Construction and Work Zone Signs: Orange Devices, Flaggers, and Lane Shifts
Construction and work-zone signs use orange to separate temporary conditions from permanent yellow warnings. The Missouri exam tests whether you recognize orange devices, understand a flagger's authority, and know how to respond to lane shifts and temporary traffic patterns.
Core rules
- Orange diamond signs warn of work ahead, such as road work, lane closure, or a flagger. Orange rectangles can be regulatory, including temporary speed limits.
- Flaggers direct traffic with a STOP/SLOW paddle or hand signals. A flagger's direction overrides posted signs and signals; slow or stop as instructed.
- Lane shifts are shown by arrow boards, cones, barrels, and temporary pavement markings. Stay in your lane and follow the taper; do not change lanes inside the work area unless directed.
- Work-zone speed limits are enforceable regulatory limits. Missouri imposes enhanced penalties for moving violations in active work zones when workers are present.
- Pilot cars lead traffic through a one-lane work zone. Follow at a safe distance and do not pass the pilot car.
Worked example
A flagger holds a STOP paddle as you approach a one-lane bridge repair. Even if the permanent signal is green or no other cars are visible, you must stop and wait for the flagger to turn the paddle to SLOW or wave you through. The flagger is controlling the temporary traffic pattern.
Traps
Orange speed-limit signs are not suggestions. Do not tailgate a pilot car or the vehicle ahead in a work zone. A "ROAD WORK AHEAD" sign does not mean the lane is already closed; watch for the actual taper and arrow board. Ignoring a flagger can cost marks and points.