A change key is a specific type of key used in lock systems, primarily in master key systems, designed for operating one particular lock or a set of locks that are keyed alike. This distinct key enables individual access to designated areas while maintaining a hierarchical access control system that also includes master keys and sometimes grand master keys. The use of change keys is common in commercial and institutional environments where different levels of access are necessary.
In a master key system, a change key's role is to interact uniquely with the lock's pin tumbler mechanism, which is configured to match the cuts and grooves on the change key. This specificity prevents the change key from operating other locks in the system that are not similarly keyed. The design and implementation of such systems require precision in key cutting and lock configuration to maintain security integrity and functionality.
The security provided by change keys can be enhanced by employing patented key designs, which restrict unauthorised duplication. The strategic use of change keys can significantly optimise access control, allowing for efficient management of entry permissions without compromising the security of the overall environment.