The ARNOLD safety system may be equipped with different kinds of communication units featuring traffic lights as well as acoustical alarms.

Traffic lights inform truck drivers and loading personnel if the loading bay is ready for docking or (un)loading respectively. They are available with one (red or green), two (red and green) or three (red, yellow, green) lights and may be used indoors as well as outdoors.

The ARNOLD safety system also features acoustical alarm devices that are usually integrated into the control boxes.