Useful Online CPTED ToolBy Ethan Ace, Published on May 23, 2012
While CPTED is often ignored in designing security systems, it offers significant value. CPTED, that is, Crime Prevention through Environmental Design, can reduce the opportunity for crime and the installation and maintenance costs required by extensive security systems. British organization Secured By Design has released an online planning tool [link no longer available] for those building residential blocks to provide guidance for these concerns. In this update, we overview the tool, and show practical examples of environmental improvements which impact surveillance systems.
The Secured By Design Toolkit [link no longer available] walks users through 15 separate scenarios in the design of a small residential housing block, both single-family rowhomes and multi-tenant housing. Examples for parking, access, play areas, lighting, and more are given, first showing the "wrong" design, followed by SBD's recommendations, based on CPTED principles, along with explanations for each. For those unfamiliar with CPTED, this is a good example of many of its principles.
Applications for Video Surveillance
Most of the recommendations given in the tool are not explicitly systems-related, as CPTED is based more on psychology and human behavior, but some of the examples given may have benefits for video surveillance.
Landscape Obstructing View
For example, in this scenario, shrubs have grown too tall, and tree canopies are left too low to the ground, obstructing residents' views of outdoor areas, and potential wrongdoing:
This is a common issue in surveillance, as well, as camera mounted at 12-15' on these buildings would be obstructed by trees, and the shrubbery provides plenty of hiding spots for criminals. The recommendations are trimming of the shrubs to 1m and keeping tree canopies above 2m for proper view, seen in this image:
Coverage of Access Routes
In this second example, pedestrian and vehicular access roads allow multiple routes into the parking area, and rear garden access, while limiting surveillance by residents with high walls and trees.
In the updated example, only a single road accesses parking, ending in a cul-de-sac. As a result, only residents and their guests should use the access road, greatly limiting the number of vehicles entering. Additionally, pedestrian paths are private, restricted to resident use, to limit foot traffic and rear garden access:
This redesign may also help camera coverage, as only one entry/exit must be covered, and the changed shape of the parking areas allows for greater visibility.
In this last example, the parking area is lit with only low lighting bollards, providing little light, and creating shadows.
The ow light level plus variations between light and shadow make for poor visibility by both human observers, as well as cameras. In the recommendations, tall luminaire lighting replaces bollards, providing white light with a high color rendition index, and higher overall lighting level, conditions much more appropriate for surveillance.
For those interested in learning more about CPTED, a variety of resources are available.
- The National Crime Prevention Council [link no longer available] offers a number of presentations and guides free online.
- The International CPTED Association [link no longer available] provides some guides, including links to other resources, presentations from their past conferences, as well as CPTED Practitioner certifications.
- Crime Prevention Through Environmental Design, 2nd Edition outlines CPTED's history, possible strategies, and impact of CPTED on communities.