Our security solutions start on the outside of the perimeter, creating early boundaries of detection that give our customers a proactive edge. We leverage video-analytic solutions to monitor external regions of interest combined with 24/7 remote guard monitoring, voice-down communication to trespassers and police dispatch requests to provide the most progressive security support at a fraction of on-site security costs.

IntranetsIntrusion Detection SystemsIntrusion Detection SystemPerimeter Security
Alarms Intrusion Detection Systems∗

Frank Davies CHS-IV, CIPS, CVI, in Effective Physical Security (Fifth Edition), 2017
Perimeter Protection

Perimeter protection is the first line in the defense to detect an intruder. The most common points equipped with sensing devices for premise perimeter protection are doors, windows, vents, skylights, or any opening to a business or home. Since over 80% of all break-ins occur through these openings, most alarm systems provide this type of protection. The major advantage of perimeter protection is its simple design. The major disadvantage is that it protects only the openings. If the burglar bursts through a wall, comes through the ventilation system, or stays behind after closing, perimeter protection is useless.


Door switches. These are installed on a door or window in such a way that opening the door or window causes a magnet to move away a contact switch, which activates the alarm. They can be surface mounted or recessed into the door and frame. A variety of types of switches are manufactured for all types of doors and windows. The switches are both wide gap type and magnetic standard type.

Glass break detectors. These detectors are attached to the glass and sense the breakage of the glass by shock or sound. Glass breakage sensors use microphone transducers to detect the glass breakage. A ceiling sensor over a window covers a 30-degree radius.

Wooden screens. These devices are made of wooden dowel sticks assembled in a cage-like fashion no more than 4 inches from each other. A very fine, brittle wire runs in the wooden dowels and frame. The burglar must break the doweling to gain entry and thus break the low-voltage electrical circuit, causing the alarm. These devices are used primarily in commercial applications.

Window screens. These devices are similar to regular wire window screens in a home except that a fine, coated wire is a part of the screen. When the burglar cuts the screen to gain entry, the flow of low-voltage electricity is interrupted and causes the alarm. These devices are used primarily in residential applications.

Lace and panels. The surfaces of door panels and safes are protected against entry by installing a close lace-like pattern of metallic foil or a fine brittle wire on the surface. Entry cannot be made without first breaking the foil or wire, thus activating the alarm. A panel of wood is placed over the lacing to protect it.

Interior sensors. They come in many shapes and sizes depending upon the application, for example, interior motion detector units and proximity and boundary penetration.

Alarm System Fundamentals

Doug Durant, Kevin Pound, in The Professional Protection Officer, 2010
Alarm Sensors

A basic alarm system is divided into three layers: perimeter protection, area protection, and spot protection. Perimeter protection is the first line of defense to detect a potential intruder. Alarm sensors on the perimeter are typically mounted on doors, windows, vents, and skylights. Since a vast majority of burglaries are committed using such openings, it is important that they be a priority for protection. Commonly used perimeter sensors include the following:

Glass-break sensors. These detect the breaking of glass. The noise from breaking glass consists of frequencies in both the audible and ultrasonic range. Glass-breakage sensors use microphone transducers to detect the glass breakage. The sensors are designed to respond to specific frequencies only, thus minimizing such false alarms as may be caused by banging on the glass.

Balanced magnetic switch. Balanced magnetic switches (BMSs) are typically used to detect the opening of a door, window, gate, vent, skylight, and so on. Usually, the BMS is mounted on the doorframe, and the actuating magnet is installed on the door. The BMS has a three-position reed switch and an additional magnet (called the bias magnet) located adjacent to the switch. When the door is closed, the reed switch is held in the balanced or center position by interacting magnetic fields. If the door is opened or an external magnet is brought near the sensor in an attempt to defeat it, the switch becomes unbalanced and generates an alarm.

Area protection is also sometimes called volumetric protection. The sensors used for this purpose protect the interior spaces of a business or residence. These devices provide coverage whether or not the perimeter is penetrated and are especially useful in detecting the “stay-behind” criminal. As a general rule, area sensors may be active or passive. Active sensors (such as microwave) fill the protected area with an energy pattern and recognize a disturbance in the pattern when anything moves within the detection zone.

By contrast, active sensors generate their own energy pattern to detect an intruder. Some sensors, known as dual-technology sensors, use a combination of two different technologies, usually one active and one passive, within the same unit.

Sensors used for area protection include the following:

Microwave motion sensors. With microwave motion sensors, high-frequency electromagnetic energy is used to detect an intruder’s motion within the protected area.

Passive infra-red (PIR). These motion sensors detect a change in the thermal energy pattern caused by a moving intruder and initiate an alarm when the change in energy satisfies the detector’s alarm criteria. These sensors are passive devices because they do not transmit energy; they monitor the energy radiated by the surrounding environment.

Dual-technology sensors. To minimize the generation of alarms caused by sources other than intruders, dual-technology sensors combine two different technologies in one unit. Ideally, this is achieved by combining two sensors that, individually, have high reliability and do not respond to common sources of false alarms. Available dual-technology sensors combine an active ultrasonic or microwave sensor with a PIR sensor.

Spot protection is used to detect unauthorized activity at a specific location. It serves as the final protective layer of a typical alarm system. Assets most commonly secured with spot protection include safes, vaults, filing cabinets, art objects, jewelry, firearms, and other high-value property. These sensors (sometimes referred to as proximity sensors) detect an intruder coming in close proximity to, touching, or lifting an object. Several different types are available, including capacitance sensors, pressure mats, and pressure switches.

Capacitance sensors. These detect an intruder approaching or touching a metal object by sensing a change in capacitance (storage of an electrical charge) between the object and the ground. A capacitor consists of two metallic plates separated by a dielectric medium (an insulating substance through which electric charges can travel via induction). A change in the dielectric medium or electrical charge results in a change in capacitance, and thus an alarm.

Pressure mats. Pressure mats generate an alarm when pressure is applied to any part of the mat’s surface. For example, an alarm is triggered when someone steps on a mat. Pressure mats can be used to detect an intruder approaching a protected object, or they can be placed by doors or windows to detect entry. Because pressure mats are easy to bridge, they should be well concealed, such as hidden beneath carpeting.

Pressure switches. Mechanically activated contact switches can be used as pressure switches. Objects that require protection can be placed on top of the switch. When the object is moved, the switch actuates and generates an alarm. Naturally, in such applications, the switch must be well concealed. The interface between the switch and the protected object should be designed so that an intruder cannot slide a thin piece of material under the object to override the switch while the object is removed.

What Is Perimeter Security? Posted on December 13, 2020 by Joy Dice
If you’re hoping to protect high dollar equipment or keep people at a distance from high-security areas that contain sensitive information, you need quality perimeter security.

Unfortunately, many companies believe a simple fence will get the job done. In most cases, a fence alone isn’t enough. While they do have their place in offering security, their protection level isn’t always sufficient to do the job.

At Security Alarm Company, one of our specialties is ensuring you have the right perimeter protection system to have adequate perimeter security.
More About Perimeter Security

Perimeter security also referred to as perimeter protection, is a security solution utilizing technology to secure a property’s perimeter or site from unauthorized access.

Generally speaking, perimeter security is exactly what you‘d think — security fencing and gates. However, advanced technology takes it a step further to integrate additional barriers giving you added protection and security against intrusion.

This level of protection works seamlessly with access control and video surveillance as well.

3 Types of Perimeter Security
Security Fence

Security fences are a basic security stable used to protect large areas on your property. Security fences designed for commercial perimeter protection can often withstand cutting the fence and even vehicles attempting to drive through it.

You get long term value for your initial investment
It can offer an appealing aesthetic to the property
It’s an easy way to help safeguard your property and employees against unwanted guests

Infrared Light Beam Detectors

A device is mounted on one end of a fence row, and the other is mounted at the opposite end. When the devices are activated, an infrared light connects the two ends creating the invisible light beam. If someone or something walks through a light beam, the alarm is tripped, alerting authorities of the breach.

With several light beams along each fence line, it drastically decreases someone’s chances of making it onto your property.

New Video Motion Detection

Capturing intruders on camera is imperative for perimeter protection. The latest in video technology now allows video surveillance to only send alerts when it distinguishes that the motion is from a Human or a Vehicle. You can utilize this enhanced video technology independently of any other system or incorporate it with your other perimeter protection systems for added security.

e visual evidence of what’s happening in the area
You will ONLY receive alerts when the motion is caused by a human or vehicle
Eliminate spending HOURS searching for events in footage; cut search times down to 2 minutes instead of 2 hours.