Which of the following is NOT a function of the stacker horn?

The correct answer reflects that sounding the horn when facing another stacker is not typically a designated function of the stacker horn. The primary purposes of the horn on a stacker are to enhance safety and communication in busy environments.

When reversing, the horn signals to both the operator and the surrounding personnel that the stacker is moving in reverse, which is crucial for avoiding accidents. Additionally, to ensure pedestrians are aware of the stacker’s presence, the horn acts as an alert mechanism, promoting safety in areas where foot traffic may intersect with machinery. Finally, the horn serves to indicate the presence of the stacker in areas where visibility might be limited, adding an extra layer of awareness for both operators and pedestrians.

The focus of the stacker horn is on safety and operational awareness rather than specifically signaling to other stackers, thereby making that choice the appropriate one in the context of functions typically associated with a stacker horn.