What is essential for the visibility of flaggers at night?

Reflective materials on clothing are crucial for ensuring that flaggers remain visible at night. The use of reflective materials enhances visibility by reflecting light from vehicle headlights and other light sources, which is vital in low-light conditions. This characteristic allows flaggers to be seen from a distance, thus improving their safety as they direct traffic through work zones.

While other options may contribute to overall safety in a work zone, they do not specifically address the visibility of the flagger in the same way. A flashlight, for example, could help illuminate the area but does not provide a means of being visible to oncoming traffic. High-visibility safety cones and brightly colored barriers can aid in directing vehicles, but they do not enhance the visibility of the flagger themselves. Therefore, the use of reflective materials on flaggers’ clothing is the most effective method for ensuring that they are seen and safe while performing their duties at night.