OM1-3 Object Marker (Type 1)
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 Name
- Object Marker (Type 1)
- General Meaning
- Marks an obstruction or hazard within or adjacent to the roadway, using a high-contrast pattern to make the object visible day and night.
- MUTCD Code
- OM1-3
- Typical Use
- At (or leading up to) the obstruction it marks, per CA MUTCD object-marker standards.
- Sign Category
- Object Markers
Specifications
- Standard Shape
- Square
- Background Color
- Yellow And Black Diagonal Pattern
- Legend / Symbol
- Black legend
- Border
- Black
- Reflectivity
- High Intensity (for nighttime visibility)
- Compliance
- MUTCD / CA MUTCD
Standard Sizes (inches)
- 24 in Square24" × 24"
- 30 in Square30" × 30"
- 36 in Square36" × 36"
- 48 in Square48" × 48"
Material / Application Notes
Marking obstructions near the traveled way. Confirm placement and supplemental plaques against the applicable CA MUTCD standard.
View this sign on the Federal MUTCD (FHWA)California Notes
California-specific application notes and adoptions may differ. Review California requirements where applicable.
What It Means / When This Sign Is Used
In the field, OM1-3 Object Marker (Type 1) is typically positioned at the at (or leading up to) the obstruction it marks, per ca mutcd object-marker standards. Common deployments include marking obstructions near the traveled way; delineating equipment and fixed hazards; supplementing channelizing devices. Always confirm its size, retroreflective sheeting, spacing, and placement against the CA MUTCD 2026 and the reviewing agency before finalizing the traffic control plan.
Learn more about Object Marker (Type 1) sign requirementsWhen & Where It's Used
- Marking obstructions near the traveled way
- Delineating equipment and fixed hazards
- Supplementing channelizing devices
Placement on a Traffic Control Plan
- Where it sits
- At (or leading up to) the obstruction it marks, per CA MUTCD object-marker standards.
- CA MUTCD reference
- CA MUTCD Part 2, Chapter 2C (Warning Signs and Object Markers)
- Typical minimum size
- Per CA MUTCD object-marker standards
California / Field Use Notes
Used in California to mark fixed objects, equipment, or hazards near the traveled way in and around work zones.
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.
Confirm object markers are used on hazards that remain near traffic. Public Ready reviews hazard delineation on the TCP.
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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. Local jurisdictions may impose additional requirements, and final selection, placement, and dimensions may require engineering judgment or agency approval. Written against California MUTCD 2026 (effective January 18, 2026) and the Federal MUTCD 11th Edition. Official sources last verified June 2026.
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