620.3 Object Markers (MUTCD Chapter 3C)
From Engineering Policy Guide
620.3.1 Object Marker Design and Placement Height (MUTCD Section 3C.01)
Support. Object markers are used to mark obstructions within or adjacent to the roadway.
Standard. When used, object markers (see Object Markers) shall consist of an arrangement of one or more of the following types:
- Type 1 — a marker consisting of all-fluorescent yellow retroreflective diamond panel (OM1-3) 18 in. (450 mm) on a side.
- Type 2 — a marker consisting of an all-fluorescent yellow vertical retroreflective panel, measuring 6 x 15 in. (150 x 375 mm).
- Type 3 — a striped marker, 12 x 36 in. (300 x 900 mm), consisting of a vertical rectangle with alternating black and retroreflective fluorescent yellow stripes sloping downward at an angle of 45 degrees toward the side of the obstruction on which traffic is to pass. The minimum width of the fluorescent yellow and black stripes shall be 3 in. (75 mm).
- Type 3 Modified - a striped marker consisting of the same pattern and color as the Type 3 object marker. Their size, however, is 18 x 18 in. (450 x 450 mm) square and are placed on crash worthy devices within 10 ft. (3 m) of the edge of a lane.
- Type 4 - a marker consisting of an all-red retroreflective diamond panel (OM4-3) 18 in. (450 mm) on a side.
Support. A better appearance can be achieved if the black stripes are wider than the fluorescent yellow stripes.
Type 3 object markers with stripes that begin at the upper right side and slope downward to the lower left side are designated as right object markers (OM-3R). Object markers with stripes that begin at the upper left side and slope downward to the lower right side are designated as left object markers (OM-3L).
Guidance. When used for marking objects in the roadway or objects that are 8 ft. (2.4 m) or less from the shoulder or curb, the mounting height to the bottom of the object marker should be at least 4 ft. (1.2 m) above the surface of the nearest traffic lane.
When used to mark objects more than 8 ft. (2.4 m) from the shoulder or curb, the mounting height to the bottom of the object marker should be at least 4 ft. (1.2 m) above the ground.
See Standard Mounting Heights for Object Markers for standard mounting heights.
Option. When object markers or markings are applied to an object that by its nature requires a lower or higher mounting, the vertical mounting height may vary according to need.
620.3.2 Markings for Objects in the Roadway (MUTCD Section 3C.02)
Support. Obstructions within the roadway, if not illuminated, shall be marked with a Type 1 or Type 3 object marker. In addition to markers on the face of the obstruction, warning of approach to the obstruction shall be given by appropriate pavement markings (see Approach Markings for Obstructions (MUTCD Section 3B.10)).
The object markers shall not be used on traffic signal poles.
Guidance. To provide additional emphasis, large surfaces such as bridge piers should be painted with alternating black and yellow diagonal stripes, 12 in. (300 mm) in width, similar in design to the Type 3 object marker.
Standard. The alternating black and retroreflective flourescent yellow stripes (OM-3L, OM-3R) shall be sloped down at an angle of 45 degrees toward the side on which traffic is to pass the obstruction. If traffic can pass to either side of the obstruction, the alternating black and retroreflective fluorescent yellow stripes (OM-3C) shall form chevrons that point upwards.
If the area of obstruction is too small for the above mentioned marking, standard Type 3 object markers shall be mounted on the object.
Pavement markings shall be used to supplement the standard signs and to guide traffic around the appropriate side of the fixed obstruction. The markings shall be designed to direct traffic away from the obstruction by diagonal lines. These pavement markings shall only be used to supplement the markings on the obstruction itself.
Option. If the obstructing object is such that a Type 3 marker cannot be directly attached, the marker may be installed on a post directly in front of the object.
Appropriate signs (see KEEP RIGHT AND KEEP LEFT Signs (R4-7, R4-7b, R4-8, R4-17) (MUTCD Section 2B.33) and Double Arrow Sign (W12-1) (MUTCD Section 2C.20)) directing traffic to one or both sides of the obstruction may be used instead of the object marker.
620.3.3 Markings for Objects Adjacent to the Roadway (MUTCD Section 3C.03)
Support. Objects not actually in the roadway are sometimes so close to the edge of the road that they need a marker. These include underpass piers, bridge abutments, handrails, and culvert headwalls. In other cases there might not be a physical object involved, but other roadside conditions exist, such as narrow shoulders, drop-offs, gores, small islands, and abrupt changes in the roadway alignment, that might make it undesirable for a road user to leave the roadway, and therefore would create a need for a marker.
Type 3 object makers are used to mark obstructions within the shoulder and/or immediately adjacent to the roadway on two-lane two-way roadways.
Option. Type 2 or Type 3 object markers may be used at locations such as those described in the preceding Support paragraph.
The Type 2 object marker may also be mounted on existing sign posts located in low profile mountable islands and may also be used to delineate stop sign posts. The installation of a Type 2 object marker on the side of the stop sign post is at the discretion of the district office.
Type 3 object markers may be used to mark obstructions on old sections of divided expressway highway not meeting current design standards.
Type 3 object markers may be used on flexible posts at locations where bridge handrails have been lowered to accommodate wide farm equipment.
Standard. If used, the inside edge of the marker shall be in line with the inner edge of the obstruction.
The Type 2 object marker, when used on an existing sign in a low profile island, shall be placed 90 degrees to the face of the existing signs. These markers are to be installed with the 15-inch side in the vertical position, with the bottom of the marker 4 ft. (1.2 m) above the elevation of the roadway surface.
The Type 2 object maker shall not be used at signalized intersections, except if required under temporary conditions, nor to delineate ramps or radii.
Where driving surface narrows, a minimum of three Type 3 object markers shall be used. Spillways on lip type pavement are considered an obstruction and shall be marked with this device and would be located at the shoulder point. See Standard Application of Type 3 Object Markers at Pavement Width Transition for typical layout.
When Type 3 object markers are used on flexible posts at locations where bridge handrails have been lowered to accommodate wide farm equipment, the markers shall be installed approximately 1½ to 2 ft. (0.45 to 0.6 m) above ground level and a minimum distance of 4 ft. (1.2 m) from the bridge end.
The Type 3 object makers shall not be used on the interstate system, on full shoulder width bridges or at obstructions outside the shoulder point.
Guidance. The Type 2 object markers should be mounted on the side of the stop sign post with the object marker being installed such that the bottom of the marker is 4 ft. (1.2 m) above the elevation of the adjacent roadway.
All obstructions depressed or raised between the edge of pavement and shoulder point should be marked with Type 3 object makers.
When Type 3 object markers are used on flexible posts at locations where bridge handrails have been lowered to accommodate wide farm equipment, unless field entrances interfere, standard offsets and spacing for these markers should be used, as shown in Standard Application of Type 3 Object Markers Obstruction Width Less Than Two Feet Wider Than Pavement.
Standard warning signs should also be used where applicable.
Support. When Type 3 object markers are used on flexible posts at locations where bridge handrails have been lowered to accommodate wide farm equipment, the Type 3 object markers at the end of the bridge may be replaced with a Type 3 modified object marker attached to the end of the bridge abutment.
620.3.4 End-of-Roadway Markers (MUTCD Section 3C.04)
Support. The end-of-roadway marker is used to warn and alert road users of the end of a roadway in other than construction or maintenance areas.
Standard. The Type 4 end-of-roadway marker (see Object Markers (MUTCD Fig. 3C-1)) shall be a marker consisting of a retroreflective red diamond panel (OM4-3) 18 in. (450 mm) or more on a side.
Option. The end-of-roadway marker may be used in instances where there are no alternate vehicular paths.
Where conditions warrant, more than one marker, or a larger marker with or without a Type III barricade (see Barricades and Channelizing Devices), may be used at the end of the roadway.
Standard. The minimum mounting height to the bottom of an end-of-roadway marker shall be 4 ft. (1.2 m) above the edge of the pavement.
Appropriate advance warning signs should be used.
| For mounting height details see Standard Mounting Heights for Object Markers |
Standard Application of Type 3 Object Markers Obstruction Width Two Ft. or More Wider Than Pavement
| For mounting height details see Standard Mounting Heights for Object Markers |
620.3.5 Application of Reflective Paint on Bridges (MUTCD Section 3C.05)
Support. Special reflective paint is available from Garage Stock.
Standard. All bridges that require three, Type 3 object markers and other bridges that may be considered vulnerable to impact from traffic due to location or other factors, shall be treated with special reflective paint.
The following general guidelines are to be used in determining the painting required for each type of bridge:
- A. Square Concrete End Posts - Paint shall be applied to all areas of the end posts facing traffic from the top of the post down to 8 in. (200 mm) above the top of the curb (See Typical Application of Reflective Paint on Concrete Bridge Abutments).
- B. Curved Concrete End Posts - Paint shall be applied to all areas of the curved end posts facing traffic from the top of the post down to 18 in. (450 mm) above the top of the curb (See Typical Application of Reflective Paint on Concrete Bridge Abutments).
- C. Angled Concrete End Posts - Paint shall be applied to all areas of the angled end posts facing traffic from the top of the post down to 18 inches above the top of the curb (See Typical Application of Reflective Paint on Concrete Bridge Abutments.
- D. "U Abutment" Concrete End Posts - Paint shall be applied to all areas of the U abutment end posts, the post at the edge of the bridge deck, facing traffic from the top of the post down to 8 in. (200 mm) above the top of the curb. In addition, 3 ft. (0.9 m) of the wing wall rail, starting at the end post, shall be painted (see Typical Application of Reflective Paint on Concrete Bridge Abutments).
- E. Intermediate Posts - Intermediate posts shall be painted with two different methods depending on their design.
- 1. Intermediate posts with components that extend inside of the rail shall receive reflective paint on those portions (See Typical Application of Reflective Paint Along Concrete Bridge Railings).
- 2. Bridges that have intermediate posts that are flush with the inside rail, have a solid concrete parapet wall, or a continuous three-beam rail shall have intermediate areas painted with reflective paint. These areas should be approximately 4 ft. (1.2 m) long and 6 in. (150 mm) high and located on the vertical face of the wall at the top edge (See Typical Application of Reflective Paint Along Flush Bridge Railings). These areas should be spaced using the following guidelines:
- Case I - For bridge lengths over 80 ft. (24 m), the spacing used for the intermediate markings should be between 25 and 40 ft. (7.5 and 12 m). The spacing should provide an even distribution of markings across the bridge.
- Case II - For bridge lengths between 41 and 80 ft. (12.3 m and 24 m), one intermediate painted area shall be marked in the center of the bridge.
- Case III - For bridge lengths less than 41 ft. (12.3 m), no intermediate painted areas shall be provided.
- F. Pipe and Angle Iron Rail - Portions of bridge railings 3 in. (75mm) or less in width, constructed of pipe or angle iron on bridges that do not have a truss structure above the bridge deck shall be painted with reflective paint. The portions that shall receive this paint consist of every 3rd post across the deck and 2 ft. (0.6 m) of the top rail on either side of these posts. These areas shall be painted only on the side facing traffic. The posts shall be painted from the top of the post down to the second pipe, or approximately 1 ft. (0.3 m) down below the top rail. If there are an odd number of posts and the one-third spacing will not work, use an uneven spacing at the end of the bridge (See Typical Application of Reflective Paint on Bridges with Steel Rails).
- G. Steel Channel and Angle Iron Rail - Portions of the channel railings shall be painted with reflective paint. These portions shall include all of the curved end and the first 4 ft. (1.2 m)of the top rail. On these types of bridges which have a concrete end post, the end of the post shall be painted from the top down to a point 8 in. (200 mm) from the top of the curb. The side of the post shall also be painted from the top down a distance of 6 in. (150 mm). Intermediate painted areas shall also be painted along the top rail of these bridges. These areas will be 4 ft. (1.2 m) in length and 6 in. (150 mm) high. The spacing for these painted areas shall be determined using the 3 cases for bridge lengths outlined for intermediate posts previous page (See Typical Application of Reflective Paint on Bridges with Steel Rails).
For truss bridges requiring paint, no member except the batter posts shall be painted.
On divided pavement, only the bridge ends and batter posts facing oncoming traffic shall be painted.
Guidance. Truss Bridges - For truss bridges requiring three, Type III object markers, the surface of all batter posts facing oncoming traffic should be painted. The end batter posts should be painted beginning at a point 2 ft. (0.6 m) above the bridge beck and extending upward to a point 8 ft. (2.4 m) above the bridge deck (vertical measurements). All other batter posts in the truss should also be painted in the same manner, but from a point beginning at the top of the handrail to a point 8 ft. (2.4 m) above the bridge deck (See Typical Application of Reflective Paint on Steel Truss Bridges).
In a case where a pipe or angle iron rail is fastened to members of a truss, every other vertical pipe or angle iron post should be painted. In addition, 2 ft. (0.6 m) of the top rail on either side of these painted posts should also be painted. For bridges requiring paint, intermediate posts or rails that are offset 13 in. (325 mm) or more behind the face of the curb should not be painted.
