Work-Zone Traffic Control
Most C-12 paving and roadway work happens next to live traffic, so the exam’s safety section includes work-zone traffic control from the California MUTCD (Part 6) — the same public-domain rules behind the C-31 trade.
The essentials
Orange = work-zone signs. Taper length: ≥ 45 mph → L = WS; ≤ 40 mph → L = WS²/60. The STOP/SLOW paddle is the flagger’s primary device. Channelizing devices on a taper are spaced no more than 1 × the speed limit (in feet); on a tangent, 2 × the speed limit.
A temporary traffic control zone has four areas — advance warning, transition (the taper), activity (work space and buffer), and termination (END ROAD WORK). For the full set of signs, devices, flagging procedures, and message-sign rules, see the dedicated C-31 Construction Zone Traffic Control exam.
Practice: Work-Zone Traffic Control
Frequently asked
What color are work-zone signs?
What is the taper-length formula in a work zone?
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