Crime Prevention - Crime Prevention Through Environmental Design - CPTED

Crime Prevention Through Environmental Design, also known as CPTED, is a multi-disciplinary approach to deterring criminal behavior through environmental design.

CPTED strategies rely upon the ability to influence offender decisions that precede criminal acts. Criminal behavior research shows that the decision to proceed or not proceed with a crimnal act is more influenced by indications to the apparent risk of being caught than by indications to reward or ease of entry. Consistent with this research, CPTED based strategies emphasize enhancing the perceived risk of detection and apprehension.

The CPTED strategies are Natural Surveillance, Natural Access Control, Territorial Reinforcement, and Maintenance.

Natural surveillance and access control strategies limit the opportunity for crime. Territorial reinforcement promotes social control through a variety of measures. Maintenance shows ownership of property. Deterioration of a property suggests less control by the owner or intended user of a property and indicates a greater acceptance of disorder.

Natural surveillance refers to areas where people and their activities can be readily observed. Natural surveillance can be obtained by designing landscapes that allow clear, unobstructed views of surrounding areas; improving visibility with proper lighting or transparent building materials; and avoiding the creation of building entrapment areas.

Examples of Natural Surveillance are:

• Design streets that increase pedestrian and bicycle traffic
• Locate windows on building that overlook sidewalks, parking lots, and other areas that would not be usually seen
• Leave window shades or blinds open
• Keep landscaping away from points of entry and opportunistic points of entry to give a clear line of sight
• When fencing an area, use a short, see through material for the situation
• When covering an entrance, use transparent materials
• When making a lighting design, avoid poorly placed lights that create blind-spots and shadowing for potential observers and miss critical areas. Entrance/exit areas, parking lots, refuse dumpsters, stairways and walkways, bus stops, children play areas should all be well lit
• Use full cut-off light fixtures and keep the lighting away from taller landscaping that may cause shadowing
• Use proper lighting on walkways or paths where a person can identify potential attackers

Natural Access Control refers to controlling access to a property. Natural access occurs when ensuring that entrances are visible, well lit and overlooked by windows.