Work Zone Compliance Guide for Flaggers

A flagger controls traffic directly, standing close to it, which makes readiness and position central to the role. This guide outlines what a flagger needs in place before controlling traffic.

Last reviewed: June 24, 2026

What This Role Owns

  • Being trained for the task per the applicable requirement.
  • Wearing high-visibility apparel appropriate for the conditions.
  • Standing in a visible position with a planned escape path.
  • Coordinating with other flaggers so traffic is controlled safely.

Before Controlling Traffic

A flagger's safety starts before the first vehicle. Confirm training, apparel, the signaling device, and that flagger-ahead advance warning is in place upstream.

  • Confirm you are trained for the task.
  • Wear high-visibility apparel and use the correct signaling device.
  • Confirm flagger-ahead advance warning signs are placed upstream.

Position and Coordination

Where a flagger stands, and how flaggers coordinate, keeps both workers and drivers safe. Keep visibility to approaching traffic and a clear escape path, and never release one lane from both ends.

  • Stand where approaching traffic can see you, with an escape path.
  • Coordinate with other flaggers so a lane is released from only one end.
  • Confirm lighting is adequate if flagging at night.

Common Pitfalls for This Role

  • Flagging without the required training.
  • Standing where approaching drivers cannot see the flagger in time.
  • Having no planned escape path from traffic.
  • Two flaggers releasing the same lane from both ends.

Checklists for This Role

Related Pages

Frequently Asked Questions

What does a flagger need before controlling traffic?

Generally: training for the task, high-visibility apparel, the correct signaling device, flagger-ahead advance warning upstream, a visible position, and a planned escape path. Specific requirements come from the applicable standard and the approved plan.

Why must flaggers coordinate on a one-lane setup?

On alternating one-lane traffic, if two flaggers release the same lane from both ends, vehicles can meet head-on. Coordinating so the lane is released from only one end at a time is a core part of safe flagging.

Need Project-Specific Support?

Work Zone Compliance provides general educational information. For project-specific traffic control plan support, permit coordination, or public right-of-way planning in Southern California, visit Public Ready.

Visit Public Ready