For urban areas with high speeds, what is the recommended spacing for advanced warning signs?

In urban areas with high speeds, the recommended spacing for advanced warning signs is 350 feet. This spacing is crucial because it provides sufficient distance for drivers to react to upcoming changes in traffic conditions, such as road work or other obstacles.

The rationale behind this specific distance is based on the need for adequate reaction time. Drivers must have enough notice to adjust their speed or change their driving behavior, particularly in environments where high speeds are prevalent and traffic conditions may quickly change. A spacing of 350 feet allows drivers to see the sign well in advance, assess the situation, and react accordingly, contributing to enhanced safety for both drivers and workers in the area.

In contrast, shorter distances may not provide enough reaction time, particularly at higher speeds, potentially leading to hazardous situations. It's also critical to consider factors such as visibility, sight distance, and the complexity of the environment when determining appropriate sign spacing. This further underscores the importance of the 350-foot spacing as the standard for advanced warning signs in areas where high speeds are present.