Work Zone and Temporary Traffic Control Signs
Work zone signs are temporary, orange and change fast. The exam tests the four parts of a temporary traffic control zone, the authority of a flagger, and how a posted work-zone speed limit differs from an advisory speed. Orange means people are working near the travel lane; the sign's job is to move you out of the way before you reach them.
The four areas
Advance warning area: signs such as ROAD WORK AHEAD or LANE CLOSED AHEAD tell you what is coming. Transition area: cones, drums or barricades taper traffic out of the closed lane. Activity area: the buffer space, the work space and the traffic space where you actually drive. Termination area: where traffic returns to normal. Signs remain in force until the termination area even when no workers are visible.
Flaggers and devices
A flagger with a STOP/SLOW paddle has the authority of a sign: STOP means stop and stay stopped; SLOW means proceed slowly and be ready to stop. Portable traffic signals and arrow boards do the same job. Channelizing devices - cones, drums and tubular markers - mark the path; do not drive over them, and do not cross a solid line of drums.
Speed in work zones
A white speed limit sign posted in a work zone is enforceable like any other limit, and it is usually lower than the normal limit. Fines for moving violations in work zones can be higher than normal, and workers do not have to be present for the zone to be in effect if the signs are posted.
Worked example
A driver sees ROAD WORK AHEAD, then a flagger showing SLOW, then a 25 MPH sign where the normal limit is 35. The driver should slow to 25, proceed past the flagger, stay in the marked lane, and not accelerate until a sign or the end of the taper shows the zone has ended. The flagger controls the lane, the posted sign sets the legal speed, and the drum taper defines where the lane is.
Traps
Resuming speed right after passing the workers; passing a flagger; assuming the zone is inactive because no equipment is visible; and missing a temporary lane shift that puts you closer to oncoming traffic.