Reflective Pavement Markers are most commonly seen in the center of the roads to indicate separation of lanes.
Usage of color
- White markers — for lane markings or to mark the right pavement edge.
- Yellow or orange markers — These separate traffic moving in opposite directions, or mark the left pavement edge on one-way roadways.
- Blue markers — Usually placed in the center of the roadway to mark the location of fire hydrants on the shoulder or at the curb.
- Green markers — Usually used to indicate that emergency vehicles can open gates to enter a gated community.
- Red markers — Usually indicate areas that are closed to traffic. Red-Clear Markers are primarily used to warn motorists they are going the wrong way; most people have never seen these because they show clear when headed in the correct direction, and only appear red to wrong way drivers.
Colors can also be combined, with a different color facing each direction:
- White and red or yellow and red — white or yellow for normal use in one direction, and red to indicate “do not enter” or “wrong way” in the other direction
- White and black — white for marking lane restrictions (such as an HOV diamond) in one direction on a roadway that has “reversible” traffic flow, and black in the other direction when the markings don’t apply
The current trend for lane markings is to intersperse retroreflective paint lines with reflectors as seen on the majority of American highways.”