Measure type: Target hardening
Target hardening is the measure of strengthening the security by increasing the required effort to commit crimes to or at an object.
- 1 Description
- 2 Examples
- 3 Effectiveness
- 4 Considerations
- 5 Footnotes and references
Target hardening involves all measures that make committing a crime more difficult and reduce the opportunities for criminals to achieve their goal. Dependent on the type of crime the realisation of this measure can take various forms, ranging from teaching self-defence to potential victims of assault to bomb-proofing buildings against terrorists. In general the aim of target hardening is not to make objects completely resistant to attack, but to increase the risk of an attack to a level where the risk outweighs the gain of the crime as perceived by the offender. For example, by increasing the time it takes to overcome the measures.
Examples of target hardening can be categorised by the type of attack they oppose:
Against forced entry
- Toughened glass (acrylic, polycarbon, etc.)
- Latticework or screens to cover windows
- Deadbolt and vertical-bolt locks and door anchor hinges with non-removable pins
- Metal door/window shutters
- Tamper-proof screws in fittings
- Bollards and indirect routes against ramming
- Vertical metal or small-mesh (unclimbable) fencing
- Steeply angled roofs with parapets and ridges
- Concrete or steel picnic tables, benches, bleachers
- Trash receptacles bolted to concrete bases
- Hardened rubber or plastic swing seats
- Fire-retardant paint
- High-impact plastic or steel fixtures
- Rough-play-tolerant adventure playgrounds
- Slash-proof and steel-framed seats
- Graffiti repellent spray on graffiti prone objects
- Tamper-proof sign hardware and fasteners
- Stand-off zones where no unauthorized access is possible
- Increasing bomb resistance for vulnerable (parts of) objects
- Locating vulnerable structures behind other, bomb-resistant or sacrificial structures
Against toxins and air-borne agents
- Closable air vents
- Filter systems
- Unreachable air intakes
- Alternative air intakes
- Emergency forced air circulation
- Separating traffic flows of for instance pedestrians and motor cycles to prevent snatch theft
Against all of the above
- Early warning (alarms, emergency button) of action force or action force present
- Quick response of action force (by for instance optimizing access from police station to area)
This measure can be effective to a range of security issues. These are:
|Financial gain||Boredom or compulsive behaviour||Impulse||Conflict in beliefs|
|Burglary||Physical assault||Destruction by riots||Mass killing|
|Ram-raiding||Sexual assault||Destruction of property by fanatics|
The realisation form of a measure should conform to the targeted public, threat level and surroundings: stand-off zones will be inappropriate in a shopping area and only deadbolted doors and windows are inappropriate for high-risk objects.
Urban planning considerations
Generally mechanisms for target hardening affect the scale of buildings and developments, as well as the micro-detailing of facades and streetscape furniture.
Urban planning techniques, such as land use analysis, can identify if vulnerabilities are present, and whether target hardening is an appropriate measure to consider in reducing the opportunity for criminal activity to occur. If taken into account during the development process, urban planning considerations can aid in the application of target hardening measures that compliment development goals instead of harming them. An example of this could be where the detailing design measures applied to hardening shop frontages are changed to replace external roller shutters (negative connotations and attractors of crime) with equally practical, yet more aesthetic options, such as strengthened security glass frontages, that engender a better atmosphere.
Target hardening measures aimed to improve security can have both positive and negative impacts on safety:
- Removing a door can harden a building against unauthorised entry, but can also reduce evacuation speed in case of emergencies such as fire
- Replacing normal glass by toughened glass increases resilience both against security threats such as burglars, and safety threats such as tornadoes.
It is important to consider that design features of target hardening influence citizens’ perception of being at risk. Excessive use of target hardening tactics, moreover, can create a 'fortress mentality' and imagery whereby residents withdraw behind physical barriers and the self-policing capacity of the built environment is damaged and has a negative influence on social resilience.
Some researchers have introduced a threefold grouping of physical features; prospect (for the user), refuge (for the potential offender) and escape (for the user and potential offender). For instance, research confirms that fear of crime is higher in locations that offer good refuge for the potential offender but low prospect and escape for the user. For social security, therefore, it is important that urban object are designed with clear lines of sight. For instance, for pedestrian and bicycle tunnels it is important to have, clear lines of sight, sufficient light, and decoration. This reduces the fear that a potential offender could be hiding somewhere. Pedestrian tunnels could be coupled to art projects, which make the environment a lot friendlier. This may reduce the feeling of insecurity.
The prospects for target hardening are not only physical in nature, also conduct and behavior are important in this context. This ranges from not leaving doors open, make sure that valuables are not visible from the outside, to not announcing that you are on vacation through social media such as Facebook and Twitter, your answering machine, voice mail or e-mail wizard.
Target hardening measures not only prevent material and immaterial damage for (potential) victims, but also prevent indirect economic damage to local and regional economies in terms of e.g. a decrease in house prices, the relocation of resources and the decrease of investments by private residents, businesses and public authorities. On top of that, these kind of measures have some positive externalities like reducing the fear of crime and the possible reduction of the use of energy (for instance in case of burglary proof windows), see the case example below.
Target hardening measures, however, do require time and financial means by private agents, companies/developers and the public authorities. These cost contain the relatively straightforward direct expenditures on capital equipment and operational cost (both temporary and permanent), and in addition generate various types of indirect economic effects. Target hardening measures like big concrete walls or window bars in retail areas, for example, are measures that could create an unwelcome environment. This, in turn, could result in a reduced perceived security and environmental quality, generating negative indirect economic effects very similar to the indirect economic effects of frequently occurring property and violent crimes like burglary and vandalism. Hence, from an economic point of view, more subtle variations of target hardening measures like sustainable design measures that combine energy efficiency with security and qualitative design, would be better security options.
Whether the cost of any particular target hardening measures are making sense from an economic point of view, depends on many factors, and can be answered by two distinct sets of questions (see also the flow chart of an economic assessment):
- Are the envisioned target hardening measures cost effective from a socioeconomic point of view, or are there better alternatives?
- Which specific agents (individuals, companies, sectors, authorities) are affected by the target hardening measures, and to which extend? How do the envisioned measures alter the behaviour of these agents, and, of course, the behaviour of criminals/terrorists (in economic terms)?
Case example: A cost-benefit analysis of safer homes:
The Association of British Insurers (ABI) performed a cost-benefit analysis on target hardening measures for home security. The analysis was based on the estimates of the average household cost of burglary (£3,300), the average cost of Security By Design (SBD) target hardening (£630), burglary rates (average 2.7% - 6.7% range), and socio-economic demographics. The per household net present value benefit of target hardening measures was projected over 20 years, yielding benefits of over £1,170 per household. As a result, the average household benefits are nearly double the average cost of the introduced security measures.
The case example above illustrates why it is important to research the positive and negative economic effects of a particular security measure.Economic tools can help decision makers to answer these questions and to prevent wasteful expenditures on security (of course in collaboration with insights from criminology, sociology, etc.).
Some target hardening measures work by limiting the mobility or accessibility to a certain location or area, for example by obstacles such as bollards, barriers or low speed roads with narrows. Though this helps to prevent certain crimes, it has a negative effect on the accessibility in general.
The other way around, in some cases it may help to increase accessibility in order to ensure that emergency services can reach an incident location as quickly as possible (see also incident mangement).
Routes between certain nodes are particularly vulnerable to crime, for example- homes that are on the route from a large bar may be vulnerable to vandalism and other types of minor disorder as well as to burglary. Planners can use this knowledge to help prevent crime when designing roads and accessibility routes in new communities.
Target hardening requires selection of targets that are worth hardening. This involves ethics issues because limited resources will probably not allow addressing all relevant targets. This may lead to the creation of different levels of security in society. This illustrates the need to provide norms and standards beyond frameworks for built infrastructure.
Investigating human and societal needs regarding target hardening should be a priority. To support this, VITRUV offers a commented list of methods to determine ethics aspects in relevant urban planning.
Legal considerations when considering target hardening measures are:
- Appearance - Target hardening may change the appearance of an object
- Development management standards - Target hardening may conflict with planning standards like construction height, sustainability, etc.
- Safety - Hardening an object might make it more secure, but less safe
- Building codes / building regulations - Changes due to target hardening may conflict with building standards
- Cultural heritage preservation - Target hardening changes may impose on cultural heritage rules
Footnotes and references
- To assess the enhancement of these measures the Detail level tool can be used.
- Royal Borough of Kensington and Chelsea, Designing Out Crime, 2008, http://www.rbkc.gov.uk/pdf/designingoutcrime_spd.pdf
- e.g., Fisher and Nasar, 1992
- Association of British Insurers (2006): Securing the Nation: The Case for Safer Homes.