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Locks can also be electrified. Mortise or bored locks are available electrified. An often overlooked consideration in specifying electrified locks is that a raceway has to be drilled across the width of the door to accommodate the wires, and an electrified hinge has to be used as well to continue the wire run through the frame. Securing devices can also be electrified and used in conjunction with electrified access control. Electrified locks have voltages that must be considered and they must be specified fail safe or fail secure as well. Fail safe is a term applied to locks that require power to lock and, upon loss of electricity, unlock. The fail secure term indicates a condition that requires power to unlock. One example of the fail secure function is a security institution that must remain secure even if power is lost. Again, knowledge of life safety and fire codes is necessary in choosing mechanical and electrified locks for commercial use.

Securing a door commercially may involve specifying exit devices (or panic devices as they are often referred to). Exit devices were designed for life safety to allow simple exit from a building for many people. Use and application of exit devices will depend on life safety and fire codes. Only exit devices that bear a label indicating that they are approved and tested for use on fire-rated assemblies can be used on fire-rated doors. When to use an exit device and how many are necessary in a building is determined by occupancy use and occupant load. More information on that subject can be found in NFPA Life Safety Code 101.

Controlling the movement of the door

The next section that must be specified is how to control the movement of the door when opening and, if necessary, when closing. All applicable codes should be consulted before specifying which doors need closers. NFPA 80 states fire-rated doors must be self-closing. The use of the door will also determine if it needs a closer. Closers can be concealed or surface mounted. There are four basic applications of surface mounted closers:

• Regular arm mount — applied to the pull side of a door and the closer mounts on the door while the arm is mounted to the frame.
• Parallel arm mount — applied on the push side of doors and while the closer is also mounted on the door, the arm lies parallel to the door rather than protruding as it does in regular arm mount.
• Top jamb mount and the closer body — mounted on the frame and the arm on the door. Aluminum and glass doors use the top jamb mount most often.
• Concealed closers — mounted either in the top jamb of the frame or in the top of the door. There are circumstances where you want to use concealed closers for aesthetic reasons; however, for the majority of commercial applications, surface mounted closers suffice.

Concealed closers are much more expensive and require additional prep work in the door and frame. If specified, it is important to note that enough room must be left at the top of the door to accommodate the closer whether the door is hollow metal or wood. The top horizontal section of a wood door is called the top rail. If windows or panels are to be used in the door, the top rail has to have sufficient room for a closer. Also, the doors require reinforcing to accommodate the closers if thru-bolts are not used. Wood doors need blocking as reinforcement.

 

Architectural pull. Courtesy Trimco.

So, when specifying closer application, door material and design should be important factors influencing the choices. It is also important to know where the closers will be mounted and make sure all preferences are specified. For aesthetic reasons, closers are mounted on the room side in corridors to maintain a clean look. In stairwells, they should be mounted in the stairwell to keep them out of sight.