Which conditions typically require a flagger to direct traffic in a work zone?

• A. During standard office hours
• B. Active work area with moving traffic and one-lane closures
• C. Only when there is a traffic light
• D. When there are no pedestrians

Answer: (B)

When traffic in a work zone is actually moving and lanes are restricted, a flagger is needed to safely guide vehicles and coordinate through-traffic around workers. In an active area with moving traffic and a one-lane closure, signals alone aren’t enough to ensure orderly flow and worker safety, so a flagger provides direct instruction, stops or slows vehicles as needed, and helps pedestrians cross safely when appropriate.

The other situations don’t reliably indicate a need for a flagger. Work zones aren’t limited by office hours; flagging is about active conditions on the road, not the clock. Traffic lights generally control flow, and flaggers are typically used to supplement or override signals only when signals aren’t sufficient or are out of service. The absence of pedestrians doesn’t by itself determine whether flagging is required—the trigger is the combination of moving traffic and lane closures that require direct control.