21st Century Security and CPTED, 2nd Edition

193

13

Problem Seeking before

Problem Solving

Vulnerability Assessment*

ARE YOU FEELING VULNERABLE? BE AFRAID, BE VERY AFRAID

A vulnerability analysis is an in-depth analysis of the building functions, systems, and site characteristics

to identify the building weaknesses and need for protection. The goal is to determine proactive and

preventative actions to reduce the weaknesses to the expected threats or hazards. A vulnerability

analysis should be performed for the existing built environment, and the results and ndings integrated

into the design for new construction or renovation of buildings (FEMA 426, 2003, pp. 1–24).

The third step in the risk assessment process is to prepare a vulnerability assessment of the

assets that can be affected by a threat or a natural hazard (see Figure 13.1). Vulnerability is dened

as any weakness that can be exploited by an aggressor, or natural disaster event, to make an asset

susceptible to loss or damage. A vulnerability assessment is an in-depth analysis of the building

functions, systems, and site characteristics. The assessment identies building weaknesses and

the lack of redundancy that can increase potential damage resulting from man-made or natural

disasters. During this step, an analysis of the assets will begin based on:

• Identied threat/hazard

• Criticality of your assets

• Level of protection you have chosen (i.e., your willingness or unwillingness to accept risk)

*

Portions of the text in this chapter consist of articles and other publications previously written by the author including

possible portions found in the following Wiley publications: Architectural Graphics Standards, 10th edition, Ramsey/

Hoke, The American Institute of Architects, John Wiley & Sons, ISBN: 0471348163, 2000. Security Planning and

Design: A Guide for Architects and Building Design Professionals, J.A. Demkin, The American Institute of Architects,

John Wiley & Sons, ISBN: 0471271567, 2004. We offer special thanks to the American Institute of Architects and John

Wiley & Sons for permission to reproduce common content in this work.

CONTENTS

Are You Feeling Vulnerable? Be Afraid, Be Very Afraid ............................................................... 193

Identifying the Layers of Defense (Step 3: Task 3.1) .................................................................... 194

Understanding Redundancy Factors (Step 3: Task 3.2) ................................................................. 199

Cost Implications of Redundancy, Hardening, and Vulnerability ............................................. 200

Other Factors Affecting Vulnerabilities .....................................................................................200

Conducting the Site Inspection (Step 3: Task 3.3) ......................................................................... 201

Preparing a Vulnerability Portfolio (Step 3: Task 3.4) ................................................................... 201

Determining the Vulnerability Rating (Step 3: Task 3.5) ...............................................................202

Scale for Vulnerability Rating ................................................................................................... 202

What Kind of Factors Should Be Considered to Protect against Terrorism? .................................202

Summary ........................................................................................................................................204

References ......................................................................................................................................205

194 21st Century Security and CPTED

The vulnerability assessment process involves the following tasks:

• Understanding the layers of defense

• Understanding redundancy factors

• Conducting the site inspection

• Preparing a vulnerability portfolio

• Determining the vulnerability rating

IDENTIFYING THE LAYERS OF DEFENSE (STEP 3: TASK 3.1)

The layers of defense is a traditional approach to security design and CPTED, and uses concentric

circles extending out from the building or asset that requires protection into the site and surrounding

area. They can be seen as demarcation points for different security strategies. Identifying the layers

of defense early in the assessment process will help you to understand better the assets that require

protection and determine your mitigation options (see Figure 13.2).

First layer of defense: This involves understanding the characteristics of the surrounding area,

including construction type, occupancies, and the nature and intensity of adjacent activities. It is

specically concerned with buildings, installations, and infrastructure outside the site perimeter. It

is essential to understand the interdependencies and distance that separate your building and off-site

facilities. Off-site facilities can include:

• Landmarks and iconic buildings

• Law enforcement, re departments, and hospital buildings

• Federal facilities

• Embassies

• Key commercial properties

• HazMat storage areas and chemical manufacturing plants

• Transportation (roads, avenues of approach, bridges, railroads, tunnels, airports, and ports)

• Telecommunications and utility services

Step 1: Threat identification and rating

Step 2: Asset value assessment

Step 3: Vulnerability assessment

Tasks:

3.1 Understanding the layers

of defense

3.2 Understanding redundancy

factors

3.3 Conducting the site

inspection

3.4 Preparing a vulnerability

portfolio

3.5 Determining the

vulnerability rating

Step 4: Risk assessment

Step 5: Consider mitigation options

FIGURE 13.1 Understanding the layers of defense. (From FEMA 452, Risk Assessment: A How-to Guide

to Mitigate Potential Terrorist Attacks against Buildings, Buildings and Infrastructure Protection Series,

July2010.)