A graduated scale of protection ensures that security can be cost effective. Highly public sites demand consideration of traffic patterns and vehicle control. As the recent bombing of the Khobar Towers in Saudi Arabia demonstrated, vehicles need not be close to a building to be a threat. Access Control Controlling access to buildings is equally important. An electronic access control system can obviate the need to post guards at every door and can save money.
Access control can also add flexibility to facilities.
For example, a school district recently installed card readers in all its schools and issued access cards to faculty, staff, and some members of community groups. The system, controlled by IDenticard Systems' Series 9000 software, allows members of a community volleyball league to enter the school and its gymnasium on certain days during certain periods but does not permit access to other parts of the building. Access control is not limited, however, to identification cards or access badges. Keypads which accept personal identification numbers decrease the likelihood that a lost or stolen card can be used. Alarm monitoring is a common component of access control systems.