Access control is the mechanism that is used for controlling, restricting and monitoring the movement of assets, vehicles and people in or out any building. A drop arm boom barrier is commonly used for controlling the unauthorized entries of any personnel while enforcing access control system. It assures that one token one-person policy is followed 24 x 7. The levels of security that a boom barrier offers depends on style and type of products being used. For example, if the boom barrier is used with a lockable sliding gate, then it is easier to keep a check on each and every person or vehicle entering. You should know that these are not meant to be used as a pedestrian passage, as a boom barrier is a horizontal bar that is positioned on a pivot that moves up and down.