How far apart should repeater speed limit signs be placed after the initial kilometer of a new speed zone?

Repeater speed limit signs serve to remind drivers of the current speed limit as they travel through a new speed zone. After the initial kilometer of a new speed zone, these signs should be placed at regular intervals to ensure that the speed limit is clearly communicated and reinforced.

The recommendation for spacing these repeater signs at one kilometer apart after the initial distance is based on traffic engineering principles that aim to provide adequate visibility and consistent information to drivers. This spacing helps maintain awareness of speed limits, which is crucial for safety, minimizing accidents, and ensuring smooth traffic flow.

In contrast, the other options suggest either too close or too far a spacing that may not be as effective in maintaining driver awareness of the speed limit. For example, closer intervals might lead to sign congestion and reduce the effectiveness of the signage by overwhelming drivers with information, while farther intervals may result in drivers forgetting the speed limit established at the beginning of the zone. Hence, the one kilometer interval strikes a balance between visibility and effective communication of speed regulations.