Dortronics Systems Inc. has introduced its 4700 Series mantraps. Offering secure interlock door control, the mantraps provide an economical solution for small systems security. Suitable for air locks or security mantraps, with up to four normally unlocked doors or three normally locked doors, the unit can be programmed at the factory to allow for only one door, in any defined area, to be unsecured at a time. A request for access at any normally locked door will inhibit the REX inputs for all other locked doors and secure all unlocked doors in the area. Simultaneous requests for access or requests for access while another door is unsecured are denied to maintain the highest level of control. The controller may also be customized to control automatic door openers and provide timing and logic sequences for biological wash-down controls.