server is kept. The last thing you need is for someone to spill a bottle of bleach on a $10,000 machine. Computers oſten need to be kept cold and supplied with power 24/7. Master keying the door to the server room makes it too easy for someone to unplug the server (because they need the outlet for a vacuum cleaner), or acciden- tally leave the door open, letting out all the cold air. Single key this lock, even if the rest of the building is master keyed. Only the IT crew needs to carry this key. The same goes for rooms that contain Figure 6. Areas with dangerous machines or chemicals or those with high voltage should have single keyed locks to prevent unneeded access. usually not available on less expensive (or residential-grade) electronic locks. The more expensive locks (which usually have an audit trail) are available with or without a key override. You specify which one you want when you order the lock. But think about what happens when you master key the override cylinder. Suppose this is on a storeroom door. If some stock items are missing, we can con- sult the audit trail. It tells us which codes were used recently. But it gives us no in- formation whatsoever about who might have used a key to bypass the lock. Who has keys that will operate this cylinder? If it’s master keyed, who has access to the master key? This defeats the whole pur- pose of the audit trail! If the customer is serious about us- ing the audit trail, the mechanical over- ride key should be for emergencies only, and the customer should severely limit who has access to the key. Single key the lock so the master key won’t operate here. We’ll assign this cylinder its own special key. We won’t give it an ordinary label like 24AA. We’ll give it a special label, SKD1, which indicates it’s single keyed. 38 KEYNOTES MARCH 2021 Unlike NMK, this is a situation where this particular key never works with the top master key. That’s why they don’t have ordinary key symbols. If you had several of these, the first would be SKD1, the sec- ond SKD2, etc. Because these keys never work with the master, they could be on an entirely different keyway. For example, if most of the building is Schlage, you might use Sargent for the SKD locks. This helps prevent internal key interchange. Clearly, that wouldn’t work if you wanted the key to work with the master in some places but not others. If your SKD keys have a different keyway, you can just use random keys for those locks (but still record them on the bitting list). Alternatively, if you choose to use the same keyway for the SKD locks as the rest of the master key system, be sure to pick the bittings for the SKD locks from the bitting list and mark them as in use, just like you would any other change key. Maintenance and IT Just like the cleaning crew doesn’t need to be in your closet, they don’t need to be in the room where the company’s computer dangerous machines or chemicals, or those that are high voltage (Figure 6). Allowing the cleaning crew or others to access these areas creates unnecessary li- ability. Just like the computer sever room, single key this lock and give the key to only the people who actually need it. Keep in mind that this doesn’t mean all such doors must be keyed different. You might have three janitor’s closets, all of which use the same SKD3 key, and two mechanical rooms, both of which use the same SKD4 key. These locks are single keyed and they are in keyed-alike groups. A System With No Documentation Suppose you get a call at 4 p.m. on a Fri- day aſternoon from the manager of an insurance agency. They just fired one of their employees and want that person’s office door rekeyed right away. You arrive at 4:30 p.m., disassemble the lock cylinder and discover that it has master pins in it. You talk to the manager, who replies, “Yes, the building is master keyed. I have the master right here. Oh, by the way, I want the new office key to still work with my master key.” This would be the per- fect time to consult the bitting list, which shows the bittings of all the keys in the system. Look at keys that are in use, keys used in the past and (most importantly) keys that are available for future use. WWW.ALOA.ORG
