Outdoor Perimeter Security Sensors & Systems

Outdoor security sensors detect intruders as soon asmanagement should be a consideration. A security
they enter a protected area and before they canmanagement system integrates and automates the
gain access to people or valuable assets.control of the sensors and sensor alarms, significantly
In a correctional environment, security sensors canreducing the workload of the operator. These
be used to immediately detect prison escapesystems can provide maintenance information to help
attempts. A quality outdoor security systemdiagnose problems with individual sensors and allow
demonstrates a significant return on investment bysensors to be adjusted from the central control.
reducing the risk of theft, damage or personal injury.Outdoor sensor types:
Outdoor sensors can be used either to complementMany types of outdoor sensors exist in the market.
indoor security sensors or as primary security inThe most appropriate sensor to use depends on
situations where indoor security is not feasible. Ableseveral factors: perceived threat and level of
to protect assets at both manned and unmannedprotection required; effectiveness of the sensor
sites, outdoor security sensors are a practical solutionagainst the threat; site conditions and environment;
for remote sites where guards are not a viablesensor cost-comparisons; and the life cycle or cost of
alternative.ownership of the sensor. Outdoor sensors can be
Outdoor sensors face challenges not found in indoorclassified into four groups: volumetric sensors,
security situations. Environmental conditions, such asfence-mounted sensors, video motion detection
temperature extremes, rain, snow, animals, blowingsensors and barrier sensors.
debris, seismic effects, terrain and traffic, must all beVolumetric Sensors
taken into account. When functioning under theseVolumetric sensors generate an invisible detection
adverse conditions, the system must continue tofield that locates intruders moving through that field.
maintain a high probability of detection whileAs the field of detection is invisible, these sensors
minimising false alarms (alarms with unknown causes)are very difficult to evade. Immune to most
and nuisance alarms (environment-related alarms),environmental conditions, these sensors are often
both of which can reduce confidence in the securityused in sterile zones and may be totally covert.
system's performance.Fence-Mounted Sensors
The "vulnerability to defeat" characteristics ofFence and wall-associated sensors are above ground
different sensors is important to consider. The hiddendetection sensors that are attached to an existing
nature of totally covert sensors makes them difficultfence or wall. They detect intrusion when an intruder
to avoid and less subject to vandalism. Intruders aredisturbs the detection field or when vibration due to
not even aware of their presence. On the othercutting or climbing on a metal fabric fence causes an
hand, some sensors present an imposing appearancealarm.
that can provide a deterrent effect. VolumetricVideo Motion Detection Sensors
sensors create a large invisible detection field thatA Video motion detection system transforms the
makes bridging difficult.assessment-only ability of CCTV cameras by
Closed circuit television (CCTV) cameras are ananalysing the video output signal to create the
important element in outdoor security. CCTVdetection field. Video Motion Detection also provides
assessment is used to verify whether or not alarmsadditional information to help identify the source of
reported by intrusion detection sensors are validan alarm and whether or not it is valid.
intrusions or false / nuisance alarms, ensuring thatBarrier Sensors
only valid alarms are responded to. Use ofBarrier sensors are a two-in-one security option. They
assessment is especially important for remote sitesprovide both a barrier to intrusion and a sensor
where response to nuisance alarms can be particularlysystem for detection. Taut-wire sensors are an
costly.example of a barrier sensor that offers an almost
Security Management Systemzero False Alarm Rate and unsurpassed Probability of
Whether security requirements call for sensors inDetection. These sensors have virtually no
stand-alone detection, or combined with CCTVenvironmental limitations and are able to provide
assessment in an integrated system, securityreliable service for many years.