Screening vehicles and their contents at site entry points can help reduce the risk of explosive devices or weapons being brought onto sites.
The implementation of vehicle screening measures may also serve as a significant deterrent to those intending to bring in such items.
The organisation should use the operational requirement methodology to develop an understanding of its needs for measures for screening vehicles as part of its wider security regime. Vehicle screening should only be considered as a supplement for other risk reduction measures. Having rigorous controls on what vehicles and occupants are authorised to enter the site, for example by checking the drivers' and vehicles' credentials and turning away unexpected deliveries, may significantly reduce the risk.
Vehicle screening requirements
It is particularly important to be clear about the size and type of threats the organisation is concerned about, and the relative priority of these from a detection perspective. There are a wide range of threats which would require very different screening measures, for example:
- Vehicle-borne improvised explosive devices (VBIEDs) - large explosive devices necessitating a vehicle for delivery;
- Under-vehicle improvised explosive devices (UVIEDs) - small explosive devices specifically targeting the vehicle's driver or other occupants;
- Small, portable improvised explosive devices - where the vehicle is being used to transport the IED through the site's secure perimeter - such IEDs may be concealed within the vehicle, or within deliveries, personal bags, or other items contained within the vehicle.
- Firearms and ammunition - in small or large quantities.
- Other items such as those related to crime or protest materials.
The list of target items is likely to contain some which are considered essential to detect, some that it is desirable to detect, and other items that are of interest but failure to detect can be tolerated. Note that it is unlikely to be proportionate or cost effective to screen vehicles for smaller threats; a layered approach where vehicles are checked for large threats at the site perimeter, may be supplemented by screening of people and their belongings for smaller threats on entry to key buildings.
Consideration should be given to the different types of individuals driving vehicles entering the premises such as staff, visitors, couriers, contractors, or the public. It may be considered appropriate, given differing risk profiles, for some vehicles (for example visitors as opposed to staff), or different sized vehicles, to undergo different screening regimes. Assessment of the risk posed by different groups of vehicles is likely to vary with the extent to which they are known and their arrival is expected.
The risk associated with vehicles and the vulnerability of assets within a site perimeter will also depend on where vehicles can access and consideration of the layering of security measures will need to be factored into the risk assessment.
The operational requirement for the screening process will be informed by the risk assessment and should consider factors such as anticipated demand for the screening process (including how this may vary in time), space constraints and location (including consideration of possible queues), and integration with other security measures.
Methods for screening vehicles
For some applications a screening approach that is largely manual with simple visual inspection tools may be sufficient to meet the needs of the organisation, especially where demand is relatively low. Only where it has been established that technology will add real value to screening processes should its use be considered. Whilst use of technology can add significant value in certain scenarios it can be expensive to purchase, take up a large amount of space and may require considerable on-going investment for it to remain effective. Factors such as equipment maintenance and provision of on-going staff training should not be overlooked.
If it has been deemed appropriate to use technology to screen vehicles, the equipment employed must be carefully selected as there is a wide range of technologies available which can offer very different capabilities. It may be necessary to employ a combination of methods or technologies to cover the full range of vehicle types and threats to be detected. Any organisation planning to procure such screening solutions should satisfy itself, where necessary seeking independent expert advice, that the capability provided meets its operational needs.
With any screening approach that is adopted it is important to ensure that the process is specified and delivered in a way that addresses, and is proportionate to, the particular risks the site faces. All screening processes have limitations; these need to be properly understood, accepted, and if necessary mitigated against. Recommendations for screening vehicles given here should be seen as just one element of a wider security strategy.