What type of device is used for automated flagging in construction zones?

The correct answer is AFAD, which stands for Automated Flagger Assistance Device. AFADs are designed to enhance safety and efficiency in construction zones by automatically managing traffic control. They typically include a stop/slow sign that can be operated remotely or triggered by sensors. The use of AFADs helps reduce the need for human flaggers on the site, thereby decreasing potential exposure to hazards for workers and minimizing the likelihood of accidents caused by distracted drivers.

In the context of traffic control devices, AFADs provide an effective solution for managing vehicle flow through construction areas, ensuring clearer communication of instructions to drivers. This also facilitates smoother transitions through work zones, enabling quicker completion of projects and reducing delays for motorists.

The other options represent different types of devices: RTDS (Roadway Traffic Detection System), PCMS (Portable Changeable Message Sign), and TSA (Traffic Safety Advisory) serve different purposes in traffic management but do not specifically provide automated flagging capabilities like AFADs do.