Components of Physical Security
Physical security describes security measures whose aim is to deny unauthorized access to resources, equipment, and facilities while at the same time protecting property and personnel from damage or harm, respectively.
Such events can include vandalism, fire, terrorism, floods, burglary, and theft.
It involves the employment of multiple layers of interdependent systems working in concert, some of which can include alarm and intruder detection systems, CCTV surveillance systems, protective barriers, security guards, access control, fire protection, and deterrence systems.
The main aim of physical security systems is to
- Deter potential intruders, e.g., through the use of perimeter marking, warning signs, and security lighting.
- Detect and flag intrusions, as well as monitor and record potential intruders, e.g., through the use of intruder detection systems and CCTV surveillance cameras.
- Trigger appropriate intruder response and action, e.g., deployment of security guards and notifying the police.
The onus is on security stakeholders, i.e., security designers, architects, vendors, and analysts, to analyze the costs of specifying, implementing, and maintaining the overall infrastructure while at the same time balancing it with broader issues such as human safety and rights, aesthetics, and general societal conventions.
While the principles are similar, different sites and contexts require a different approach to physical security planning and implementation. Measures that are appropriate for a high-security facility like a prison would be unfit for a home or an office block, and vice versa.
Components
A complete physical security system has four distinct components:
- Deterrence: barriers, walls, and cameras at entry ways are meant to deter and dissuade potential intruders from carrying out their intended activities.
- Detection: alarm systems are meant to detect intrusion or anomalies and promptly issue distress signals for response.
- Delay: Access Control Systems can be used to delay, impede, forestall, or isolate intruders or secure areas whenever an intrusion is detected.
- Response: Security personnel or the police respond to an alarm system distress signal and can use security cameras and access control systems to manage and coordinate response.
Deterrence methods
The main aim of a deterrence system is to dissuade and thwart a potential intruder from attempting to intrude into a facility or carry out whatever activity they had in mind.
Some of them include warning signs, perimeter walls, vehicle barriers, security lighting, and trenches, among others.
Physical barriers
Perimeter walls, fences, and vehicle barriers are the outermost layer and act as the first line of defence. Seemingly insurmountable physical barriers act as a deterrent while also actively preventing or, at the very least, delaying an attack on secured premises.
Examples of this can include tall perimeter walls with an electric fence or razor wire and spikes, coupled with warning signage warning of the dangers of attempting a breach.
In contexts where tall perimeter walls and razor wire are impracticable or unaesthetic, such as an office block, the outermost layer will have to be the walls, doors, and windows of the building itself.
Security lighting
Intruders are less likely to venture into well-lit areas for fear of being easily spotted.
Entrance and exit points, such as gates, doors, and windows, should be well-lit to allow close and clear observation of movement and activities.
A good practice when installing security lighting is to have widely distributed low-intensity lighting that blankets the whole facility evenly rather than a few patches of intense lighting, since the latter usually means that there are blind spots for security guards and surveillance cameras, which potential intruders can take advantage of.
Installed lights should be made as tamper-proof as possible, e.g., by installing them on tall poles or walls where accessibility is almost impossible.
Additional measures such as hooking security lights to backup power can ensure the area is still lit whenever there is a power failure, which is when the facility can be most vulnerable.
Electronic Surveillance and Intrusion Detection
CCTV and Video Surveillance
When placed and installed conspicuously, CCTV cameras are often an effective deterrent.
Their main aim, though, is to assist with live monitoring and incident assessment or historical analysis.
When working together with alarm systems, CCTV cameras can help with immediate incident assessment and help coordinate reaction and response as events can be viewed in real-time without a security guard having to be physically present at the source of the alarm trigger to assess the risk.
Security cameras by themselves do not necessarily guarantee human response unless there is dedicated human monitoring of the situation. In this case, the video monitoring gathers evidence for later analysis. Advanced surveillance systems, though, have the ability to raise an alarm or send real-time push notifications whenever they detect an intrusion or any preset anomaly.
Alarm systems and sensors
Alarm systems, including sensors such as perimeter motion and vibration sensors, contact sensors, and glass break sensors, alert security personnel when an intrusion is attempted or in progress.
Working in concert with physical systems, they can help dissuade or thwart an attempted intrusion. Loud-blaring sirens and flashing strobe lights can attract public attention, which is the last thing an intruder would want.
For an alarm and intrusion detection system to be useful, the response time to a triggered alert must be prompt and swift.
For high-value targets, potential attackers sometimes test an alarm system’s effectiveness by purposely triggering it and then observing the response time from security personnel. This can inform them whether they can successfully carry out an attack and get away before the alarm is responded to by relevant authorities.
Access Control
Access control systems monitor and control traffic through specific access points and areas of a secured facility. An access control system can include a conglomeration of systems such as biometric readers, security cameras, turnstiles, boom barriers, locks, doors, and, of course, security guards.
Mechanical access control systems
These can include gates, doors, turnstiles, and locks.
Mechanical systems can work in small facilities, but in large facilities, they can become cumbersome and hinder the movement of staff and personnel. In such cases, electronic access control systems are the next logical option.
Electronic access control systems
Electronic access control systems manage the movement of personnel within a facility without direct human input. They include:
- Access credentials, such as cards, fobs, and badges, are used to identify personnel as they seek access or egress within a facility. These are swiped or held in close proximity to the access control panel and readers placed at strategic points within the facility, i.e., entries and exits.
- Locking hardware such as electromagnetic locks, electric strikes, and smart locks grant access or egress whenever the right credentials are presented to the linked card readers. Boom barriers and turnstiles can also be considered part of this.
- Linked alarms can trigger distress signals whenever unauthorized or forced access or exit is attempted.
- Management software controls the actions of all the electronic security devices that make up the whole access control infrastructure. It’s used to preset, configure, and manage access permissions, as well as keep and analyze records of all movement activity.
Security Personnel
Security personnel still play a central role in all layers of security.
Electronic and mechanical security systems would be of little use if security personnel weren’t trained on how to handle and maintain their operations.
An alarm system is only useful if security personnel are trained to respond to a particular distress signal, identify the source, and use other related systems like CCTV cameras to scan the facility and analyze footage, or an access control system to initiate a lockdown or evacuation procedure.
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