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-style sign reference illustration. Always verify against the official CA MUTCD and Caltrans sign charts.
| 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 |
Download this sign or open the official MUTCD reference.
Official source: FHWA Standard Highway Signs, 2024 (11th Edition) — Object markers.
Source: FHWA Standard Highway Signs — Public Domain. California: CA MUTCD 2026 (effective Jan 18, 2026).
Files linked from FHWA are official government publications in the public domain. CA MUTCD and Caltrans links open official government websites. Always verify against the current edition.
Marks an obstruction or hazard within or adjacent to the roadway, using a high-contrast pattern to make the object visible day and night.
Marks an obstruction or hazard within or adjacent to the roadway, using a high-contrast pattern to make the object visible day and night. In the field, OM1-3 Object Marker (Type 1) is typically positioned at the advance warning area, ahead of the work. 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.
Used in California to mark fixed objects, equipment, or hazards near the traveled way in and around work zones.
Common field deployments
Agency review note
StreetsLA, LA County DPW, and Caltrans District 7 may require larger sizes or additional devices. Verify with the reviewing agency before finalizing the TCP.
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.
Where it sits: Advance warning area, ahead of the work.
CA MUTCD reference: CA MUTCD Part 3F (Object Markers).
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.
Confirm object markers are used on hazards that remain near traffic. Public Ready reviews hazard delineation on the TCP.
These signs are typically deployed alongside OM1-3 on a California TCP.
Marking roadside hazards? Public Ready can supply object markers and delineation devices.
Free official resource — opens official government website
Free official resource — opens official government website
Free official resource — opens official government website
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.
To understand the bigger picture around permits, agency review, lane closures, and pedestrian access for work zones using OM1-3 Object Marker (Type 1), visit WorkZoneCompliance.com.
Public Ready can help with OM1-3 Object Marker (Type 1) — including sign rental or purchase, work-zone signs, TCP sign legends, and permit coordination, and agency-review support for Caltrans District 7, the City of Los Angeles, and LA County.
