What is an example of a device that should never be used on its own in a work zone?

Traffic cones are an essential component of work zone traffic control; however, they are designed primarily to guide and inform drivers and do not provide physical protection or a clear warning by themselves. Utilizing traffic cones alone can lead to confusion for drivers, as they may not adequately convey the necessary message about detours, hazards, or the presence of workers. In a busy work zone, their effectiveness can be limited without additional control measures to enhance visibility and safety.

For optimal safety, it is recommended to use traffic cones in conjunction with other traffic control devices, such as warning signs, flaggers, or construction barriers. These elements work together to effectively communicate the work zone's status and the necessary precautions drivers should take when navigating through or around the area. By having a multi-layered approach to traffic control, the risks associated with work zones can be significantly reduced.