In a mantrap there are two doors which are on the opposite sides in a room. The doors are designed such that any door can be opened only when the other door has been locked and closed.
One door of a mantrap cannot be unlocked and opened until the opposite door has been closed and locked. Mantraps are used for separating secure areas from non-secure areas and prevention of unsanctioned access. They are used in semiconductor manufacturing industry as exit and entry chambers in clean rooms. The two interlocking doors which are used in mantraps are interfaced in such a way that when one of them is unlocked the other one locks automatically. Only authorized persons who possess valid authentications like key fobs,biometrics or smart cards can enter mantraps. There are certain mantrap systems which use thermal imaging or 3D optical imaging for preventing access by more than single individual at a particular time more than one person from passing through a mantrap at the same time( Rouse,2011).
In fail-safe configuration, the mechanisms fail and the systems,personnel experience minimum harm. In fail-secure configuration,the mechanisms fail in a restrained manner and access is blocked. Here the system is present in a unpredictable state. During power failure in a data center when the mechanisms associated with door systems are operated in fail safe configuration,all the employees can safely exit from the data center. If the mechanisms associated with door systems are operated in fail-secure configuration,the employees are in danger since the doors are locked and they cannot exit from the data center. Both fail-secure and fail-safe configurations are regularly tested for ensuring that they operate as per design specifications. In an incident of fire,the doors of data center will open to let all the employees escape. This illustrates fail-safe operation.
Electric-lock doors and electric strike doors are configured for operation in fail-secure or fail-safe modes. In electric-strike doors the strike retracts while the the bolt is stationary. In fail-safe mode,the strike is de-energized and it retracts. The door can be opened from the safe side. In fail-secure mode of operation, the strike stays in its original position and manual key is required to unlock the closed door from the safe side. Magnetic lock is easily back-fitted to the existing door systems. They are surface-mounted onto the door frame. Continuous application of electric power to the magnets keeps the door closed. They can be operated in fail-safe mode. They have a serious disadvantage with respect to security.
According to regulatory requirements,the magnetic lock doors must have a manual override button,automatic sensor or request to exit (REX) mechanism for overriding the door lock in an emergency. A card reader controls the locks and when it is activated the protected door is opened to permit entry. These additional devices increase the safety of building. They are also a security risk since they can allow the door lock to be compromised. In a particular situation, the REX mechanism switches off the alarm when a person departs and the locking mechanism is also deactivated by it. An adversary can cause the REX mechanism to free the magnetic lock through various actions(Maiti,Baksi, Zamider,Gorai, &Kisku,2011).
References
Maiti, C., Baksi, D., Zamider, I., Gorai, P., & Kisku, D. R. (2011). Data Hiding in Images Using Some Efficient Steganography Techniques. 260, 195-203. doi:10.1007/978-3-642-27183-0_21
Rouse,M. (2011, October). mantrap (interlocking door controller) . Retrieved January 24, 2017, from http://whatis.techtarget.com/definition/mantrap-interlocking-door-controller