Work-Zone Speed and Flagger Control on a Two-Lane State Highway
You are driving a pickup southbound on a two-lane Mississippi state highway at 7:40 a.m. The posted limit is 55 mph. An orange ROAD WORK AHEAD sign appears, followed by a SPEED LIMIT 45 sign with a WORK ZONE plaque. Beyond the taper, a flagger holds a STOP paddle while a pilot car waits. The lane is narrowed by cones on the right. Your passenger says the 45 sign is only a suggestion because no workers are visible. You are 12 minutes late for a meeting. The flagger turns the paddle to SLOW and waves you forward, but the pilot car has not moved. A second sign past the flagger station reads SPEED LIMIT 35 with a WHEN FLASHING plaque, and its yellow beacon is dark.
1. What speed limit is enforceable before the flagger station, and does the 45 sign remain controlling after you pass it if no workers are visible? Explain.
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The 45 sign with the WORK ZONE plaque is a regulatory speed limit, not an advisory. It is enforceable from the point where it is posted until another regulatory sign changes it or the work-zone restriction ends. The absence of visible workers does not make it optional; work-zone speed limits often apply whenever the zone is posted, because workers or equipment may be just out of view or may return without warning. After you pass the sign, 45 mph remains the controlling limit unless a different sign, a flagger, or the end of the work zone changes it. The 35 sign with WHEN FLASHING is conditional: if the beacon is dark, 35 is not active. Even so, the basic speed law still requires you to drive no faster than is safe for the narrowed lane, rain, and traffic queue.
2. The flagger waves you forward while the pilot car is stopped. What should you do, and why?
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A flagger's direction is regulatory and can override the normal sign sequence, but a wave does not necessarily mean pass the pilot car. Move forward only as directed, and stop before the taper or behind the pilot car if it has not entered the work zone. The pilot car controls movement through the one-lane section; passing it or entering the closed lane would put you in conflict with oncoming controlled traffic and with workers. If the flagger clearly signals you to follow the pilot car and the path is clear, proceed at or below 45 mph with extra gap. Until then, hold your position and do not treat the wave as permission to ignore the pilot car.
3. If the yellow beacon on the 35 sign begins flashing after you pass the sign, are you required to slow to 35, and what if you are already past it?
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If the beacon begins flashing while you are approaching and the sign is still ahead of you, the conditional regulatory limit becomes active and you must slow to 35 mph. If you have already passed the sign when it starts flashing, you are not required to reverse or treat the sign as applying behind you; the next posted sign or the end of the work zone controls. However, a flashing beacon is a warning that conditions may have changed, such as equipment entering the lane or workers present, so you should reduce speed and increase following distance regardless. A flagger's signal or an obvious hazard still takes priority over the posted number.