OM4-1 — Object Marker (Type 4)
Sign Specifications
| Code | OM4-1 |
|---|---|
| Name | Object Marker (Type 4) |
| Category | Object Marker |
| Shape | Marker panel |
| Color | Yellow or orange / black (retroreflective) |
| CA status | Recognized in the California MUTCD (2026) |
| MUTCD reference | § 6F.65 (MUTCD 11th Edition) |
| CA MUTCD reference | California MUTCD (2026) |
What This Sign Means
The OM4-1 Object Marker (Type 4) sign is a retroreflective object-marker panel. It marks an obstruction or the end of a roadway so approaching drivers can see and avoid it, day or night.
California Field Use
- Mounted on or beside obstructions, barricades, and the ends of channelizing devices.
- Provides nighttime delineation with retroreflective material along tapers and hazards.
Where It Goes on a TCP
Activity area — on the obstruction or channelizing device being marked.
MUTCD Requirements
The OM4-1 Object Marker (Type 4) is addressed under Part 6F.65 (object markers) of the MUTCD 11th Edition (MUTCD § 6F.65). Read the governing standard, guidance, option, and support text in the official MUTCD before applying it.
California Requirements
California adopts this sign through the California MUTCD, sometimes with state-specific sizing or application notes. A common conventional-road size is per MUTCD 6F.65; larger sizes apply on expressways and freeways. Confirm the size and application for your facility against the current CA MUTCD (2026) and the Caltrans sign specifications and Standard Plans.
| Application | Standard Size |
|---|---|
| Object marker panel | per MUTCD 6F.65 |
Common Plan Review Comments
- Object markers missing on exposed obstructions or device ends.
- Retroreflective sheeting not specified for night visibility.
- Spacing along the taper not shown.
Compliance Notes
- Markers present on all exposed obstructions.
- Sheeting is retroreflective and clean.
Related Signs
Related Compliance Topics
Learn more in Temporary Traffic Control.
This is an educational reference only. Always verify sign selection, size, placement, and application against the current CA MUTCD 2026, Caltrans sign specifications, Standard Plans, project documents, and the reviewing agency's requirements.