OM1-3 Object Marker (Type 1) Sign
Marks an obstruction or hazard within or adjacent to the roadway, using a high-contrast pattern to make the object visible day and night.
| Sign code | OM1-3 |
|---|---|
| Federal code | OM1-3 |
| Name | Object Marker (Type 1) |
| Category | Object Markers |
| Shape | Square |
| Color | Yellow and black diagonal pattern |
| California status | Used in California per CA MUTCD |
| Typical CA minimum size | Per CA MUTCD object-marker standards |
What This Sign Means
Marks an obstruction or hazard within or adjacent to the roadway, using a high-contrast pattern to make the object visible day and night.
California Temporary Traffic Control Use
Used in California to mark fixed objects, equipment, or hazards near the traveled way in and around work zones.
Common TCP Context
- Marking obstructions near the traveled way
- Delineating equipment and fixed hazards
- Supplementing channelizing devices
California Size Requirements
Typical minimum: Per CA MUTCD object-marker standards.
Sizes are CA MUTCD minimums and vary by roadway classification and speed. Verify against the CA MUTCD 2026 (CA MUTCD Part 3F (Object Markers)), Caltrans sign specifications, and the reviewing agency.
Common Placement on a TCP
Where it sits: Advance warning area, ahead of the work.
CA MUTCD reference: CA MUTCD Part 3F (Object Markers).
Los Angeles Area Usage Notes
In Los Angeles, this sign must conform to CA MUTCD 2026. Work in City of LA right-of-way is reviewed by StreetsLA and the Bureau of Engineering (BOE); state highways in LA County are permitted and reviewed by Caltrans District 7; county roads are permitted by LA County DPW. Sizes, retroreflectivity, and placement must meet CA MUTCD minimums — local agencies may require larger signs based on roadway class, speed, pedestrian volume, and proximity to schools or transit.
Common Plan Review Comments
- Object marker omitted on a hazard that remains near traffic.
- Stripe direction does not guide traffic to the correct side.
- Marker type not appropriate for the obstruction.
- Delineation not continuous with the channelizing devices.
Plan Review Notes
Confirm object markers are used on hazards that remain near traffic. Public Ready reviews hazard delineation on the TCP.
Signs Commonly Used Together
These signs are typically deployed alongside OM1-3 on a California TCP.
Rent or Purchase This Sign
Marking roadside hazards? Public Ready can supply object markers and delineation devices.
Official References
- California MUTCD (Caltrans)
Free official resource — opens official government website
- Federal MUTCD (FHWA)
Free official resource — opens official government website
- Caltrans Sign Charts
Free official resource — opens official government website
- FHWA Standard Highway Signs
Free official resource — opens official government website
Educational reference only. This is not an official Caltrans, FHWA, or local agency publication and is not legal or engineering advice. Always verify sign selection, size, placement, spacing, and application against the current CA MUTCD 2026, Caltrans sign specifications, Standard Plans, project documents, and the reviewing agency’s requirements.
Related Signs
Need signs for a California project?
Need to rent, purchase, or include traffic control signs on a California project? Public Ready can help with sign rental, purchase, sign packages, TCP sign legends, and permit coordination.