Airport terminals have large volumes of people moving through. You can use the multiple sensor capability of WinCounter to monitor people movement in different areas of the terminal.
Anywhere you can mount a sensor, WinCounter will count people. Monitor people as they enter and leave gates, cafe's baggage areas, etc. etc.
By mounting two sensors in the appropriate configuration, WinCounter can be configured to determine the direction of the people moving through various parts of your terminal.
If you have directional sensors then you can have WinCounter display an on-screen total which show the occupancy of the terminal or any area at any time. This is based on the difference between incoming and outgoing sensors.