What is the required minimum height for traffic cones used for daytime traffic control?

The minimum height requirement for traffic cones used for daytime traffic control is set at 28 inches for visibility purposes, which is why the correct answer is 30 inches. Traffic cones of this height are more easily seen by drivers, enhancing safety by providing clear visual warnings of road work or hazards. They are designed to be highly visible, particularly in daylight conditions, helping to direct traffic effectively and prevent accidents.

Using shorter cones may not provide sufficient visibility, especially from a distance or when approaching intersections. Therefore, adhering to the specified minimum height is crucial in ensuring that the cones are effective in performing their traffic control function.