For company GDPR and accuracy reasons, it is necessary that the staff at your booth is not included in the Event-Metrics numbers.
For this reason smartphones and other WIFi capable devices that remain in the booth radius for at least 4 hours are blacklisted. This means these devices are excluded from the numbers.
Blacklisting of the device goes for the entire duration of the event, so if a blacklisted device returns the next day and stays for less than 4 hours, it is still not included. It will however be counted again at the next event.