Defending the boundaries of your site

Often the phrase ‘perimeter protection’ conjures images of sites in the middle of nowhere with extensive fencing surrounded by open fields.

However, in an urban context, perimeter protection could be your doors, windows, locks and access control systems. The foyer of your building could be a semi-public space – in the sense that it’s accessible to anyone who walks in – in which case the security “perimeter” could be the access control gates, doors or other points of access to your organisation’s private space.

For the purposes of this article, we will look at methods and technology for protecting the areas of your perimeter that are not generally considered to be access points, eg the fence line, exterior walls of your building and windows.

Hostile vehicle mitigation
One of the hottest topics in perimeter protection is hostile vehicle mitigation (HVM), the control of vehicles being used by criminals or terrorists to penetrate your site boundary.

It’s not enough to erect barriers and hope for the best. Solutions for HVM need to be holistic, integrated and multi-layered, according to the Perimeter Security Suppliers’ Association (PSSA).
In a recent blog post, the PSSA’s Stephen Munden wrote that it is necessary to consider all threats to a site and its operations and then integrate the security measures into the total scheme for the site – traffic movement, the environment, site use, and the building’s management system being examples.

Physical countermeasures will always play a big part, acting as a first line of hard defence, often protecting further but possibly weaker measures within. When procuring perimeter security equipment, it is vital to ask what is the process in which the equipment participates?

It is important to consider the vehicle security barrier or security fencing as a physical system within the overall security management system. Control cabinets and containers, for example, which form part of the system can also be vulnerable to vehicular or manual attack. An increasing concern, as new technology is adopted, is the vulnerability to interference by cyber or remote means, which could impact the security integrity of the HVM measures.

As highlighted in the Export Security Strategy, the UK is fortunate to have a wealth of experience and expertise in developing security risk mitigation. Basic advice can be found in CPNI and NaCTSO publications online. Usually, however, it will be necessary to seek specific advice from CPNI, qualified security consultants, or those who design the HVM systems, such as members of the PSSA.
The PSSA has developed a verification scheme to help raise industry performance and provide confidence to perimeter security system buyers. The PSSA says its scheme is unique because it offers validation against all relevant standards and legal requirements, unlike schemes which only assess compliance to a single standard. Verification means that a supplier of a high security product such as an anti-ram vehicle barrier is able to consistently manage the manufacture of its product and maintain standards.
For the end-user, certification means that you can buy with confidence, says the PSSA, with the assurance that the product you purchase will protect against physical attacks and meet legal and industry standards.

While it’s still early days for the scheme and many companies are still working through the verification process, products verified so far include a range of vehicle barriers from Broughton Controls, ATG Access, Frontier Pitts and Cova Security Gates.

PDFs of the verification certificates are available on the PSSA Verfiication Scheme website at and provide details of the standards met and testing regimes to which the manufacturers have submitted their products.

Windows protection
Emergency doors are a notable point of weakness with a number of museums having lost valuable paintings after thieves gained access this way. At the Kunsthal Museum in Rotterdam in October 2012, three thieves broke in through a rear emergency exit of the museum, grabbing seven paintings off the wall and fleeing within minutes. The paintings have never been recovered and may have been burned. One of the thieves testified in court that security had been practically non-existent and they had prised open the emergency door with a screwdriver.

In other cases, thieves have broken in through windows. Typically these smash and grab raids are over in minutes, underscoring the vulnerability of windows as a point of access.
More expensive than normal glass, laminated security glass is comprised of two or more layers of glass sandwiched together with a plastic interlayer. While someone may shatter the glass layers, the interlayer is highly resistant to penetration, preventing or at least significantly delaying entry.

Weight is an issue with laminated glass as is the strength of the frames into which it is installed. Depending on its thickness and attack resistance rating, laminated security glass can weigh between 50 and 100kg per square metre. Window frames must be designed to support this weight and also be attack resistant themselves – there’s no point in putting in extra strong glass only to have it defeated by an attack on the frame itself.

Another potentially less expensive solution is the use of window films. According to the Glass and Glazing Federation, window film combined with anchorage and containment systems can help protect against smash and grab raids by significantly increasing the time it takes to penetrate a window.

In its most basic form, perimeter protection is about deterring, detecting and delaying attackers and intruders, but the exact function of your perimeter protection system will depend on your operational requirement.

Leave a Comment

You must be logged in to post a comment.