BUILDING DESIGN FOR HOMELAND SECURITY

Unit III
Threat/Hazard
Assessment

Unit Objectives

Identify the threats and hazards 
that may impact a building or 
site. 
Define each threat and hazard 
using the FEMA 426 
methodology. 
Provide a numerical rating for the 
threat or hazard and justify the basis 
for the rating. 
Define the Design Basis Threat, Levels 
of Protection, and Layers of Defense. 
Assessment Flow 
Chart

Nature of the Threat

From Patterns of Global Terrorism Ð 2001 Released by the Office of the 
Coordinator for 
Counterterrorism, May 21, 2002 
BUILDING DESIGN FOR HOMELAND SECURITY Unit III-4

Nature of
the Threat

Hazard

Hazard -A source of potential 
danger or adverse condition. 
¥	Natural Hazards are naturally-
occurring events such as floods, 
earthquakes, tornadoes, tsunami, 
coastal storms, landslides, 
hurricanes, and wildfires. 
Manmade 
Threats/Hazards

Manmade Hazards Ð are technological 
accidents and terrorist attacks. These 
are distinct from natural hazards 
primarily in that they originate from 
human activity. 
Terrorism act 
BUILDING DESIGN FOR HOMELAND SECURITY Unit III-8 
Identify Each 
Threat/Hazard

Agri-terrorism 
Improvised Explosive 
Radiological Agent 
Device (Bomb) 
Nuclear Device 
Chemical Agent 
Hazardous Materials 
Arson/Incendiary Attack 
Release 
Biological Agent 
Unauthorized Entry 
Cyberterrorism 
Surveillance 


Determine Threat Level 
for Each Hazard 
BUILDING DESIGN FOR HOMELAND SECURITY Unit III-11 
Threat Sources

Identify Threat Statements
Identify Area Threats
Identify Facility-Specific Threats
Identify Potential Threat

Element Attributes 
Reference: Page 1-15, FEMA 426 
BUILDING DESIGN FOR HOMELAND SECURITY Unit III-12 
Critical Functions

Function 
Cyber attack 
Armed attack 
(single gunman) 
Vehicle 
bomb 
CBR attack 
Administration 




Asset Value 
5 
5 
5 
5 
Threat Rating 
8 
4 
3 
2 
Vulnerability Rating 




Engineering 




Asset Value 
8 
8 
8 
8 
Threat Rating 
8 
5 
6 
2 
Vulnerability Rating 





Critical Infrastructure

Function 
Cyber attack 
Armed attack 
(single gunman) 
Vehicle 
bomb 
CBR attack 
Site 




Asset Value 
4 
4 
4 
4 
Threat Rating 
4 
4 
3 
2 
Vulnerability Rating 




Structural Systems 




Asset Value 
8 
8 
8 
8 
Threat Rating 
3 
4 
3 
2 
Vulnerability Rating 





Design Basis Threat

The threat against which assets within a 
building must be
protected and upon which the security 
engineering design

Level of Protection (1)

Layers of Defense Elements

. _ Deter 
. _ Detect 
. _ Deny 

¥ Devalue
The strategy of Layers of Defense
uses the elements and Levels of
Protection to develop mitigation
options to counter or defeat the

tactics, weapons, and effects of
an attack defined by the Design

Levels of
Protection (2)

Table 1-6, page 1-26, FEMA 426 
Levels of Protection (3)

DoD Minimum
Antiterrorism (AT)
Standards for New
Buildings

Table 4-1, page 4-9 
Level of Protection (4)

Level of Protection (5)

UFC 4-010-01 APPENDIX B DoD MINIMUM ANTITERRORISM STANDARDS FOR NEW AND 
EXISTING BUILDINGS 
Standard 13 
Mailrooms 
Standard 14 
Roof Access 
Standard 15 
Overhead Mounted Architectural Features 
Standard 16 
Air Intakes 
Standard 17 
Mailroom Ventilation 
Standard 18 
Emergency Air Distribution Shutoff 
Standard 19 
Utility Distribution and Installation 
Standard 20 
Equipment Bracing 
Standard 21 
Under Building Access 
Standard 22 
Mass Notification 

Summary

Process 
. ¥ Identify each threat/hazard 
. ¥ Define each threat/hazard 
. ¥ Determine threat level for each 
threat/hazard 

Threat Assessment Specialist Tasks 
Critical Infrastructure and Critical 
Function Matrix Determine the "Design 
Basis Threat" 
Unit III Case Study 
Activity

Asset Value Ratings 
Background 
Hazards categories: natural and manmade 
HIC case study threat: explosive blast and 
chemical, biological, and/or radiological agents 
Result of assessment: "Threat Rating," a 
subjective judgment of a threat 
Requirements

Refer to HIC case study data and GIS 
portfolio
Complete worksheet tables:

¥	HIC Critical Functions Threat Rating
HIC Infrastructure Threat Rating

BUILDING 
DESIGN FOR 
HOMELAND 
SECURITY Unit 
III-22