Crime prevention through environmental design alters the internal and/or external environment of a facility to increase crime deterrence and the likelihood of apprehension and detection of criminals. Landscape planners, architects, developers and security professionals use CPTED to secure built structures and to improve the image of the individuals or companies that own them. And, as the National Crime Prevention Institute says, “The proper design and effective use of the built environment can lead to a reduction in the fear of crime and incidence of crime, and to an improvement in quality of life.”
The Origin of CPTED
Architect Oscar Newman developed the initial and most recognized documentation of CPTED in 1972 in his book Defensible Space. The core components of the design strategy allow for a balanced security presence by taking into account physical security—in this case referring to architectural components like doors, walls, fencing and landscaping—technical security, which includes alarms, access control technologies and CCTV, and operational security—that is, the policies and procedures that govern the security program.
CPTED uses these components of balanced security to create a built environment that facilitates the deterrence and delay of criminals and increases the likelihood of detection of criminal activities. Here we'll explore a few examples of CPTED strategies security directors should keep in mind if they're participating in new structure design.
Strategies for Physical Security
Compartmentalization. Compartmentalization means designing the facility to include layers of security starting from the outer perimeter and moving inward to the highest-security area of the building.
Natural Surveillance. Natural surveillance includes the placement of windows, open areas and clear lines of sight to minimize built-in hiding places for criminals. It can be complemented by CCTV, but not replaced by it. Natural surveillance should also provide adequate clear space between the access points to the property and the actual exterior of the facility. Properly designed, clear sight lines will prevent potential ambush and hiding areas and should extend beyond the building's façade.
Activity Support. In the movies, the hero often tells the villain that he will meet him in a public space, anticipating that the villain won't pull any tricks in a highly visible area. The hero is using the concept of activity support to enhance the concept of natural surveillance. It is easy to establish public venues to support and enhance security. These will become part of the natural surveillance system, which will deter criminal activity.
If you know of areas that could provide cover for ambush, place vending machines, telephones and other public interest points nearby. An ambush will be less likely in an area that is well traveled by multiple potential witnesses.
Territorial Enforcement. Territorial enforcement relates to the natural progression from public to private space. Clearly defining the boundaries between public and private areas of the campus or building through landscaping, architecture and technology establishes a sense of ownership and pride and sends a message that the private area is off limits. This pride or psychological ownership is also perceived by visitors and pedestrian traffic. Therefore, territorial enforcement is likely to encourage increased subliminal perception of an area as secured or inaccessible.
Territorial enforcement can also be used to direct pedestrian and vehicle traffic and can define where the property begins, sending a clear message to visitors, tenants and staff.
For instance, most buildings are directly accessible from driveways or roads. In some cases, those roads are straight. This could allow a vehicle to approach the facility at a high rate of speed, providing the opportunity for deliberate or accidental vehicular ramming. The costs to provide supplementary vehicle arresting equipment to offset this threat in a real-world application could be in the hundreds of thousands of dollars. Using the strategies of CPTED, however, you could instead design a winding road that provides areas for landscaping and natural access control, thereby preventing the opportunity for a high-speed vehicular ram attack.