To stop a terrorist or physical attack on a building is very difficult; any building or site can be breached or destroyed. However, the more secure the building or site is and the better the building is designed to withstand an attack, the greater the odds are that the building will not be attacked or, if attacked, will suffer less damage.
Terrorist select sites based on their value as a target. Some high-value targets would be iconic commercial properties, symbolic government buildings or structures likely to inflict significant emotional or economic damage. A common method to evaluate terrorist threats is to analyze five factors:
Knowing the expected threat or hazard capability allows us to integrate that knowledge with specific building and site information by conducting a vulnerability assessment.
A vulnerability assessment is an in-depth analysis of building weaknesses and lack of redundancy to determine mitigations or corrective actions that can be designed or implemented to reduce vulnerabilities. The extent and depth of the analysis will depend upon the size and function of the building and organization.
Some examples of recommended security measures based upon building/employee size are:
10 employees; 2,500 sq. ft.; low volume public contact
11-150 employees; 2,500-80,000 sq. ft; moderate volume public contact
151-450 employees; multi-story facility; 80,000-150,000 sq. ft.; moderate-to-high public contact
Target hardening includes security considerations that are routinely provided including perimeter fencing, site lighting, parking and drop-off design that supports access and security considerations and landscape design.
The building interior must also be included in target hardening plans. Consideration should be given to both interior and exterior gathering places. Public toilets should be in secured areas. Offices of essential officials should be placed so that the occupants cannot be seen from the street or public areas. Where possible the offices should face courtyards, internal sites and controlled areas. Windows should be glazed. Staff should be used for security observations.
Other areas warranting target hardening include: