#perimeter alarm
Specifics of building perimeter security systems.
Specifics of building perimeter security systems
The article offered to your attention opens a series of publications devoted to the effective use of modern technical security means (TSM), primarily perimeter ones, in security systems of various objects. Since the price of perimeter complexes is quite high, the authors pay much attention to recommendations for the optimal construction of systems taking into account the specific features of objects.
Classification of security objects
By the degree of importance, and therefore the reliability of security, objects are usually divided into categories, for example: especially important (0B), important, general purpose, etc.
The consequences of the actions of violators are assessed by the degree of damage caused to the facility, the environment, and public structures.
The impact of intruders on hazardous facilities (some military, nuclear, fuel and energy facilities, chemical and other enterprises with hazardous production) can lead to serious, irreparable consequences associated with harm to the health and life of people, the environment, etc. Such damage often cannot be assessed in monetary terms.
Violators' actions at industrial and commercial facilities (IC) can lead to damage, which is usually estimated in monetary terms.
Features of security tasks for various types of facilities
In case of penetration into the 0B, the most likely actions are sabotage aimed at destroying the facility, disrupting its normal functioning, as well as actions related to the theft of nuclear materials, weapons, classified information, and the amount of damage may increase over time (for example, an increase in the number of victims as a result of an explosion at a nuclear-hazardous facility).
In case of unauthorized penetration into PC facilities, the most likely actions are those with selfish goals, and only in some cases — sabotage, and the amount of damage tends to decrease over time.
In accordance with the above, the actions of security forces at 0B and other facilities have some specific features, the essence of which is as follows.
At OV facilities, the intruder must be neutralized without fail before he carries out the intended action.
At PC facilities, the intruder (if this is not related to sabotage or an act of terrorism) can be neutralized both before and immediately after the action is carried out.
Another important factor determining the specifics of the tasks of the facility security system is the initial position of the intruder.
At 0B facilities, the intruder (external) is located outside the facility's territory, and the presence of outsiders in the protected area is absolutely unacceptable. The category of internal intruders is not considered here, since identifying individuals prone to various illegal actions from among the facility's employees is the function of the facility's security service and is beyond the scope of this article.
At PC facilities, a potential intruder, in principle, has the right to be on the protected territory and cannot be identified as an intruder until any unauthorized actions have been initiated.
General principles of ensuring the security of facilities
In general, securing a facility consists of implementing two principles:
• identifying and assessing threats to the facility;
• developing and implementing adequate security measures.
The measures include:
• total control of unauthorized entry into the facility, buildings and premises;
• restriction and control of people's access to «closed» buildings and premises with the ability to document the results of the control;
• detection of the intruder at the earliest stages of his advancement toward the target of the action;
• assessment of the situation;
• creation of physical obstacles on the intruder's path, ensuring the delay necessary for security forces to intercept him;
• taking immediate action to deploy security forces and stop the intruders' action;
• video documentation of personnel actions in particularly critical areas of the facility.
A significant role in ensuring the implementation of the measures considered is given to perimeter security systems.
Some features of the perimeter security design
The perimeter line, running along the outer border of the facility's territory, is the first and mandatory one in the security system.
Perimeter security means (PS) are used in cases where:
• a clearly regulated zone must be organized around the facility to ensure the possibility of adequate influence on intruders in order to neutralize them on the approaches to the security facility;
• it is necessary to clearly delineate the boundaries of the facility’s territory, including to improve discipline and order at the enterprise.
Usually, perimeter security means are used together with fences that mark the boundary of the object's territory and thus create a certain zone around it to ensure the possibility of adequate influence on the intruder to neutralize him, that is, to ensure the legal legitimacy of the security actions inside the fenced area.
The following fact speaks in favor of the need to construct perimeter alarm boundaries for both 0V and PC objects.
The absence of perimeter alarm boundaries may result in the intruder being detected untimely and the security forces simply not having enough time to neutralize him. In addition, the boundaries prevent the unauthorized removal of material assets from the facility.
Functional security zones
When organizing perimeter security of a facility, its internal territory (protected area) should be conditionally divided into several functional zones: detection, observation, containment, destruction, in which the corresponding technical means are located.
Detection zone (30) — the zone in which the perimeter security systems are located, which automatically detect the intruder and issue the «Alarm» signal. The cross-sectional dimensions of the zone can vary from several centimeters to several meters.
The observation zone (ZN) — is designed to monitor the situation on the approaches to the boundaries of the protected zone and in its space, starting from the boundaries, using technical means (television, radar, etc.).
The physical containment zone (PZ) is designed to detain an intruder while moving toward a target or escaping. It is organized using engineering barriers that create physical obstacles to the intruder's movement. Engineering barriers are various types of fences, canopies, spirals of barbed tape and wire, ditches, mechanical detaining barriers, etc.
It should be noted that in many cases, 30 and PZ are combined.
The zone of physical neutralization and destruction (ZNP) is intended to neutralize and destroy attackers, respectively. In most cases, it is located in the 30th and ZFS. This zone contains means of physical influence, which are generally divided into electric shock, blinding (flashes), stunning, suffocating, restricting the ability to free movement (quick-hardening foam), means of neutralization and destruction — firearms, minefields, etc.
Optimization of the construction of the SSB
At first glance, it seems that security tasks can be effectively solved by moving the outer fence away, since in this case the intruder will need more time to cover the distance to the target and, accordingly, more time is left for the security forces to act. However, in this case, the perimeter of the facility is extended. Accordingly, the costs of technical equipment and their operation increase, as well as the required number of security forces.
Fig. 1. An example of the use of detection means of various types in the perimeter sections of a conventional facility
Thus, when constructing an effective security system (SS) for a facility, it is necessary to solve the problem of optimizing the configuration and length of the perimeter, the number of boundaries, the choice of security systems, physical barriers (PB), means of neutralization and destruction, deployment of security personnel, etc.
In practice, in the overwhelming majority of cases, we have to deal with a real existing object, and not with a designed one. Therefore, when building a security system, the main task is to minimize the costs of creating and operating the security system, the FB and maintaining security personnel with a given protection efficiency and features (configuration, length, etc.) of the existing perimeter.
The problem of theft of material assets that are thrown over the perimeter fence is relevant for many enterprises. The obvious, but not always the best, ways to solve it are to increase the height of the fence or the distance to the barrier from the inside. It is often more expedient to use perimeter security guards for this purpose, located on the inside of the fence at the maximum distance from it. Such a location of the security guards provides the best conditions for detaining both intruders trying to throw material assets outside the facility or leave the protected area with them, and external intruders.
This is explained by the fact that, based on the order in which the security systems located at different boundaries are triggered, the security forces can determine the direction of the intruder's movement.
Organizing a single perimeter security system for an enterprise that includes several facilities located on a designated territory and linked by a single technological cycle is economically feasible if the protection of individual facilities in total is more expensive than the overall perimeter.
When deciding on the creation of perimeter security, it should also be taken into account that its absence at an enterprise, which includes several buildings, does not allow the implementation of conditions on the allocated territory that ensure the guaranteed implementation of its jurisdiction. In this case, the intruder has the ability to quietly move material assets from the territory of the enterprise to the outside space, which is classified as theft.
An additional argument in favor of the decision on organizing perimeter security is that it is an essential component of the overall system, without which it is impossible to organize an effective access system to the enterprise. Its presence provides a complete guarantee of entry and exit of personnel exclusively through regulated checkpoints. This is also one of the necessary conditions for organizing effective accounting of the working time of the personnel of an enterprise consisting of several buildings located on a single territory, but not connected by covered passages.
A significant factor hindering the creation of a perimeter security system for PK objects is its relatively high cost. For reasons of economic feasibility, it is accepted that perimeter security of PK objects is necessary where its cost does not exceed 10% of the value of the protected material assets. Therefore, it is necessary to carry out a detailed justification of the composition and structure of the construction of a complex of technical means of the perimeter security line, based on possible threats, models of intruders and the concept of organizing counteraction. These issues are planned to be presented in subsequent articles.