Image of a Object Marker (OM1-3) OBJECT MARKER (OM1-3)
The Object Marker (OM1-3) shall be authorized for use to mark obstructions located within the roadway such as bridge piers, and the end of islands.  This marker may be posted with other signs where appropriate.

The OM1-3 marker is a 18 inches x 18 inches yellow reflectorized blank.
Image of a End Of Roadway Marker (OM4-3) END OF ROADWAY MARKER (OM4-3)
The End Of Roadway Marker (OM4-3) shall be authorized for use to mark the end of a roadway at the point where there is no alternate vehicular path.

The OM4-3 marker is a 18 inches x 18 inches red reflectorized blank.
Image of a Left Clearance Marker (OM-3L) LEFT CLEARANCE MARKER (OM-3L)
(a) Justification.  The Left Clearance Marker (OM-3L) may be used to delineate bridge abutments, parapets, handrails, underpass piers, and culvert headwalls within or adjacent to the roadway where traffic is required to pass to the right of the obstruction or object.

(b) Placement.  The right edge of the OM-3L marker shall be in line with the right edge of the obstruction or object.  When used at bridges with a wheel guard, the right edge of the marker should be in line with the right edge of the wheel guard.  The bottom of the marker should be at a height of 3 feet to 5 feet above the near edge of the pavement.
Image of a Right Clearance Marker (OM-3R) RIGHT CLEARANCE MARKER (OM-3R)
(a) Justification.  The Right Clearance Marker (OM-3R) may be used to delineate bridge abutments, parapets, handrails, underpass piers, and culvert headwalls within or adjacent to the roadway where traffic is required to pass to the left of the obstruction or object.

(b) Placement.  The left edge of the OM-3R marker shall be in line with the left edge of the obstruction or object.  When used at bridges with a wheel guard, the left edge of the marker should be in line with the left edge of the wheel guard.  The bottom of the marker should be at a height of 3 feet to 5 feet above the near edge of the pavement.