Terminology Tuesday: Access Control Terms


I’ve gotten a lot of great feedback on the posts I’ve published that define terms, so this week I thought I would tackle Access Control. I figured I would simply discuss “egress” and “biometric readers” and “proximity cards” and then make a cute comment or two on the terms used like “Tailgating”. Everyone knows tailgating is what you do before a football game or NASCAR race – but in the Access Control world, tailgating refers to someone “following” an authorized person into a secure area. 

As with anything I write – I do a little fact checking to see that I am covering my topic adequately, and to my surprise – I wasn’t going to be close. There is a lot of terminology in the access control world. So, I have decided to give a very short synopsis of terms here – and then I created a useful PDF attachment with a more significant list of useful terms. 340 terms to be exact, so when you get to the bottom of this short list, be sure to check out the download. 

Here is the “short list” of terms (67) I put together: 

  • Access Control: Any system or method which automatically controls the passage of people and vehicles into or out of an area or structure.
  • Actuator: A manually operated or automatically controlled switch or sensor which initiates a signal that can be processed by an access control system.
  • Alarm Annunciation: The act of announcing that an alarm event has occurred. Annunciation can be done by an audible alarm, warning lamp or LED, or a pop-up window or message (in the case of alarm monitoring via computer software).
  •  Access Relay: An electrically operated switch that is activated when access is granted to unlock a door.
  • Anti-Passback (APB; Anti-Tailgating): A feature that will not allow any card to re-enter unless it has been used to exit. This requires that readers be used for both entry and exit.
  • Badge: An identification card usually displaying a cardholder’s photo, signature or other specific identifying characteristics.
  • Barium Ferrite Card: An access control card with identification information encoded in the card via magnetic material embedded in the card.
  • Biometrics: A machine readable technology that allows for the identification of individuals by reading unique biological features (i.e. fingerprints, hand geometry, voice analysis, the retinal pattern in the eye).
  • Cam: A rotating eccentric piece attached to the end of a cylinder plug to actuate a lock or latch mechanism. 
  • Card Reader: A device that retrieves information stored on an access card and transmits that information to a controller.
  • Coercivity: The property of a magnetic material, as on magnetic stripe keys, which is a measure of the coercive force. 
  • Controller: A microprocessor based circuit board that manages access to a secure area.
  • Deadlatch: A latch in which the latchbolt is positively held in the projected position by an auxiliary mechanism.
  • Distributed Intelligent Devices: Access control devices that make their own access decisions uploading event messages periodically to the central processing unit for storage.
  • Door: A generic term for a securable entry way. In many access control applications a “door” may actually be a gate, turnstile, elevator door, or similar device.
  • Door status switch: A DSS is a switch used to monitor whether a door is in an opened or closed position
  • Duress Alarm: A device that generates a silent alarm signal in the event a person is experiencing Duress. This device may be a standalone signaling device or it may be incorporated into a reader.
  • Egress: Passage through an opening in the exit direction, especially passage that leads out of a structure (opposite of ingress).
  • Easy egress: A means of exiting where the person wishing to leave simply turns the doorknob to exit.
  • Electric Strike: A door unlocking device that is installed in the door jamb and that works in conjunction with a mechanical lock or latch mechanism. Requires power to be applied to unlock a door.
  • Embossed Card: An access control card that uses a raised pattern as a means of encoding data.
  • Event: An occurrence at a controller (such as unlocking a door, requesting to exit, forcing a door open) that generates a message stored by the controller.
  • Exit Alarm: A device that indicates (either audibly or silently) that a secure door has been forced opened.
  • Exit Lock: A push-bar door lock that spans the width of the door, used for emergency exit. An Exit Lock may be connected to an Exit Alarm.
  • Fail-Secure: An electric lock that requires power to unlock. Also called fail-locked.
  • Fingerprint Reader: A biometric reader that identifies a person based on the person’s fingerprint pattern.
  • Global Linking: An input at one Access Control panel affecting the output at another.
  • Hand Geometry: A biometric access control technology that verifies a person’s identity by using the variations in hand size, finger length, and finger thickness.
  •  Identification Card: A card that stores the information necessary to verify the identity of the cardholder.
  •  Infrared Light: Light with a wavelength that is too low to be seen by the human eye.
  •  Input: An electronic sensor on a controller that detects a change of state in a device outside the controller. See Normally-Closed, Normally-Open
  •  Interlock: A system of multiple doors with controlled interaction.
  •  Intermittent duty solenoid: A solenoid designed to be energized for short periods of time.
  •  Key Tag: An access control identification device assigned to an individual to give that individual access rights to an access control system.
  •  Keypad: An alphanumeric grid which allows a user to enter an identification code.
  •  Keyless Access Control: An access control system that controls access using something other than a key and a lock; typically some kind of reader and an electric door lock.
  •  Latching Relay: A relay that when set (either ON or OFF depending upon the relay configuration), locks into place until reset either manually or by a signal.
  • Line Drop: The drop in voltage along a power line caused by the resistance, reactance, and/or leakage in the line’s wires.
  • Local alarm: A visual or audible signaling device located at a monitored door, window or other opening.
  • Magnetic Lock: A door lock made up of an electromagnet and a strike plate.
  • Magnetic Stripe Reader: A reader capable of reading and interpreting cards using magnetic stripes to encode data.
  • Maintained contact switch: A switch designed for applications requiring sustained contacts but with provision for resting. 
  • Masking: Hiding or suppressing alarms that the operator does not wish to be viewed.
  • Master Code Card: An access control card that grants access and exit at every card reader on the system.
  • Passive Infrared (PIR) Detector: A motion sensing device, often used for intrusion detection systems
  • Piggybacking: 1) More than one individual entering a secure area using one access card. 2) Following an authorized person into a secure area.
  • Proximity: A non-contact system for reading cards. Data is exchanged between card and reader by radio frequency, fiber optics, induction, laser or other non-mechanical contact technology.
  • Proximity Reader: A reader capable of reading and interpreting cards using radio frequency identification to encode data.
  • Push-Button Lock: A locks that opens when a set of push-buttons are pressed in sequence or in unison.
  • Reader: A device that can read the encoding on a card or badge.
  • Request to Exit (RTE): A signal that informs the controller that someone has requested to exit from a secure area.
  • Remote reset: A switch located at a monitored opening. If a violation occurs, the alarm at the control console can not be turned off
  • SSP (also SSP-C, and SSP-E): Synonymous with panel and controller.
  • Secure Area: A designated area in which access into and out of is controlled and can be monitored.
  • Security Condition Sensor (scs): A sensitive crystal relay to operate the LED with an SPOT switch indicate low voltage and tampering of the lock locally or to a remote monitoring location.
  • Security interlock: A multi-door system in which doors are normally closed and locked; releasing doors disables the releases for release for all other doors until the first door is closed and relocked
  • Shunt: Electrical term for bypassing. In access control it is common to shunt an alarm sensor, such as a door position switch, when a door is about to be opened for valid access or egress.
  • Shunt Time: The time in seconds that a door-open alarm is suppressed after the door has been opened.
  • Signature Verification: A biometric identification method using a person’s signature characteristics (writing speed, pen pressure, shape of loops, etc.) to identify that person.
  • Smart Card: A plastic card with an embedded microchip, which can be used to store information about the cardholder or record card transactions as they occur.
  • Solenoid: An electro-mechanical device that operates the lockbolt. When electricity is applied, a mechanical motion is obtained that moves the bolt.
  • Spike: A voltage peak of high amplitude and short duration. See Transients.
  • Springlatch: A plain latch switch, a beveled latchbolt that is activated by springs.
  • Strike: A plate mortised into or mounted on the door jamb to accept and restrain a bolt when the door is closed.
  • Tailgating: 1) More than one individual entering a secure area using one access card.
  • Transients: Electrical surges or spikes conducted through power or data lines.
  • Wiegand Effect: Electrical pulses generated when individual sections of specially processed magnetic wire is passed by a pickup coil. Each section of this magnetic wire has its own magnetic field. Depending upon the strength of the individual magnetic fields, the pickup coil either senses a strong field or overpowers a weak field, which generates an electrical pulse. 

Download a more complete list now (340 terms!) Did I miss any important terms? Let us know in the comments below:

6 Responses to Terminology Tuesday: Access Control Terms

  1. Frank Bisbee said on
    October 11, 2011 at 12:20 pm

    Harry Newton’s famous NEWTON”S TELECOM DICTIONARY could certainly benefit from CSC’s Terminology Tuesdays. Well done.
    Keep up the grfeat support for your customers.
    Frank Bisbee – HOTS – Heard On The Street monthly column

    • Stefanie Rembiszewski said on
      October 11, 2011 at 12:56 pm

      Thanks Frank, it is great to see another major contributor to our industry’s news reading and sharing our blog.

  2. William A. Boyd said on
    October 12, 2011 at 8:03 am


    Thanks for posting these and maintaining the blog entries. They are useful, and at times entertaining.

    • Stefanie Rembiszewski said on
      October 12, 2011 at 10:26 am

      Thanks William, I am glad you are enjoying my articles, my goal is to always give you useful info, but I do try to make some of the technical stuff more interesting – and more “relatable to everyday life”.

  3. Emmanuel Odongo said on
    January 9, 2015 at 6:27 am

    Hi, this has really helped me. I am writing up a RFP for Access control system. This is good work

    • Stefanie Rembiszewski said on
      January 9, 2015 at 11:51 am

      I am so glad that you found this useful. I am sure your local WESCO Communications and Security (AKA CSC) representative will be glad to assist you if you have any needs as you develop your RFP. Have a great day!

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