What do the yellow lines on an automotive shop floor indicate?

The yellow lines on an automotive shop floor serve as a visual cue for caution. This coloring is universally recognized in various industrial and workshop environments, signaling to personnel that they should be alert and watchful while moving through that area. Yellow typically indicates areas where potential hazards may exist, such as zones that could be slippery, sections where equipment is frequently in operation, or pathways where workers and vehicles may be in close proximity. Understanding the purpose of these yellow markings is crucial for maintaining safety in the shop, as they help to prevent accidents and injuries.

In the context of the other options, "Do not enter" would typically be marked with a red line or sign, while "No PPE required" would not be indicated with a specific floor marking. The water supply would usually have blue markings to signify its presence, further differentiating it from cautionary signs.