Introduction to CPTED Crime prevention through spatial design.

Introduction to CPTED Crime prevention through spatial design.

CPTED (Crime Prevention Through Environmental Design) is an increasingly popular method for preventing crime and offending. As a proven theory, it brings a new vision to the design of security perimeters and the securing of areas in the broadest sense. Let’s take a look at a model that is all too often sidelined when it comes to security.

What is the CPTED?

In fact, the name says it all: CPTED encompasses all research on the environment dedicated to crime prevention. This means that any act of analysis, prevention or reduction of the risks associated with crime, and which uses the modification of an environment, is taken into account by CPTED. The use of the term environment is deliberate, as the CPTED approach can be applied to homes, industrial infrastructures and public areas.

The basic concept is to use the physical environment to prevent intrusion, theft or destruction of equipment as far as possible. To achieve this, there are two points that absolutely must be taken into account. The first is to include a strategy based on crime studies when constructing a building. Secondly, once the building or area has been constructed, it must be used correctly, in accordance with CPTED recommendations.

There are many advantages to pursuing a CPTED strategy. Firstly, the buildings will be used more efficiently, both in terms of safety and maintenance. In addition, users’ feeling of insecurity will be reduced. This is thanks to a design that reduces the dangers associated with crime.

Finally, by implementing a number of simple rules, we can put a stop to many attempted criminal acts. Reducing crime in space is the main mission of environmental design for defence.

The fundamentals of CPTED are very popular at the moment. In the face of insecurity and the desire to design a new vision of defence. Introduced in crime prevention reports, environmental design is a serious issue for the authorities in charge of defending a territory. All the more so as it has the advantage of bringing both short and long-term benefits. However, it is only one more tool in the fight against crime, and prevention through environmental design can never prevent the whole issue of defence and crime.

Please note that although CPTED is of prime importance, building construction and safety standards take precedence and must be respected. No CPTED approach should conflict with the prerogatives in terms of construction standards applicable in a given country. For example, the systems put in place must validate evacuation systems in the event of danger (fire, gas, etc.), even if they may be considered as exploitable loopholes for criminals.

Now that we’ve seen what an innovative and effective approach CPTED is to securing an environment, let’s get down to business by analysing the key principles of the method.

The key principles of environmental design.

Ultimately, environmental design can be divided into four main stages or pillars that must be respected to achieve a satisfactory overall result:

Natural supervision.

This concept is based on the community interacting within the zone in order to set up an initial investigation of the premises. The aim of this section is to encourage users to keep a neutral but vigilant eye on intruders entering the zone. In the case of a no-entry perimeter, this surveillance can be extended to the immediate environment.

To ensure vigilance at all times, visibility in the area must be increased. This can be done by stretching out spaces as much as possible or by increasing lighting levels, particularly at night. Finally, it may also be worthwhile increasing the number of agents likely to report strange behaviour.

Natural access control.

To reduce the risk of intruders, the first thing to do is to add boundaries to limit access as much as possible. This includes installing gates and locks, as well as natural elements such as shrubs and hedges.

Another key concept in this section is the centralisation of communal areas, which are vulnerable to attack. Where this is not possible, incorporating them into major communication routes is also a good idea.

Strengthening the territory.

Once the surveillance and demarcations are in place, we can focus on reinforcing the zone. For example, by highlighting the distinction between public and private spaces. Or by dividing the zone into self-managed units, as in a residential area, for example.

Maintenance.

In order to guarantee the proper use and longevity of the solutions implemented above, it is necessary to guarantee the care and maintenance of the area. The maintenance process is designed to protect the health and safety of the staff, as well as their well-being. This is a meticulous job, because if you want to maintain one of these aspects, you may have an impact on another.

Despite the particular attention paid to these four areas, environmental design does not claim to have a turnkey solution for every archetypal site. The correct use of CPTED principles is the result of a meticulous analysis of the site and the actions that can be envisaged in the short and medium term.

In other words, after the efforts made to comply with the CPTED recommendations, we can expect reasonable results. It is not possible to take into account all the factors that predestine a criminal act. Especially as the approach is transdisciplinary and requires a great deal of experience in the field. You can’t expect to understand everything from the outset, but you do need to master the whole strategy.

Finally, increased knowledge of your environment and of potential dangers will be the best asset for achieving maximum success.

CPTED technique and approach.

How to manage risks with CPTED.

There are three approaches that we can combine in order to implement reasonable risk management in an environment.

The Natural approach.

The Natural approach is based on the influence that can be brought to bear on users and their uses. This can come from the design of buildings and/or housing, reinforcing users’ sense of responsibility. In this way, we guarantee an increase in vigilance and defence of a place in the event of minor problems.

An effective tool for facilitating the appropriation and maintenance of a place is the creation of a community environment. This considerably reduces crime internally and strengthens surveillance with external exchanges. Several methods are available to achieve this:

  • Incorporating physical or symbolic barriers to delimit an area.
  • Increase contact between users as much as possible.
  • Increasing users’ field of vision with appropriate lighting and site design.
  • Concentrate on major, densely populated flows and high-risk areas.

It is important to take into account the surveillance aspect as a factor in the fight against crime. Not imposing digital surveillance and preferring a community-based approach is a good way of getting officers to endorse the concept. Remember that the welfare aspect is just as important in the CPTED approach.

The formal approach.

This is the approach most often used in companies, since it allows for greater customisation and can be adapted to more specific cases. It encompasses all techniques involving an organisational process (protocol, level of access, etc.) and the introduction of security services.

The Mechanical approach.

Often likened to a hardening of the existing model, the mechanical approach consists of integrating tools and equipment into the area to make it more secure. The underlying objective is to increase security by obstructing access and surveillance.

This can be achieved by adding a stronger lock or a more complex system (magnetic lock, biometric lock, etc.), but also by installing surveillance cameras in strategic areas.

The mechanical approach will generally be used to prevent specific instances of crime in particular, restricted locations within the area. It is an effective method of closing certain gaps in environmental design when they are detected after the overall strategy has been created.

However, this is not without its drawbacks. Integrating a made-to-measure strategy will obviously entail costs and maintenance requirements. There are also risks in terms of acceptance of the system by users in the area. What’s more, this type of system does not protect against professional criminals who know how to foil most systems. Even if the ratio of attempts decreases with the complexity of the system put in place.

We have a number of tools at our disposal to reap the benefits of an environmental design approach. Let’s look in more detail at two major points that are essential for crime prevention, and which CPTED is following closely.

Human behaviour is the cornerstone of the CPTED approach.

For a while, the environment was poorly taken into account by those involved in crime prevention. Mistakenly regarded as a stable parameter with no impact, we have forgotten its role in human psychological behaviour.

In fact, research has shown a causal relationship between the environmental context and human behaviour. Here is a list of the immediate relationships between behaviour and the environment:

Structural change in an environment will cause a tendency or behaviour to disappear, moving over time to a more favourable environment. This creates migratory flows between different environments. This is true both macroscopically (countries, continents, etc.) and microscopically (companies, residential areas, etc.).

Human behaviour varies according to a number of environmental criteria. The physical environment obviously has an impact on behaviour, but so does the social, economic and political environment…

Changes in the environment will have an impact not only on the general behaviour of players, but also on other aspects of the environment. An economic change will have repercussions on the social aspect and vice versa.

Obviously, the concepts mentioned are not common to all circumstances. Nevertheless, they have been tried and tested empirically. As a general rule, the more complex the environment, the more difficult it is to identify the links between the environment and behaviour.

In order to be able to manipulate the environment in the right way, environmental design is based on minor variations in space, so that behaviour can be varied at the margin. It’s an effective method for verifying the causality of actions taken.

Opportunities left to criminals.

The majority of acts of vandalism and crime are the result of opportunities given to attackers to carry out their misdeeds. For example, the general trend has shown that buildings and lifts are high-risk areas because they restrict escape and the presence of the public. Shops at the end of shopping areas are also frequent targets of vandalism compared with centralised establishments. Finally, isolated areas in sparsely populated neighbourhoods, such as second homes, are prime targets for burglars.

To avoid inconvenience, you need to guard against the risks, analyse the type of environment in question and educate yourself about potential crime. The actions to be taken to limit assaults will not be the same as those to limit burglaries. It is the responsibility of both the designer and the owner of an establishment to work on the risks before incorporating a defence model.

We have seen that criminal behaviour is the result of a given opportunity. In fact, it is important to think of the criminal as a professional. He acts simply under the apprehension of a risk analysis. Depending on their estimated success rate, they may or may not act. Basically, what matters is the visibility of the area, its defence and the ability to flee in the event of a problem.

Finally, the fewer opportunities the area offers, the lower the trial and success rate will be. Other factors come into play when estimating the success rate, such as the number of potential victims. Lastly, many opportunities are lost through inaction on the part of users or through action that is unfavourable to crime prevention. Neglect of the CPTED’s maintenance section is one of the main dangers to the sustainability of a venue.

Risks to be taken into account in implementation.

There are certain risks involved in creating a strategy based on CPTED that you need to guard against. In a way, it’s advice that needs to be followed.

1- Talk to the designer rather than the owner about prevention.

Indeed, if the strategy is implemented when the venue is built. It is essential that the designers of the venue are made aware of the importance of environmental design.

The site owner will be more interested in the safety benefits for the area. But it is the designers who should be targeted when it comes to the techniques to be implemented to ensure proper compliance with environmental design.

2- Too much negligence on the part of users.

Une bonne partie de la stratégie de conception environnementale dépend de l’action des usagers dans le milieu. Si une atmosphère collaborative n’arrive pas à être instaurée au sein de la zone, les retombés en termes de sécurité seront moindre.

You need to ensure that there is good communication about the processes put in place and the role of each player within the overall strategy. Otherwise, the work carried out will be unacceptable.

3 – Bad building management.

As we have seen, maintenance is one of the pillars of CPTED. If the management of the area is neglected, the results tend to decline little by little.

It is important to take the necessary steps to ensure that the buildings and structures in the area to be protected are put to good use and remain in good condition.

We have seen a modern approach to crime prevention with environmental design. This method is still in its infancy, and despite studies providing a positive vision of the approach, a number of unknowns remain. It is likely that the advice given will change in the future, and that others will be added to the approach. Nevertheless, the CPTED does not require a great deal of cost in the overall safety strategy. As a result, it would be a pity not to use it as a basis for improving the safety of a site.

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Maxime Macé

Simple passionné de thématiques diverses et variées. J’apprécie enrichir mes connaissances dans les disciplines techniques comme l’informatique, les sciences et l’ingénierie, mais aussi dans les domaines merveilleux de la philosophie, l’art et la littérature.

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