What is a critical design requirement for Type 1 barricades?

Type 1 barricades are primarily used for guiding and protecting traffic in work zones. A critical design requirement for these barricades is that they must have one horizontal rail. This design helps provide adequate visibility and ensure that road users can see the barricade from a distance, which is essential for safety in work zones. The specific structure with a single rail allows for straightforward installation and maintenance while still conveying necessary warnings and directing traffic effectively.

In contrast, other types of barricades may have different configurations or materials based on their intended use and the level of protection they offer. The requirement for one rail specifically highlights the minimalist yet effective standard for Type 1 barricades, which are designed for specific applications where full enclosure or multiple rails may not be necessary or practical.