Markings on highways have important functions in providing guidance and information for the road use.  Major marking types include:

• pavement and curb markings
• object markers
• delineators
• colored pavements
• barricades
• channelizing devices
• islands

In some cases, markings are used to supplement other traffic control devices such as signs, signals and other marking, while other times markings are used alone to effectively convey regulations, guidance or warnings in ways not obtainable to the use of other devices.

Pavement markings can enhance roadway delineation with the addition of audible  and tactile features such as bars, differential surface profiles, raised pavement markers  or other devices intended to alert the road user that a delineation on the roadway is being traversed.

A "No-Passing Zone" at a horizontal or vertical curve is warranted where the sight distance as defined in Section 3B-5 of the Ohio Manual of Uniform  Traffic Control Devices (OMUTCD) is less than the minimum necessary for safe passing at the prevailing speed of traffic.

No-Passing  Zones may be marked at rural and urban intersections where an engineering judgment so dictates.  The decision as to whether or not a No Passing Zone should be marked is a matter of discretionary engineering judgment.  There is explicitly no requirement under the OMUTCD that No-Passing Zones shall be marked at intersections, notwithstanding the provisions of any other section of the OMUTCD.