KEYING SYSTEMS AND NOMENCLATURE Keying Procedures, Systems, and and the authors of the previous FOREWORD Nomenclature was first published in editions should take pride in the 1965, revised in 1969, 1975 and again results. in 1978. It introduced a procedural There are still some misapplications system of keying terminology radically and misunderstandings of the system different from that commonly used and it is the purpose of this edition to prior to 1965. The need for standard clarify the system to avoid terminology was clear but the misunderstanding. With this in mind, acceptance of the new system was text and format changes have been slow. made with the aim of introducing Manufacturers, Distributors, Building criteria in their order of complexity, to Owners, and Operators were make the manual an even better frustrated over the use of various and instructional tool for those progressing differing terms. Among those using the through basic, intermediate, and terms, different meanings and advanced study of the subject. interpretations were applied. As a Since the manual does not cover result, errors were made, and frequent actual keying procedures, the title of correspondence occurred between the manual has been changed. For manufacturers and distributors, those interested in the actual seeking clarification. The consumer techniques of keying or the sometimes had a sketchy mathematics of setting up a key understanding of the key system he system, many fine books and had purchased. publications are offered by the lock- Since its inception, the procedures smithing industry. outlined in this manual have been taught at the DHI Technical Programs Robert Perry, AHC/CDC John R. and the results have been gratifying. "Jake" Dalbert. AHC Richard The use and understanding of the Hudnut, DAHC system is now close to industry wide, Copyright 1989 by the Door and Hardware Institute First Printing 1965 Revised 1969, 1975, 1978 Reprinted April 1999 INDEX page: FOREWORD .................................................................................................................. 1 INDEX ............................................................................................................................ 2 CHAPTER 1 Planning a Key System ..................................................................... 3 Basic Facts of Key Systems Steps to Structure a Key System CHAPTER 2 System Theory .................................................................................. 5 Basic Levels of Keying Key and Cylinder Coding System CHAPTER 3 Level One System ............................................................................. 7 No Master Key CHAPTER 4 Level Two System ............................................................................. 8 Single Master Key System Exceptions: Omitting the master key Cross keying CHAPTER 5 Level Three System ......................................................................... 10 Grand Master Key System Exceptions: Omitting one or more levels Cross keying More than 23 master keys Leading Zero's CHAPTER 6 Level Four System ........................................................................... 11 Great Grand Master Key System Exceptions: Omitting one or more levels Cross keying CHAPTER 7 School Key System Guidelines ........................................................ 12 CHAPTER 8 Hospital Key System Guidelines ...................................................... 14 CHAPTER 9 Hotel Key System Guidelines .......................................................... 15 CHAPTER 10 Office Building Key System Guidelines ........................................... 17 CHAPTER 11 Multiplex Key Systems .................................................................... 18 CHAPTER 12 Key Control Systems ....................................................................... 19 Planning a Key Control System Tips for Setting Up Systems Lock and Key Survey CHAPTER 13 Maintenance of Key Systems .......................................................... 21 CHAPTER 14 The Key Conference ........................................................................ 22 Setting up the Conference Preparing for the Conference During the Conference The Work Sheet CHAPTER 15 Key System Limitations ................................................................... 25 Key Depths Mathematical Limitations Multiples of 4 CHAPTER 16 Recommended Standard Definitions ............................................... 27 CHAPTER 1 The keys in a keying system relate to Prepare a Schematic Diagram of the each other and to the system as a Proposal PLANNING A KEY SYSTEM whole. This relationship restricts keying options and the flexibility of the Suggest an appropriate keying system, "Hardware consultants render one of system design. based on building function. their most useful services by designing Bring the study into focus and begin a practical and efficient keying system Keep It Simple to diagram a concept of how the for a facility. The more complicated the design of keying system will work. Like many Because the principles of keying are the keying system, the shorter its things, real success comes in being not understood by those outside the usable life. Key a building to perform able to simplify what would appear to field of locks, a consultant's services its function. Do not key it to individuals be a complex system. It takes very are most valuable in guiding the on an organization chart. Personnel/ little talent to make complex keying organization of keying so it will: People relationships and organizations schedules. 1. Function properly change rapidly. Building functions Diagram the schedule, and look for 2. Be easy to understand survive for many years. An intricate every opportunity to use the same 3. Be practical enough to survive system, misunderstood by the owner, change key on as many doors as years of usage usually degenerates quickly. The result possible. Where doors have similar 4. Provide the security is usually that everyone ends up with a purpose and will be used by similar required by the user master key. type people, key them alike. As a first rule, use the lowest level of BASIC FACTS OF KEY SYSTEMS Break Up Very Large Systems keying possible until the system forces you into a higher level. There will be The following basic facts apply It is unwise to tie too much together many doors where logic tells you no regardless of the manufacturer, type of under one "top" master key. If the "top" change key will be used. In situations cylinder, or key involved in the system: key is compromised (loss, theft, like this, it is appropriate to masterkey duplication, decoding), the entire (no change keys) only. Security Is Inversely Proportional to system must be rekeyed. Remember the limited availability of Convenience different change keys and use them STEPS TO STRUCTURE A KEY sparingly. The owner will thank you in A cylinder operated by a single key is SYSTEM years to come as this will leave most secure. Each additional key flexibility in the system. Minor additions operating the same cylinder increases Research the Building Function and modifications can be made under the number of shear lines. This these conditions without redoing the reduces the security of the cylinder by How, when, and by whom will it be entire system. making it easier to pick or be opened used? Buildings are designed to serve Don't start out with a preconceived by unauthorized keys. a function. Study the function of the notion over the necessity of a great building, the flow of traffic, the purpose grand or grand masterkey. Build from Durability Is Affected by the Level of of various areas. Design the keying the bottom up and let requirements Keying system to accomplish these purposes. dictate where it is appropriate to Try to visualize the category of people establish higher key levels. Key the A cylinder operated by a single key by their function, the areas they must building and not the people. lasts longest. Each additional key reach to perform their duties and the Do not be concerned if some people operating the same cylinder requires different times in a working day when have to carry two or more keys. This is •more master pins of different these perform specific duties. Try to for more preferable than having a increments. The number of master imagine where they must move, when system where a key operates cylinders pins increase with each successive and how. Remember also that a under different masterkeys. If level of keying. This causes greater proper keying system is based on the uncontrolled crosskeying is permitted, wear and increases the chances of building function, not personnel. it rapidly eliminates available change malfunction of the cylinder. In most structures there are relative keys which must be discarded and not degrees of security to be considered in used in the system. Intricate systems There are Limitations setting up the keying. Again, using a can be made secure but more often hospital illustration, narcotics lock-up than not, prove to be unnecessary and There are a limited number of change, and operating room facilities carry a difficult to maintain. master, and grand master keys that high security classification. Security is can be established within a keying partially achieved by greatly limiting Present the Proposal. system. This limitation is physical and the number of keys to an area and in mathematical in nature and exists some cases, limiting operation of a (See Chapter 14 for additional within all systems.