Electronic access controls can pose both physical and psychological barriers and should be capable of recording details of access for audit (for example, time and date of arrival and departure). Unlike mechanical locks, electronic keys can be deactivated when lost or stolen. Electronic access systems can also alert security personnel of potential breaches. As these controls may be expensive, such options as personal recognition, use of I.D. cards, and mechanical locks should be considered first.
The process of allowing or denying access can generally be accomplished through the following four approaches:
- A security guard controls the entry, and ID cards or other means of identification may be checked.
- A special ID card or badge with automatic reader (credential-based design).
- A PIN number for entering on a keypad (knowledge-based design).
- A biometric device for feature recognition.
Access control technology eliminates the need to replace mechanical locks and keys in response to every event that might compromise building security. A school can simply cancel the authorization of the access-control card in question and issue new cards when necessary.
Strategically located closed-circuit television (CCTV) cameras can provide surveillance of entry points and other vulnerable areas and assist in the assessment of events, alarms, or access violations. CCTV can also support access control by providing a psychological deterrent. Video records may serve as an aid for investigating incidents of unauthorized access. Moreover, CCTV can be used for evaluating and improving access control methods and procedures by providing recorded information on critical events. Alternative measures, such as guards or patrolling officers, should be planned when the CCTV is out of service.
Electronic Intrusion Detection
Intrusion alarms are sensors that detect break-ins or forced entries into a facility. Intrusion alarms have two principal functions: to detect intruders after-hours or in controlled areas, and to signal monitoring personnel when a security event is occurring. These alarms are available in many different types. Door contacts monitor doors; glass break detectors assure an alarm is sounded if a window is broken; and passive infrared sensors respond by sensing body heat. Sensitive microphones incorporated into the system allow a monitoring station to hear the movement and conversation inside the school and relay that information to a security force. Well-designed security systems are engineered in such a manner that they employ the sensors that best fit the requirements of a particular installation. A good security system design focuses on high functional reliability and immunity to false alarms, and should incorporate modular components and simple operating elements.
Every alarm system has three main components:
- Detectors: Used to detect an intrusion into the protected area. Passive infrared (which detects radiated heat of an object) and/or microwave (which detects motion) detectors are most appropriate for most schools.
- Control panel: Monitors the status of the detectors and processes any alarm condition in order to activate the signaling.
- Signaling: Indicates an alarm condition. The most common signaling device is a sounder and strobe, and/or digital communicators. The alarm information is sent to a monitoring station for verification prior to notifying the relevant authorities.
Integrating Security and Building Automation
“Smart Buildings,” in which security and building controls, such as lights and HVAC, interoperate, have been touted for years. Unless building controls serve life-safety functions, most experts advise their clients to integrate only intrusion detections, surveillance, access control, emergency response, and life safety systems. However, more and more manufacturers are seeking ways to link HVAC, life safety, fire, digital video, intrusion detection, access control, and asset locator pieces, and to track everything in real time.
Want to learn more? Check out Building & Renovating Schools, by Drummey Rosane Anderson, Inc., and contributing authors, available through RSMeans.