Monitoring System and Method for Operating the System

A method and monitoring system includes a first person detector that is configured to output a first position indicator relating to a person identified in a monitoring region via a first channel, a second person detector which is configured to output a second position indicator relating to the person identified in the monitoring region via a second channel, and a diagnostic unit having first input for receiving the first position indicator, a second input for receiving the second position indicator, and a first output for a checked position indicator relating to the identified person and a second output for an error signal.