Temporary traffic-control warning signs generally use a black legend and border on an orange background. Common families include W20 road-work and closure warnings, W21 worker and maintenance warnings, W22 blasting warnings, W23 traffic-condition warnings, W24 temporary alignment warnings, and G20 work-zone guide signs.
At a glance
| Series | Typical subject | Examples |
|---|---|---|
| W20 | Work, closure and traffic-control approach | ROAD WORK, DETOUR, ROAD CLOSED, ONE LANE ROAD, FLAGGER |
| W21 | Workers and maintenance activity | Workers, shoulder work, utility work, mowing |
| W22 | Blasting zones | Blasting-zone approach and end messages |
| W23 | Changed traffic conditions | Slow traffic, new traffic pattern, new signal operation |
| W24 | Temporary alignment | Temporary double-reverse curves and lane plaques |
| G20 | Work-zone guide information | Work limits, end road work and project information |
A work-zone sign is one part of a plan
Signs, channelizing devices, markings, arrow boards, flaggers, barriers, and other devices work together under a temporary traffic-control plan. Selecting an orange sign without considering the complete sequence and roadway context is not a substitute for that plan.
Not every warning near work is orange
The current MUTCD specifies exceptions and cross-references for particular devices. For example, the highway-rail grade-crossing advance warning retains its required warning color. Always verify the exact device rather than recoloring a standard sign by assumption.
Browse work-zone designations
The Sign Library groups 38 temporary traffic-control signs from the W20–W24 and G families. Search by a phrase such as “road work,” “flagger,” “lane closed,” or “utility work” to narrow the list.
Work-zone equipment resources
After identifying the applicable sign, crews can source roll-up work-zone signs, temporary sign stands, and traffic cones from Work Zone Supply.
Frequently asked questions
What color are work-zone warning signs?
They generally use a black legend and border on an orange background, subject to provisions for specific devices.
What does W20 mean?
W20 is the warning-sign series that includes common road-work, detour, closure, lane-closure, and flagger approach signs.
Can a work-zone sign stay up permanently?
Temporary devices should reflect current conditions and be removed or covered when they no longer apply, consistent with the temporary traffic-control plan and agency requirements.