Master Key Systems and Keying Flashcards

What is a 'sectional' or 'patented' keyway, and how does it support key control?

Answer: A keyway protected by patent law so that key blanks cannot be legally duplicated without authorization, limiting who can copy keys

Patented/restricted keyways have legal protections preventing unauthorized key blank duplication, ensuring only authorized dealers can cut new keys.

In a master key system, what is a 'cross-keying' problem?

Answer: When two or more change keys in the same system can operate each other's locks, which is an unintended security flaw

Cross-keying occurs when the combination of master wafers and change key bitting accidentally creates a shear line that allows an unintended change key to open a different lock in the system.

What does 'keying alike' mean?

Answer: Multiple locks are configured to operate with the same key

Keying alike (KA) means two or more locks are set to the same key bitting so a single key can operate all of them, regardless of whether a master key system is in place.

What is a 'key bitting specification' sheet used for by locksmiths building a master key system?

Answer: To record the cut depths assigned to each key in the system, ensuring correct combinations are maintained and cross-keying is avoided

A key bitting specification sheet records each key's cut depths, allowing the locksmith to track all combinations in use and mathematically verify there are no cross-keying conflicts.

What is the function of a 'construction master key' (CMK) in new building projects?

Answer: A temporary master key used during construction that is rendered inoperative when the building owner's permanent keys are first used

A construction master key allows construction workers access during building but is designed to be disabled (made inoperative) when the permanent change keys or owner's master keys are first inserted.

What is a 'great grand master key' (GGMK) in a multi-level keying hierarchy?

Answer: A key that operates all locks in the system and sits above the grand master key level, typically used for a campus or multi-building complex

A great grand master key (GGMK) is a hierarchy level above the grand master key, used in large systems (e.g., university campuses) to provide access to multiple buildings each with their own GMK.