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Alarms and notifications as part of a crowd security system

Original publication: GISUSER


To prioritize public safety Each crowd control security system should be set up in accordance with the requirements of state guidelines. Leaving out the detailed lighting of such notions as the rejection zone, the requirements for the manufacture of gates and turnstiles, we will dwell in more detail on the choice of perimeter alarms (if such is provided).

  1. The system must function sustainably in extreme soil and climatic conditions with high levels of electromagnetic interference.
  2. As part of the perimeter protection system, the system shall comply with the peculiarities of the fence and the adjacent territory (it should be noted that the range of selected systems can be expanded if the facility has the possibility of complete or partial conversion of the fence).
  3. Tactical and technical characteristics of the system should meet the requirements of the security as much as possible. Therefore, the system selection can be divided into three stages.

Stage 1 system selection


From set of the systems offered in the market (I), choose systems (II) which are steady against the external influences characteristic for the given protected object:

  • electromagnetic interferences
  • seasonal variations in temperature
  • heavy snowfalls, snowstorms, wet snow, ice etc.
  • to frequent dense fogs
  • hurricane winds, heavy rains, dust storms; seismic soil fluctuations

Stage 2 system selection


Of the many stadium security systems and social distance control systems selected in step 1, select systems (III) that match the features of the fence and the surrounding area:
  • the structural characteristics of the main fence
  • the vulnerabilities of the fence and the associated most likely means of overcoming them
  • the presence of a warning fence, the width of the rejection area
  • soil characteristics in the exclusion zone, presence of objects and structures interfering with the operation of alarm means
  • the length of straight fence sections
  • the presence of turns, curves of the fence, its height differences due to the terrain
  • the presence and nature of fence ruptures, both provided (gates, wickets) and forced (pond, rock, swamp, etc.)
  • the presence of vegetation in the perimeter zone and its character
  • the presence of railways or roads, pedestrian routes, power lines, pipelines, cable networks and communications near the perimeter
  • possible routes of animal migration.

Stage 3 system selection

At this stage, subset (III) selects systems (IV) with the best tactical and technical characteristics, the main of which are:

  • the probability of detection (i.e. the probability of an alarm being triggered when an intruder crosses the detection zone). It determines the tactical reliability of the guard boundary and should be at least 0.9
  • false alarm frequency (or mean time per false alarm). This characteristic largely determines the effectiveness of the system and is mainly dependent on climatic conditions and industrial disturbances. Acceptable for modern systems is the frequency of no more than one false alarm in 10 days per 250 m site
  • vulnerability of the system (i.e. possibility to overcome it). The lower it is, the harder it is to bypass it
  • reliability, ease of installation and operation concealability. This indicator is important because it deprives the intruder of information about the presence of the perimeter alarm system or about its type and principle of operation
  • the cost of one running meter of the security boundary (i.e., the total cost of equipment, sensitive elements, their installation and adjustment per meter of perimeter length);
  • maintenance adaptability, its frequency and volume
  • the duration of continuous round-the-clock operation
  • number of perimeter sections from which simultaneous reception of alarm signals is possible
  • accuracy and ease of localization of the place of violation
  • possibility of automatic switching on of security electric lighting and television system.

It is possible to make this conclusion: there is no universal system optimal for any perimeter and any operating conditions. Therefore, the choice of perimeter alarm system should be based on the main task: to ensure the maximum possible protection of the object.


That is why it is desirable to study all the parameters of future systems andanalysis of situations in order to make appropriate management decisions at the stage of designing security measures. One of the most important is video surveillance and video recording systems.