Fastlane Door Detective is designed to increase the level of security at any door that uses access control. The Door Detective creates an infra-red field across a doorway to monitor the passage of every individual passing through the door, only alerting the security staff to the presence of unauthorised entrants. Door Detective helps the access control system overcome the age old problem of controlling how many people pass through a doorway, and in which direction, once a valid access card has been presented and the door is open.