--- title: DGA Blog | Business Security and Fire Systems | Access Control (2) description: Access Control | Our business security and fire systems experts answer the most frequently asked questions, no holds barred. Read on. (2) --- [![cropped-DGA-Security-Logo-nsr-1-1](https://blog.dga.com/hubfs/Assets/logo/cropped-DGA-Security-Logo-nsr-1-1.png)](https://www.dga.com/) Search For: - [Contact](https://www.dga.com/contact/) - [Login](https://connect.dga.com/) - [Careers](https://www.dga.com/careers/) [Get A Free Consultation](https://www.dga.com/free-consultation/) - [Business Security](https://www.dga.com/business-security/) - [Intrusion Alarms](https://www.dga.com/business-security/intrusion-alarms/) - [Video Surveillance](https://www.dga.com/business-security/video-surveillance/) - [Access Control](https://www.dga.com/business-security/access-control/) - [Security System Monitoring](https://www.dga.com/business-security/alarm-monitoring/) - [Environmental Monitoring](https://www.dga.com/business-security/environmental-monitoring/) - [Elevator Emergency Communication](https://www.dga.com/business-security/elevator-emergency-communication/) - [Fire Systems](https://www.dga.com/fire-systems/) - [Design and Installation](https://www.dga.com/fire-systems/design-installation/) - [Testing and Inspection](https://www.dga.com/fire-systems/testing-and-inspection/) - [Fire Alarm System Monitoring](https://www.dga.com/fire-systems/alarm-monitoring/) - [Contractor Support](https://www.dga.com/fire-systems/contractor-support/) - [Industries](https://www.dga.com/industries/) - [Art Galleries](https://www.dga.com/industries/art-gallery-security/) - [Banking and Financial](https://www.dga.com/industries/bank-security/) - [Cannabis](https://www.dga.com/industries/cannabis-security/) - [Hotels](https://www.dga.com/industries/hotel-security/) - [Jewelry](https://www.dga.com/industries/jewelry-security/) - [Nonprofits](https://www.dga.com/industries/nonprofit-security/) - [Offices](https://www.dga.com/industries/office-security/) - [Property Management](https://www.dga.com/industries/property-security/) - [Religious Institutions](https://www.dga.com/industries/religious-institution-security/) - [Restaurants](https://www.dga.com/industries/restaurant-security/) - [Retail](https://www.dga.com/industries/retail-security/) - [Tools](https://www.dga.com/tools) - [DGA Blog](https://blog.dga.com) Search For: [Business Security](https://www.dga.com/business-security/) Business Security [Intrusion Alarms](https://www.dga.com/business-security/intrusion-alarms/) [Video Surveillance](https://www.dga.com/business-security/video-surveillance/) [Access Control](https://www.dga.com/business-security/access-control/) [Security System Monitoring](https://www.dga.com/business-security/alarm-monitoring/) [Environmental Monitoring](https://www.dga.com/business-security/environmental-monitoring/) [Elevator Emergency Communication](https://www.dga.com/business-security/elevator-emergency-communication/) [Fire Systems](https://www.dga.com/fire-systems/) Fire Systems [Design and Installation](https://www.dga.com/fire-systems/design-installation/) [Testing and Inspection](https://www.dga.com/fire-systems/testing-and-inspection/) [Fire Alarm System Monitoring](https://www.dga.com/fire-systems/alarm-monitoring/) [Contractor Support](https://www.dga.com/fire-systems/contractor-support/) [Industries](https://www.dga.com/industries/) Industries [Art Galleries](https://www.dga.com/industries/art-gallery-security/) [Banking and Financial](https://www.dga.com/industries/bank-security/) [Cannabis](https://www.dga.com/industries/cannabis-security/) [Hotels](https://www.dga.com/industries/hotel-security/) [Jewelry](https://www.dga.com/industries/jewelry-security/) [Nonprofits](https://www.dga.com/industries/nonprofit-security/) [Offices](https://www.dga.com/industries/office-security/) [Property Management](https://www.dga.com/industries/property-security/) [Religious Institutions](https://www.dga.com/industries/religious-institution-security/) [Restaurants](https://www.dga.com/industries/restaurant-security/) [Retail](https://www.dga.com/industries/retail-security/) [Tools](https://www.dga.com/tools) [DGA Blog](https://blog.dga.com) [Contact](https://www.dga.com/contact/) [Login](https://connect.dga.com/) [Careers](https://www.dga.com/careers/) Get A Free Consultation - Categories [Subscribe](https://info.dga.com/blog-subscriptions) - [Access Control](https://blog.dga.com/tag/access-control) - [Fire Systems](https://blog.dga.com/tag/fire-systems) - [Intrusion Alarms](https://blog.dga.com/tag/intrusion-alarms) - [Video Surveillance](https://blog.dga.com/tag/video-surveillance) - [Security Terms](https://blog.dga.com/tag/security-terms) DGA Security Blog Our business security and fire systems experts answer the most frequently asked questions, no holds barred. Read on. [Subscribe](https://info.dga.com/blog-subscriptions) - Categories - [Access Control](https://blog.dga.com/tag/access-control) - [Fire Systems](https://blog.dga.com/tag/fire-systems) - [Intrusion Alarms](https://blog.dga.com/tag/intrusion-alarms) - [Video Surveillance](https://blog.dga.com/tag/video-surveillance) - [Security Terms](https://blog.dga.com/tag/security-terms) - [Subscribe](https://info.dga.com/blog-subscriptions) [![Blog Feature](https://cdn2.hubspot.net/hubfs/298890/blog-files/blog--cards-feature.png)](https://blog.dga.com/what-is-electric-strike) [Access Control](https://blog.dga.com/topic/access-control) | [Security Terms](https://blog.dga.com/topic/security-terms) ## [What is an Electric Strike?](https://blog.dga.com/what-is-electric-strike) By: [Isabel Leckie](https://blog.dga.com/author/isabel-leckie) May 30th, 2024 Electric strikes are a common locking method used in modern access control systems. They consist of a hinged catch that releases to open the door when an authorized credential is presented to the reader. Electric strikes can be configured to be fail-safe or fail-secure, depending on the type of door they are installed on. Typically, electric strikes are configured as fail-safe to allow for safe exit from the premises. Although electric strikes operate on different hardware than magnetic locks, they follow the same principles of access control. [Read More](https://blog.dga.com/what-is-electric-strike) Share - Close - - - - [mailto:?body=https://blog.dga.com/what-is-electric-strike](mailto:?body=https://blog.dga.com/what-is-electric-strike) [![Blog Feature](https://cdn2.hubspot.net/hubfs/298890/blog-files/blog--cards-feature.png)](https://blog.dga.com/what-is-access-control-unit) [Access Control](https://blog.dga.com/topic/access-control) | [Security Terms](https://blog.dga.com/topic/security-terms) ## [What is an Access Control Unit?](https://blog.dga.com/what-is-access-control-unit) By: [Isabel Leckie](https://blog.dga.com/author/isabel-leckie) May 23rd, 2024 An Access Control Unit (ACU) is a panel to which all door-locking hardware (see Electric Strike and Mag Lock) and credential readers are connected. The ACU functions as the traffic controller as well as the primary power source for all the devices connected to the access control system. [Read More](https://blog.dga.com/what-is-access-control-unit) Share - Close - - - - [mailto:?body=https://blog.dga.com/what-is-access-control-unit](mailto:?body=https://blog.dga.com/what-is-access-control-unit) [![Blog Feature](https://cdn2.hubspot.net/hubfs/298890/blog-files/blog--cards-feature.png)](https://blog.dga.com/what-is-two-person-rule) [Access Control](https://blog.dga.com/topic/access-control) | [Security Terms](https://blog.dga.com/topic/security-terms) ## [What is a Two-Person Rule?](https://blog.dga.com/what-is-two-person-rule) By: [Isabel Leckie](https://blog.dga.com/author/isabel-leckie) May 16th, 2024 A two-person rule, also referred to as an escort rule, is a highly effective access control security measure that requires two authorized cardholders to be present in order to grant access to a specific area or item, such as a door or display case. This feature is often used to protect sensitive locations like specific doors, product storage areas, vaults and safes, and server rooms. By requiring the presence of two cardholders, the two-person rule ensures an added layer of security, minimizing the risk of unauthorized access or potential breaches. This feature is a great way to layer additional security elements to your physical access control system. While financial services firms, banks, jewelry businesses, cannabis growers and operators most frequently request these advanced features, they offer useful applications in many other types of businesses and buildings. [Read More](https://blog.dga.com/what-is-two-person-rule) Share - Close - - - - [mailto:?body=https://blog.dga.com/what-is-two-person-rule](mailto:?body=https://blog.dga.com/what-is-two-person-rule) [![Blog Feature](https://cdn2.hubspot.net/hubfs/298890/blog-files/blog--cards-feature.png)](https://blog.dga.com/what-is-credential-reader) [Access Control](https://blog.dga.com/topic/access-control) | [Security Terms](https://blog.dga.com/topic/security-terms) ## [What is a Credential Reader?](https://blog.dga.com/what-is-credential-reader) By: [Isabel Leckie](https://blog.dga.com/author/isabel-leckie) April 25th, 2024 A Credential Reader, also known as a Card Reader, captures an access credential's encoded data and transmits it to an Access Control Unit (ACU). The ACU then determines whether to grant or deny access based on the cardholder's access rights. [Read More](https://blog.dga.com/what-is-credential-reader) Share - Close - - - - [mailto:?body=https://blog.dga.com/what-is-credential-reader](mailto:?body=https://blog.dga.com/what-is-credential-reader) [![Blog Feature](https://cdn2.hubspot.net/hubfs/298890/blog-files/blog--cards-feature.png)](https://blog.dga.com/what-is-mobile-access-credential) [Access Control](https://blog.dga.com/topic/access-control) | [Security Terms](https://blog.dga.com/topic/security-terms) ## [What is a Mobile Access Credential?](https://blog.dga.com/what-is-mobile-access-credential) By: [Isabel Leckie](https://blog.dga.com/author/isabel-leckie) February 29th, 2024 A mobile access credential is a convenient app installed on your employees' smartphones that allows them to gain access to an access point by simply tapping or twisting their phones near the access point. This technology utilizes BLE (Bluetooth Low Energy) or NFC (Near Field Communication) which offers reliable and accurate access. Mobile access credentials widen your access control options beyond the more common access fobs and cards and can replace or supplement the use of physical access credentials. [Read More](https://blog.dga.com/what-is-mobile-access-credential) Share - Close - - - - [mailto:?body=https://blog.dga.com/what-is-mobile-access-credential](mailto:?body=https://blog.dga.com/what-is-mobile-access-credential) [![Blog Feature](https://cdn2.hubspot.net/hubfs/298890/blog-files/blog--cards-feature.png)](https://blog.dga.com/what-is-passive-infrared-sensor) [Access Control](https://blog.dga.com/topic/access-control) | [Security Terms](https://blog.dga.com/topic/security-terms) ## [What is a Passive Infrared (PIR) Sensor?](https://blog.dga.com/what-is-passive-infrared-sensor) By: [Isabel Leckie](https://blog.dga.com/author/isabel-leckie) February 22nd, 2024 A Passive Infrared (PIR) sensor is a type of motion sensor. This technology operates by detecting movement within a specific area by measuring the infrared radiation emitted by objects. [Read More](https://blog.dga.com/what-is-passive-infrared-sensor) Share - Close - - - - [mailto:?body=https://blog.dga.com/what-is-passive-infrared-sensor](mailto:?body=https://blog.dga.com/what-is-passive-infrared-sensor) [![Blog Feature](https://cdn2.hubspot.net/hubfs/298890/blog-files/blog--cards-feature.png)](https://blog.dga.com/what-is-door-forced-feature) [Access Control](https://blog.dga.com/topic/access-control) | [Security Terms](https://blog.dga.com/topic/security-terms) ## [What is a Door Forced Feature?](https://blog.dga.com/what-is-door-forced-feature) By: [Isabel Leckie](https://blog.dga.com/author/isabel-leckie) February 15th, 2024 The Door Forced Feature is an important part of an access control system. It is designed to activate an alarm if the door is opened without a valid access card being presented or an associated REX (Request to Exit) signal. This feature is especially useful in case of forced entry by criminals who may forcibly attempt to open the door. [Read More](https://blog.dga.com/what-is-door-forced-feature) Share - Close - - - - [mailto:?body=https://blog.dga.com/what-is-door-forced-feature](mailto:?body=https://blog.dga.com/what-is-door-forced-feature) [![Blog Feature](https://cdn2.hubspot.net/hubfs/298890/blog-files/blog--cards-feature.png)](https://blog.dga.com/what-is-local-door-sounder) [Access Control](https://blog.dga.com/topic/access-control) | [Security Terms](https://blog.dga.com/topic/security-terms) ## [What is a Local Door Sounder?](https://blog.dga.com/what-is-local-door-sounder) By: [Isabel Leckie](https://blog.dga.com/author/isabel-leckie) February 1st, 2024 A local door sounder is a siren device that provides an audio alert when a protected door is held open past a preset time period, typically 15-30 seconds. Its purpose is to promptly and effectively alert individuals that a door has been held open for an extended period. By doing so, it not only prevents unauthorized access but also ensures that the security of the premises remains intact. [Read More](https://blog.dga.com/what-is-local-door-sounder) Share - Close - - - - [mailto:?body=https://blog.dga.com/what-is-local-door-sounder](mailto:?body=https://blog.dga.com/what-is-local-door-sounder) [![Blog Feature](https://cdn2.hubspot.net/hubfs/298890/blog-files/blog--cards-feature.png)](https://blog.dga.com/what-is-request-exit-device) [Access Control](https://blog.dga.com/topic/access-control) | [Security Terms](https://blog.dga.com/topic/security-terms) ## [What is a Request to Exit Device?](https://blog.dga.com/what-is-request-exit-device) By: [Isabel Leckie](https://blog.dga.com/author/isabel-leckie) January 25th, 2024 A REX device, short for Request to Exit, is a device in access control systems that provides a simple and convenient way to exit through access-controlled doors. A REX device is required for any door secured with a magnetic lock (mag lock). This ensures that individuals inside a secured area can exit in an emergency. [Read More](https://blog.dga.com/what-is-request-exit-device) Share - Close - - - - [mailto:?body=https://blog.dga.com/what-is-request-exit-device](mailto:?body=https://blog.dga.com/what-is-request-exit-device) [![Blog Feature](https://cdn2.hubspot.net/hubfs/298890/blog-files/blog--cards-feature.png)](https://blog.dga.com/what-is-panic-hardware) [Access Control](https://blog.dga.com/topic/access-control) | [Security Terms](https://blog.dga.com/topic/security-terms) ## [What is Panic Hardware?](https://blog.dga.com/what-is-panic-hardware) By: [Isabel Leckie](https://blog.dga.com/author/isabel-leckie) January 11th, 2024 Panic hardware is a type of locking hardware designed to allow immediate exit at all times and is a crucial component of building safety. Its primary purpose is to provide a quick and efficient means of escape during emergency situations. Unlike traditional locking mechanisms, panic hardware allows individuals to exit a building swiftly without the need for any lever or knob rotations. The simplicity and reliability of panic hardware make it an indispensable part of any building's safety infrastructure. [Read More](https://blog.dga.com/what-is-panic-hardware) Share - Close - - - - [mailto:?body=https://blog.dga.com/what-is-panic-hardware](mailto:?body=https://blog.dga.com/what-is-panic-hardware) [![Blog Feature](https://cdn2.hubspot.net/hubfs/298890/blog-files/blog--cards-feature.png)](https://blog.dga.com/what-is-biometric-reader) [Access Control](https://blog.dga.com/topic/access-control) | [Security Terms](https://blog.dga.com/topic/security-terms) ## [What is a Biometric Reader?](https://blog.dga.com/what-is-biometric-reader) By: [Isabel Leckie](https://blog.dga.com/author/isabel-leckie) January 4th, 2024 Biometric readers scan an individual's unique morphological characteristics such as a fingerprint, palm, voice, iris, or face as a form of access control. Fingerprint and palm readers are the most popular choices due to their ease of use and high level of accuracy, but DGA also employs modern facial recognition readers, which are highly convenient and accurate forms of access control. [Read More](https://blog.dga.com/what-is-biometric-reader) Share - Close - - - - [mailto:?body=https://blog.dga.com/what-is-biometric-reader](mailto:?body=https://blog.dga.com/what-is-biometric-reader) [![Blog Feature](https://cdn2.hubspot.net/hubfs/298890/blog-files/blog--cards-feature.png)](https://blog.dga.com/what-is-fail-secure) [Access Control](https://blog.dga.com/topic/access-control) | [Security Terms](https://blog.dga.com/topic/security-terms) ## [What is Fail-Secure?](https://blog.dga.com/what-is-fail-secure) By: [Isabel Leckie](https://blog.dga.com/author/isabel-leckie) September 28th, 2023 Fail-secure refers to a locking mechanism that defaults to a secure or locked position when it experiences a failure or power loss. This is the opposite of fail-safe, which defaults to an open position when power is lost. [Read More](https://blog.dga.com/what-is-fail-secure) Share - Close - - - - [mailto:?body=https://blog.dga.com/what-is-fail-secure](mailto:?body=https://blog.dga.com/what-is-fail-secure) [Previous](https://blog.dga.com/tag/access-control/page/1) [All posts](https://blog.dga.com/all) [Next](https://blog.dga.com/tag/access-control/page/3) [![DGA Security](https://blog.dga.com/hubfs/Assets/logo/cropped-DGA-Security-Logo-nsr-1-1.png)](https://www.impactbnd.com) 429 West 53rd Street New York, New York 10019 ##### Contact Sales 800 PICK DGA (800-554-5599) sales@dga.com ##### Contact Customer Care [customercare@dga.com](mailto:customercare@dga.com) 800-221-2300 ##### [Business Security](https://www.dga.com/business-security/) - [Intrusion Alarms](https://www.dga.com/business-security/intrusion-alarms/) - [Video Surveillance](https://www.dga.com/business-security/video-surveillance/) - [Access Control](https://www.dga.com/business-security/access-control/) - [Security System Monitoring](https://www.dga.com/business-security/alarm-monitoring/) - [Environmental Monitoring](https://www.dga.com/business-security/environmental-monitoring/) - [Elevator Emergency Communication](https://www.dga.com/business-security/elevator-emergency-communication/) - [Nationwide Service](https://www.dga.com/business-security/nationwide-service/) - [The DGA Vault at 580 Fifth Avenue](https://www.dga.com/vault/) ##### [Fire Alarm Systems](https://www.dga.com/fire-systems/) - [Design and Installation](https://www.dga.com/fire-systems/design-installation/) - [Testing and Inspection](https://www.dga.com/fire-systems/testing-and-inspection/) - [Fire Alarm System Monitoring](https://www.dga.com/fire-systems/alarm-monitoring/) - [Contractor Support](https://www.dga.com/fire-systems/contractor-support/) ##### [Industries](https://www.dga.com/industries/) - [Art Galleries](https://www.dga.com/industries/art-gallery-security/) - [Banking and Financial](https://www.dga.com/industries/bank-security/) - [Cannabis](https://www.dga.com/industries/cannabis-security/) - [Hotels](https://www.dga.com/industries/hotel-security/) - [Jewelry](https://www.dga.com/industries/jewelry-security/) - [Nonprofits](https://www.dga.com/industries/nonprofit-security/) - [Offices](https://www.dga.com/industries/office-security/) - [Property Management](https://www.dga.com/industries/property-security/) - [Religious Institutions](https://www.dga.com/industries/religious-institution-security/) - [Restaurants](https://www.dga.com/industries/restaurant-security/) - [Retail](https://www.dga.com/industries/retail-security/) ##### [Tools & Training](https://www.dga.com/tools/) - [DGAConnect Login](https://connect.dga.com/) - [DGAOneVIEW Login](https://dgaoneview.com/login#) - [DGA Payment Login](https://payment.mydga.com/login.aspx) - [Free System Training](https://www.dga.com/free-system-training) ##### [About DGA](https://www.dga.com/company/) - [Blog](https://blog.dga.com/) - [Careers](https://www.dga.com/careers/) - [Credentials](https://www.dga.com/credentials/) - [Meet Business Insurance Requirements](https://www.dga.com/meet-business-insurance-requirements/) © 2026 DGA Security Systems, Inc. | [Privacy Policy and Terms of Use](https://www.dga.com/privacy-policy/)