on which the maximum safe speed under normal conditions is between 50 and 60 miles per hour there shall be erected a sign bearing the legend, “Maximum speed 50,” followed by similar signs at approximately 1-mile intervals throughout the section. At the end of such section one of two signs shall be used, (1) if 70-mile speed is again safe, a sign bearing the legend “End 50-mile speed,” or (2) if the section terminates in a section on which the maximum safe speed is between 60 and 70 miles per hour, a sign bearing the legend, “Maximum speed 60,” followed by similar signs throughout that section.
Where the traffic conditions anticipated at interchanges on rural sections of the system require reduction in speed below 50 miles per hour, the safe speed shall be indicated by a sign erected at the beginning of each such reduced-speed section, bearing the legend “Slow to ——,” with following signs located at appropriate intervals throughout the section, bearing the legend “Speed ——.” The end of such a reduced-speed section shall be marked as above, according to the safe speed permitted by the following section of the highway.
Where State or local traffic regulations, rather than alinement of the highway or traffic conditions, govern the maximum speed, such maximum speed limits shall be indicated at appropriate intervals by signs bearing the legend “Speed limit ——.”
All speed control signs shall be reflectorized for night visibility, except at points where artificial illumination is preferable and feasible.
Signs to control or prohibit passing.—At the beginning of any rural two-lane section of the system on which the sight distance is insufficient for safe passing but more than 1,000 feet, there shall be erected a sign bearing the legend, “Passing unsafe,” and similar signs shall be erected at approximately one-half mile intervals throughout the length of the section.
At the beginning of any rural two-lane section of the system on which the sight distance is less than 1,000 feet, there shall be erected a sign bearing the legend, “No passing.” At the end of such section there shall be erected a sign bearing the legend, “End no passing zone.”
Sections on which passing is unsafe or prohibited shall be indicated independently for each direction.
Pavement markings.—All pavement markings shall be reflectorized.
A. Lane lines: On rural two-lane sections of the system there shall be a continuous 4-inch, white center line. On all four- and six-lane divided sections the lanes shall be defined by 4-inch, white dashed lines.
