Final answer:
When placing warning signs for a limited area on or outside the limited area physical barrier, the interval between the signs should be determined based on factors such as the distance from which they can be easily seen and understood by drivers, the speed limit, visibility, and complexity of the limited area.
Step-by-step explanation:
When placing warning signs for a limited area on or outside the limited area physical barrier, the interval between the signs should be determined based on the distance from which the signs can be easily seen and understood by drivers. The purpose of warning signs is to alert drivers to potential hazards or changes in the road conditions ahead. The interval between signs may vary depending on factors such as the speed limit, visibility, and complexity of the limited area. For example, on a highway with a high speed limit, the signs may be placed at larger intervals to give drivers more time to react, while on a city street with lower speed limits, the signs may be placed closer together.