What is the minimum cone height required on an open high?

The minimum cone height for an open high is established to ensure adequate visibility and to provide necessary warnings to both pedestrians and vehicles. A height of 28 inches strikes a balance between being easily visible without being excessively tall, which could create issues in certain situations, such as in low-clearance areas or obstructing sight lines.

In practice, this height is often set based on guidelines that prioritize safety and effectiveness in alerting individuals to potential hazards. Therefore, a cone height of 28 inches is deemed sufficient to convey a warning effectively while remaining practical for varied use cases.