Key Control Basics

While you can buy locks that require special keys, called 'restricted' keys, that take special documentation or identification to have made, and you can buy special key cabinets in which to store and track keys, key control is not something you can buy. Key control is something you exert.

The key to key control is organization. A good key cabinet can help, but a key system must be managed by a person or persons to be effective. The key system manager must be prepared to chase down a key that has gone astray or change the system so that the errant key is eliminated. The manager of the key system must also be knowledgable enough to know when these actions are necessary and how to help prevent breaches. I hope this article will be helpful in preparing a person to manage a key system.

Think of a master key system as an army of keys. The lowest link on the chain of command is the pass key. Typically this key opens one lock in the system. The next step up would be a submaster key. Submasters open more than one lock within a system, but not all locks. One might assign submaster keys, for example, to floors in a highrise commercial building. Above the submaster is the master key, which opens all the locks within that system. There is a step above master key, called grandmaster key, as well. Typically grandmasters are used where large numbers of locks are involved. For example, a commercial real estate management company might manage a dozen highrise buildings each with its own master key, and they might also have a grandmaster that opens all the locks in all the buildings.

The further up you go in the chain, the greater your vulnerability. For example, if you give a pass key to a repair person and that person steals something and disappears, as key system manager you must have one lock changed. If you gave the repair person a submaster key, you would have to change all the locks that the submaster operates.

There are a finite number of key changes possible within any given key system, limited by the number of cuts, number of possible depths, permissable disparity of adjacent depths, and subtraction of unusable combinations. In addition, whenever a lock is keyed to more than one key, a number of theoretical keys, called incidental keys, could also open that lock if they were created. When these keys are created and used elsewhere in the system, it is said that those locks are cross keyed. Elimination of these incidental keys also limits the number of changes possible within a master key system.

One way lock manufacturers have worked to increase the number of possible changes is to create heirarchical key sections. The key section is the shape of the key that permits its insertion into a lock. Because a key of one section cannot be inserted into a cylinder of another section, changes can be effectively reused within a system, expanding the number of usable changes.

Standard keys raise tumblers inside a lock to a certain level that permits the cylinder to turn, unlocking the lock. Some cylinders incorporate what amounts to an extra set of tumblers that cause the key to perform two simultaneous mechanical processes instead of one. These high security locks have greater resistance to simple entry techniques such as picking and bumping, and sometimes drilling. Usually they also offer restricted keys - that is, keys that are difficult to get duplicated without proper documentation.

Two examples of restricted keys are Medeco and Schlage Primus.

The key system manager's job is to know where, who, why, and when, that is, where a key works, who it is that took the key, why they took the key, and when they took it and when they are supposed to bring it back. One of the most useful tools in handling this information is the key storage cabinet.

If keys will be handed out by an individual, the cabinet should be situated so that anyone who wants the key must ask the individual so that the individual can record the name, date, and time the key was taken. If access to keys will be supervised by an advanced technology key storage device its location is not as critical.

The key cabinet is a great place for key control and access control to collaborate. Personnel can use their prox card or other credential to gain access to keys. The access control system can time-stamp the event when they use their credential to gain access to a closet containing the key cabinet.

If you are managing a key system for a system of 100 locks or less and demand for keys is not constantly high, a simple spiral notebook, divided into columns for name, key number, location, time out and time in should suffice. If you are managing hundreds of locks with high traffic in and out of the key cabinet, you will be better off using a spreadsheet program. If organization is not your strong suit or you find the number of entries in your system daunting, key system managment software is available from several manufacturers. Ask your locksmith or security professional for advice on which program might be best for your needs.

There are traditional numbers used by locksmiths to identify keys within a system. You can use the traditional system or devise your own and give it to the locksmith to apply to your key system.

The most important factor concerning key tracking is that you do it. If you don't do it, you don't have key control; you have key OUT OF CONTROL.

The traditional key numbering system goes more or less like this with variations depending on who you talk to. The system designates the top key, "A". if "A" is a grand master, masters might be designated "AA", "AB", "AC", etc. Submasters under each master would go like this: "AAA", "AAB", etc. Pass keys would have numbers like this: "AAA1", "AAB2", etc. In this system, the key, "AAB3" would be key number 3 under submaster AAB under master AA under grand master A.

What is important about a key numbering system is that it helps the key system manager quickly identify any key within the system.