Anchor: #i1003737

Section 2: Object Markers

Anchor: #i1003743

Introduction

Object markers use retroreflective material to indicate to the driver the presence of an object or obstruction within or adjacent to the roadway. In addition to marking the object or obstruction, some object markers also indicate the side to which a driver should pass. Typical obstructions where object markers may be used include bridge ends, guardrail end treatments, culvert headwalls, and other obstructions within the right-of-way.

Anchor: #i1003753

Types of Object Markers (Texas MUTCD, Section 2C.63)

There are four types of object markers as described below and illustrated in Figure 8-1.

    Anchor: #NIVACWTL
  • Type 1 Object Marker: A yellow diamond-shaped panel consisting of all retroreflective sheeting (OM1-3).
      Anchor: #QADXQARN
    • The minimum size of the OM-1 is 18 x 18 inches.
      • Anchor: #UDGRFXWM
    • The bottom of a Type 1 object marker should be 4 ft above the edge of the travel lane and is mounted on thin-walled tubing.
    • Anchor: #IVKFHHSD
  • Type 2 Object Marker: A yellow rectangle or series of three yellow reflectors.
      Anchor: #BQAVGRYY
    • OM2-X: A series of three yellow retroreflectors. The minimum size of each retroreflector is 4 x 4 inches. OM-2X is mounted on wing channel post.
      • Anchor: #MESAHOUI
    • OM2-Y: A yellow rectangular panel consisting of all retroreflective sheeting. The minimum size of the panel is 6 x 12 inches. OM-2Y is mounted on wing channel post.
      • Anchor: #WPAHSJCS
    • OM2-Z: A series of three yellow retroreflectors or a single larger yellow retroreflector. The minimum size of each retroreflector is 3 x 4 inches when used in a series of three. For a single retroreflector, the minimum size is 3 x 12 inches. OM2-Z is mounted on a flexible post.
      • Anchor: #UWDWKGRM
    • The Type 2 object marker is usually mounted with a vertical orientation.
      • Anchor: #TYRHHHJB
    • The bottom of a Type 2 object marker is mounted at a height of approximately 4 ft. If the object marker is within 8 ft of the edge of pavement, the mounting height is above the edge of the travel lane. When the object marker is more than 8 ft from the edge of pavement, the mounting height is above the ground. Higher or lower mounting heights can be used according to need.
    • Anchor: #LTBYFHQV
  • Type 3 Object Marker: A vertical rectangle with black and yellow diagonal stripes.
      Anchor: #JVPCGYNW
    • OM-3L: An object marker with diagonal stripes oriented from the top left to lower right. The OM-3L is located on the left side of the road.
      • Anchor: #QWHPFPBW
    • OM-3C: An object marker with diagonal stripes oriented from the center downward to the left and right. The OM-3C is located in the roadway when vehicles can pass on both sides of the object marker.
      • Anchor: #LRTNPHRC
    • OM-3R: An object marker with diagonal stripes oriented from the top right to lower left. The OM-3R is located on the right side of the road.
      • Anchor: #IAKKIGHB
    • All versions of the Type 3 object marker have a minimum size of 12 x 36 inches and are mounted on thin-walled tubing.
      • Anchor: #OLETXEDP
    • The bottom of a Type 3 object marker is located at approximately 4 ft above the edge of the travel lane.
    • Anchor: #WHOHKERT
  • Type 4 Object Marker: A red diamond-shaped panel consisting of all retroreflective sheeting (OM4-3).
      Anchor: #PYBMGBEV
    • The minimum size of OM-4 is 18 x 18 inches.
      • Anchor: #LJQXXRVY
    • Type 4 object markers are used to mark the end of a roadway, and are usually combined with a barricade (see Texas MUTCD Section 2C.66).
      • Anchor: #AHBKFBJF
    • When ground mounted, OM-4 is mounted on thin-walled tubing 4 ft above the near edge of the traveled way.

Object Markers (click in image to see full-size image) Anchor: #SKGKYNJLgrtop

Figure 8-1. Object Markers

Anchor: #i1003859

Omni-Directional Sign Post Wrap

A sign post wrap consists of yellow or red retroreflective sheeting wrapped around a sign post to identify the support as a roadway object.

    Anchor: #RVVFNSBE
  • Retroreflective sheeting wrapped around a sign is yellow unless the sign on the support is a Stop or Yield sign, in which case the sheeting is red.
    • Anchor: #ERKAVIAG
  • Retroreflective sheeting wrapped around a sign has a height on the post of at least 12 inches.
    • Anchor: #DALKNYWJ
  • The bottom of retroreflective sheeting wrapped around a sign is approximately 4 ft above the edge of the travel lane (see Texas MUTCD Section 2A.21).
Anchor: #i1003884

Application of Object Markers (Texas MUTCD, Section 2C.65)

Figure 8-2 shows how guardrail end treatments are marked with object markers. Note that when the energy absorbing treatment is used, a post mounted object marker is not required if a guardrail end treatment object marker is built into the side of the treatment facing traffic.

Object Marker at Energy Absorbing Treatment (EAT) (click in image to see full-size image) Anchor: #ICHVLAWFgrtop

Figure 8-2. Object Marker at Energy Absorbing Treatment (EAT)

Object Marker at Turndown (Texas Twist) (click in image to see full-size image) Anchor: #MBADFCOKgrtop

Figure 8-3. Object Marker at Turndown (Texas Twist)

See Table 8-1 for various object marker applications.
Previous page  Next page   Title page