Stage 3: Appraising and Mitigating Impacts: Safety and security impacts
The two main areas of safety impacts that should be assessed are:
- the risk of traffic related collisions for those using and passing by the site, and
- feelings of insecurity for those using and passing by the site.
Changes in the risk of collisions result from changes to the level and mix of traffic, the layout of footways, cycle-ways and roadways, and accesses to roadways. These can be appraised before the introduction of the development by means of a safety audit.
The most direct indicator of safety is the number of recorded collisions. For larger developments it may be possible to predict likely impacts on the number of collisions based on data relating to collisions on different types of road, and junction designs.
For most smaller developments this is not suitable, nor does it cover all aspects of safety relating to collisions. In these situations it is necessary to look for design factors, which are likely to lead to conflict between different users.
A range of design and social factors determines perceptions of risk and personal security depending on the characteristics of areas that pedestrians use. Design factors include:
- characteristics of site perimeters (such as whether solid walls are used, and the design features of entrances and exits);
- surveillance systems (such as CCTV, and staff with the role of surveillance);
- informal surveillance (relating to visibility lines from busy areas);
- landscaping (relating to visibility, and 'cover' for intruders);
- lighting and visibility (such as placement of pillars, recesses, and quality of lighting),
- the provision of emergency call facilities;
- how busy the area feels: a greater presence of people leads to greater feelings of security; and
- good sight lines, and a lack of ‘dead ends’.