North Carolina Locksmith Practice Exam

What prevents the entry of an incorrect key into a cylinder or lock?

1. Key Blank

2. Key Way Ward

3. Composite Keyway

4. Multiplex Key System

The correct answer is: Key Way Ward

The key way ward is a critical feature in a lock design that serves specifically to prevent the insertion of an incorrect key. This mechanism is achieved through the inclusion of obstructions within the keyway, which aligns with the corresponding cuts and notches of the correct key. When a proper key with the appropriate profile and cuts is inserted, it smoothly travels through the keyway and interacts with the wards, allowing for normal operation of the lock. However, when an incorrect key is introduced, the design of the wards effectively obstructs it from fully entering the cylinder, thus ensuring that only the correct key can operate the lock. In contrast, the other options refer to different concepts in key and lock security. The key blank, for instance, is simply the uncut form of a key, and does not provide any functional security against incorrect key insertion on its own. The composite keyway is a term that can describe a more complicated key way design but does not specifically prevent unauthorized keys from entering. The multiplex key system pertains to a type of locking mechanism that offers enhanced security controls, but it does not directly address the function of preventing incorrect key entry at the foundational level of the lock design like the key way ward does.