FEMA 426 / December 2003

Risk Management Series
Reference Manual 
to Mitigate Potential Terrorist Attacks Against 
Buildings
December 2003

FEM


RISK MANAGEMENT SERIES

Reference Manual to 
Mitigate Potential 
Terrorist
Attacks Against Buildings
PROVIDING PROTECTION TO PEOPLE AND BUILDING


www.fema.go


Any opinions, findings, conclusions, or recommendations expressed in this 
publication do not necessarily reflect the views of FEMA. Additionally, neither FEMA 
or any of its employees makes any warrantee, expressed or implied, or assumes any 
legal liability or responsibility for the accuracy, completeness, or usefulness of any 
information, product, or process included in this publication. Users of information 
from this publication assume all liability arising from such use




The creation of the Department of Homeland Security (DHS) is one of the most 
significant transformations in the Federal Government in decades, establishing a 
department whose first priority is to protect the nation against terrorist attacks. 
Within the DHS, the Directorate of Emergency Preparedness and Response (EP&R) is 
focused on ensuring that our nation is prepared for catastrophes, including both 
natural disasters and terrorist assaults.
Central to this mission is the protection of people and the critical infrastructure of 
the built environment. This Reference Manual to Mitigate Potential Terrorist Attacks 
Against Buildings provides guidance to the building science community of architects 
and engineers, to reduce physical damage to buildings, related infrastructure, and 
people caused by terrorist assaults.  
The comprehensive approach to understanding how to improve security in high 
occupancy buildings will better protect the nation from potential threats by 
identifying key actions and design criteria to strengthen our buildings from the 
forces that might be anticipated in a terrorist assault. It is important to note that 
many of the methodologies in this publication have been adapted from other 
government sources and modified to meet the mission of the DHS. This allows for 
the effective transfer of decades of federal and Department of Defense research and 
experience to the broader building science community.
This document was prepared by the Building Sciences and Technology Branch of the 
Mitigation Division, part of EP&R. The DHS would like to thank the following 
agencies for their contribution and input to this publication:
_	General Services Administration
_	Naval Facilities Engineering Service Center
_	Naval Facilities Command (NAVFAC) Criteria Office
_	USACE Protective Design Center
_	Department of Veterans Affairs
_	Centers for Disease Control and Prevention/National Institute for 
Occupational Safety and Health
_	Department of Justice, Office of Domestic Preparedness (DHS - Border and 
Transportation Security)
_	United States Air Force - Civil Engineer Support Agency


Michael D. Brown
Under Secretary
Emergency Preparedness
and Response Directorate
Anthony S. Lowe
Director
Mitigation Division
Emergency Preparedness and Response Directorate




FOREWORD AND ACKNOWLEDGMENT


BACKGROUND
The Federal Emergency Management Agency (FEMA) developed this Reference Manual 
to Mitigate Potential Terrorist Attacks Against Buildings to provide needed information on 
how to mitigate the effects of potential terrorist attacks. The intended audience in-
cludes the building sciences community of architects and engineers working for 
private institutions, and state and local government ofcials working in the building 
sciences community. The manual supports FEMAs Mission (Lead America to 
prepare for, prevent, respond to, and recover from disasters) and the Strategic Plans 
Goal 3 (Prepare the Nation to address the consequences of terrorism), all of which 
will be done within the all-hazards framework and the needs of Homeland Security.
The building science community, as a result of FEMAs efforts, has incorporated 
extensive building science into designing and constructing buildings against natural 
hazards (earthquake, re, ood, and wind). To date, the same level of understanding 
has not been applied to manmade hazards (terrorism/intentional acts) and tech-
nological hazards (accidental events). Since September 11, 2001, terrorism has 
become a dominant domestic concern. Security can no longer be viewed as a 
standalone capability that can be purchased as an afterthought and then put in place. 
Life, safety, and security issues must become a design goal from the beginning. 
OBJECTIVE AND SCOPE 
The objective of this manual is to reduce physical damage to structural and non-
structural components of buildings and related infrastructure, and also to reduce 
resultant casualties during conventional bomb attacks, as well as attacks using 
chemical, biological, and radiological (CBR) agents. Although the process is general 
in nature and applies to most building uses, this manual is most applicable for six 
specic types of facilities:
_   Commercial ofce facilities
_   Retail commercial facilities
_   Light industrial and manufacturing facilities
_   Health care facilities
_   Local schools (K-12), and
_   Higher education (university) facilities
The processes and measures may not generally be economical or applicable to lighter 
density occupancies, such as single-family homes. More intense occupancies (e.g., 
industrial facilities) have already been addressed in most cases.
This is one of a series of publications that address security issues in high-population, 
private sector buildings. This document is the foundation of the Building Vulnerability 
Design Against Terrorist Attacks Training Course (FEMA 438).
The purpose of this manual is to provide guidance to the building sciences 
community working for private institutions. It presents tools to help decision-makers 
assess the performance of their buildings against terrorist threats and to rank 
recommendations. It is up to the decision-makers to decide which types of threats 
they wish to protect against and to determine their level of risk to each threat. Those 
decision-makers who consider their buildings to be at high risk can use this 
guidance as necessary.
The information contained in this document is:
_  not mandatory
_  not applicable to all buildings
_  not applicable when it interferes with other hazards such as re
This manual presents incremental approaches that can be implemented over time to 
decrease the vulnerability of buildings to terrorist threats. Many of the 
recommendations can be implemented quickly and cost-effectively.
ASSUMPTIONS
The information provided herein builds upon the synergies between the mitigation 
measures for natural hazards and manmade hazards. For example, seismic standards 
for non-structural building components are benecial against the explosive blast of 
conventional bombs. Hurricane window design, especially against ying debris, 
applies also to explosive blast. Landscaping for mitigation against wildres improves 
detection of placed devices. Ventilation system design against airborne biological, 
chemical, and radiological agents also works for similar hazardous material releases, 
whether intentional or accidental. Assessing threat, vulnerability, and risk may be 
complicated when comparing natural against manmade hazards. A natural hazard 
refers to a natural event such as a ood, wind, or seismic disaster. Historical data have 
been used by FEMA and other agencies/organizations to economically quantify the 
risk for natural hazards. Manmade hazards include technological hazards and 
terrorism and they are distinct from natural hazards primarily in that they originate 
from human activity. Technological hazards are assumed to be accidental and that 
their consequences are unintended. There is limited discussion of technological 
hazards in this document. For manmade hazards, the threat and likelihood of 
occurrence are less well dened and the associated vulnerabilities have many con-
siderations that impact making good risk management decisions.
ORGANIZATION AND CONTENT OF THE MANUAL
This manual contains many how-to aspects based upon current information 
contained in FEMA, Department of Commerce, Department of Defense (including 
Army, Navy, and Air Force), Department of Justice, General Services Administration, 
Department of Veterans Affairs, Centers for Disease Control and Prevention/National 
Institute for Occupational Safety and Health, and other publications. It is intended to 
provide an understanding of the current methodologies for assessing threat/hazard, 
vulnerability, and risk, and the design considerations needed to improve protection 
of new and existing buildings and the people occupying them. As needed, this 
manual should be supplemented with more extensive technical resources, as well as 
the use of experts when necessary.
_  Chapter 1 presents selected methodologies to integrate threat/hazard, asset value, 
and vulnerability assessment information. This information becomes the input 
for determining relative levels of risk. Higher risk hazards require mitigation 
measures to reduce risk. The chapter also provides an assessment checklist that 
compiles many best practices (based upon current technologies and scientic 
research) to consider during the design of a new building or renovation of an 
existing building. The checklist can also be used to assess the vulnerability of 
existing buildings within the context of the dened threats.
_  Chapter 2 discusses architectural and engineering design considerations 
(mitigation measures), starting at the perimeter of the property line, and includes 
the orientation of the building on the site. Therefore, this chapter covers issues 
outside the building envelope.  
_  Chapter 3 provides the same considerations for the building  its envelope, systems, 
and interior layout. 
_  Chapter 4 provides a discussion of blast theory to understand the dynamics of the 
blast pressure wave, the response of building components, and a consistent 
approach to dene levels of protection.
_  Chapter 5 presents CBR measures that can be taken to mitigate vulnerabilities and 
reduce associated risks for these terrorist tactics or technological hazards.
_  Appendices A, B, and C contain acronyms, general denitions, and CBR 
denitions, respectively.  
_  Appendix D describes electronic security systems and design considerations. 
_  Appendices E and F present a comprehensive bibliography of publications, and the 
associations and organizations capturing the building security guidance needed 
by the building sciences community, respectively.
ACKNOWLEDGMENTS
Principal Authors:
Michael Chipley, UTD, Inc.
Michael Kaminskas, UTD, Inc.
Wesley Lyon, UTD, Inc.
David Beshlin, UTD, Inc.
Mark Hester, UTD, Inc.
Contributors:
Milagros Kennett, FEMA, Project Ofcer, Risk Management Series Publications
Eric Letvin, Greenhorne & OMara, Inc., Consultant 
Project Manager
Eve Hinman, ATC/Hinman Consulting Engineers, Inc.
G. Scott Earnest, CDC/NIOSH
Michael Gressel, CDC/NIOSH
Kenneth Mead, CDC/NIOSH
D. Shawn Fenn, FEMA
Randall Hoffman, UTD, Inc.
Damian Kolbay, UTD, Inc.
Mark Hankewycz, Gage-Babcock, Inc.
Christopher Arnold, Building Systems Development, Inc.
Deb Daly, Greenhorne & OMara, Inc.
Wanda Rizer, Greenhorne & OMara, Inc.
Julie Liptak, Greenhorne & OMara, Inc.
Bob Pendley, Greenhorne & OMara, Inc.
Bill Modzeleski, Department of Education
Project Advisory Panel:
Wade Belcher, General Services Administration
Curt Betts, U.S. Army Corps of Engineers
Jim Caulder, U.S. Air Force  Civil Engineer Support Agency
Marcelle Habibion, Department of Veterans Affairs
Joseph Hartman, U.S. Army Corps of Engineers
David Hattis, Building TechnoIogy, Inc.
Rick Jones, Naval Facilities Engineering Service Center
Kurt Knight, Department of Veterans Affairs
Frederick Krimgold, Virginia Tech
John Lynch, Naval Facilities Command (NAVFAC) Criteria Ofce
Terry Pruitt, Department of Homeland Security
Chris Rojahn, Applied Technology Council
Lloyd Siegel, Department of Veterans Affairs
William Whiddon, Building Technology, Inc. 
This manual was prepared under contract to FEMA. It will be revised periodically, and 
comments and feedback to improve future editions are welcome. Please send 
comments and feedback by e-mail to riskmanagementseriespubs@dhs.go 




TABLE OF CONTENT



FOREWORD AND ACKNOWLEDGMENTSi
Backgroundi
Objective and Scopei
Assumptionsiii
Organization and Content of the Manualiii
Acknowledgmentsv
CHAPTER 1  ASSET VALUE, THREAT/HAZARD, VULNERABILITY, AND RISK1-
1
1.1  Asset Value Assessment1-10
1.1.1  Identifying Building Core Functions1-11
1.1.2  Identifying Building Infrastructure1-11
1.1.3  Quantifying Asset Value1-12
1.2 Threat/Hazard Assessment1-14
1.2.1  Threat/Hazard Identification1-14
1.2.2  Threat Definition of Physical Attack  on a Building1-21
1.3 Vulnerability Assessment1-24
1.4  Risk Assessment1-35
1.5  Risk Management1-42
1.6  Building Vulnerabilty Assessment Checklist 1-45
CHAPTER 2  SITE AND LAYOUT DESIGN GUIDANCE2-1
2.1  Land Use Considerations2-2
2.2  Site Planning2-6
2.2.1  Site Design2-6
2.2.2  Layout and Form2-6
2.2.3  Vehicular and Pedestrian Circulation2-11
2.2.4  Infrastructures and Lifelines2-13
2.2.5  Landscape and Urban Design2-14
2.3  Stand-off Distance2-22
2.4  Controlled Access Zones2-25
2.4.1  Physical Protective Barriers2-27
2.4.2  Other Perimeter Barriers2-30
2.4.3  Anti-ram Vehicle Barriers2-32
2.5  Entry Control and Vehicular Access2-36
2.6  Signage2-40
2.7  Parking2-42
2.8  Loading Docks and Service Access2-44
2.9  Physical Security Lighting2-45
2.10  Site Utilities2-47
2.11  Summary of Site Mitigation Measures2-51
2.12  Crime Prevention Through Environmental  Design (CPTED)2-59
CHAPTER 3  BUILDING DESIGN GUIDANCE3-1
3.1  Architectural3-3
3.1.1  Building Configuration3-3
3.1.2  Space Design3-6
3.1.3  Other Design Considerations3-8
3.2  Building Structural and Nonstructural Systems3-10
3.2.1  Building Design to Achieve a Desired  Protection Level3-10
3.2.2  Progressive Collapse3-10
3.2.3  Loads and Stresses3-13
3.2.4 Good Engineering Practice Guidelines3-14
3.2.5  Building Materials3-16
3.2.6  Methods and References3-16
3.3  Building Envelope3-17
3.3.1  Building Exterior3-17
3.3.2  Exterior Wall Design3-18
3.3.3  Window Design3-20
3.3.4  Doors3-31
3.3.5  Roof System Design3-32
3.4  Mechanical Systems3-33
3.5  Electrical Systems3-44
3.6  Fire Protection Systems3-45
3.7  Communications Systems3-45
3.8  Electronic Security Systems3-46
3.9 Entry-control Stations3-48
3.10 Physical Security Systems3-50
3.11  Summary of Building Envelope Mitigation Measures3-50
CHAPTER 4  EXPLOSIVE BLAST4-1
4.1  Blast Effects4-1
4.1.1  Building Damage4-6
4.1.2  Injuries4-8
4.1.3  Levels of Protection4-8
4.2  Stand-off Distance and the Effects of Blast4-13
4.3  Predicting Blast Effects4-16
4.3.1  Blast Load Predictions4-16
4.3.2  Blast Effects Predictions4-18
CHAPTER 5  CHEMICAL, BIOLOGICAL, AND RADIOLOGICAL MEASURES5-1
5.1  Evacuation5-2
5.2  Sheltering in Place5-2
5.3  Personal Protective Equipment5-5
5.4  Air Filtration and Pressurization5-7
5.4.1  Air Filtration and Cleaning Principles5-8
5.4.2  Applying External Filtration5-20
5.4.3  Applying Internal Filtration  (Recirculation Filter Units)5-24
5.4.4  Radiological Hazards5-25
5.5  Exhausting and Purging5-26
5.6  CBR Detection5-26
5.7  Indications of CBR Contamination5-31
APPENDIX A   Acronyms
APPENDIX B   General Glossary 
APPENDIX C   Chemical, Biological, and Radiological  Terms Glossary 
APPENDIX D   Electronic Security Systems
APPENDIX E   Bibliography
APPENDIX F  Associations and Organization


TABLES
Chapter 1
Table 1-1  Asset Value Scale1-13
Table 1-2  Nominal Building Asset Value Assessment1-14
Table 1-3  Event Profiles for Terrorism and  Technological Hazards1-17
Table 1-4  Homeland Security Threat Conditions1-24
Table 1-5  Site/Building Inherent Vulnerability  Assessment Matrix (Partial Risk 
Assessment)1-25
Table 1-6  Classification Table Extracts1-26
Table 1-7  Selected Extracts -- Recommended  Standards Chart1-27
Table 1-8  Level of Visibility1-29
Table 1-9  Criticality of Target Site1-30
Table 1-10  Target Value to Potential Threat Element1-30
Table 1-11  Aggressor Access to Target1-31
Table 1-12  Target Threat of Hazard (WMD Materials)1-31
Table 1-13  Site Population Capacity1-32
Table 1-14  Potential for Collateral Damage  (Mass Casualties)1-32
Table 1-15  Building Summary Sheet1-33
Table 1-16  Building Ranking1-33
Table 1-17  Simplified Building Ranking Matrix1-34
Table 1-18  Risk Factors Definitions1-38
Table 1-19  Total Risk Color Code1-38
Table 1-20  Site Functional Pre-Assessment  Screening Matrix1-38
Table 1-21  Site Infrastructure Systems  Pre-Assessment Screening Matrix1-39
Table 1-22 Building Vulnerablilty Assessment  Checklist1-46
Chapter 2
Table 2-1 Correlation of Mitigation Measures  to Threats2-54
Chapter 3
Table 3-1 Glazing Protection Levels Based on  Fragment Impact Locations3-21
Table 3-2  Correlation of GSA Glazing Performance  Conditions and DoD Levels of 
Protection  for New Buildings3-22
Chapter 4
Table 4-1 DoD Minimum Antiterrorism (AT)  Standards for New Buildings4-9
Table 4-2  Correlation of DoD Level of Protection  to Incident Pressure4-10
Table 4-3  Damage Approximations4-19
Chapter 5
Table 5-1 Comparison of ASHRAE Standards  52.1 and 52.25-12
Table 5-2  Indicators of a Possible Chemical  Incident5-34
Table 5-3  Indicators of a Possible Biological  Incident5-35
Table 5-4  Indicators of a Possible Radiological  Incident5-36

FIGURES
Chapter 1
Figure 1-1    Recent acts of terrorism1-2
Figure 1-2   Total facilities struck by international  terrorist attacks in 1997-2002 and  
total facilities attacked in 20021-3
Figure 1-3 The assessment process model1-5
Figure 1-4  Satellite imagery/GIS tool1-7
Figure 1-5  Satellite imagery/GIS tool1-8
Figure 1-6 Aggressor weapons1-15
Figure 1-7  Estimated plume from a 1-ton chlorine  spill in Washington, DC1-16
Figure 1-8  Facility system interactions1-23
Figure 1-9  Common system vulnerabilities1-35
Figure 1-10  Non-redundant critical functions  collocated near loading dock1-41
Figure 1-11  Vulnerability examples1-42
Figure 1-12  Typical building design and  construction process1-43
Figure 1-13  Risk management choices1-44
Chapter 2
Figure 2-1 An example of using GIS to identify  adjacent hazards2-5
Figure 2-2 Clustered versus dispersed site layouts2-8
Figure 2-3  Clustering to enhance surveillance opportunities while minimizing views 
into the buildings2-8
Figure 2-4 Streetscape security elements2-17
Figure 2-5 Blocking of sight lines2-20
Figure 2-6 Improper building siting and view  relationships2-21
Figure 2-7 Clear zone with unobstructed views2-21
Figure 2-8 Concept of stand-off distance2-22
Figure 2-9 Stand-off distance and building separation2-23
Figure 2-10 Exclusive and non-exclusive zones2-26
Figure 2-11 Application of perimeter barrier elements2-28
Figure 2-12  Using street closing to create a controlled  access area2-31
Figure 2-13 Sample bollard applications2-33
Figure 2-14 Examples of active and passive vehicle barriers2-35
Figure 2-15 Combined multi-user gate2-37
Figure 2-16 Summary of site mitigation measures2-53
Chapter 3
Figure 3-1 Glazed areas perpendicularly oriented  away from streets3-5
Figure 3-2 Re-entrant corners in a floor plan3-6
Figure 3-3 Offset doors through foyer3-7
Figure 3-4 Side view of a test structure illustrating  performance conditions of Table 3-
23-22
Figure 3-5 An unprotected window subject to a  large explosion3-23
Figure 3-6 Narrow and recessed windows  with sloped sills3-29
Figure 3-7 Sacrificial roof3-33
Figure 3-8 Example of protecting outdoor air intakes3-36
Figure 3-9 Example of elevated air intake3-36
Figure 3-10 Another example of protecting outdoor  air intakes3-37
Figure 3-11 Example of enclosing an existing  vulnerable air intake3-38
Figure 3-12 Physical security devices3-48
Chapter 4
Figure 4-1 Typical pressure-time history4-2
Figure 4-2 Reflected pressure coefficient vs. angle  of incidence4-3
Figure 4-3 Typical impulse waveform4-4
Figure 4-4 Blast pressure effects on a structure4-7
Figure 4-5 Explosives environments - blast range  to effects4-11
Figure 4- 6 Blast analysis of a building for a typical car  bomb detonated in the 
buildings parking lot4-12
Figure 4-7 Blast analysis of a building for a typical  large truck bomb detonated in the  
buildings parking lot4-12
Figure 4-8 Relationship of cost to stand-off distance4-13
Figure 4-9 Stand-off distance and its relationship  to blast impact as modeled on the  
Khobar Towers site4-15
Figure 4-10 Incident overpressure measured in  pounds per square inch, as a function 
of  stand-off distance and net explosive weight  (pounds-TNT)4-17
Chapter 5
Figure 5-1 Universal-fit escape hood5-6
Figure 5-2 Scanning electron microscope image of  a polyester-glass fiber filter5-8
Figure 5-3 Four primary filter collection mechanisms5-9
Figure 5-4 Classic collection efficiency curve5-10
Figure 5-5   A bag filter and HEPA filter5-12
Figure 5-6 Comparison of filter collection efficiency  based on particle size5-13
Figure 5-7 Typical performance of a HEPA 99.97%5-14
Figure 5-8 Scanning electron microscope image of  activated carbon pores5-14
Figure 5-9  Charcoal filter beds5-17
Figure 5-10 UVGI array used for air disinfection with  reflective surfaces5-19
Figure 5-11 A military FFA 580 air filtration system  containing both a HEPA filter and 
an  ASZM-TEDA carbon adsorber as part of  an overpressure system5-21
Figure 5-12 A commercial air filtration unit5-22
Figure 5-13  An IMS chemical detector designed for  installation in HVAC systems  5-
29
Figure 5-14 Placards associated with chemical  incidents5-35
Figure 5-15 Placards associated with biological  incidents5-36
Figure 5-16 Placards associated with radiological  incidents5-36




ASSET VALUE, THREAT/HAZARD, VULNERABILITY, AND RISK   


Mitigating the threat of terrorist attacks against high occupancy buildings is a 
challenging task. It is difficult to predict how, why, and when terrorists may attack. 
Many factors must be considered in creating a safe building environment. This 
chapter presents several methodologies for architects and engineers to quantify risk 
and to identify the most effective mitigation measures to achieve a desired level of 
protection against terrorist attacks at an acceptable cost. The methodologies 
presented herein can be used for new buildings during the design process, as well as 
for existing buildings undergoing renovation. Sections 1.1 to 1.5 will discuss the 
assessment process, asset value assessment, threat/hazard assessment, vulnerability 
assessment, risk assessment, and risk management to help architects and engineers 
identify the best and most cost-effective terrorism mitigation measures for each 
buildings unique security needs. Section 1.6 presents the Building Vulnerability 
Assessment Checklist to support the assessment process.
One of the primary objectives of this manual is to establish a common framework of 
terminology and the transfer of design concepts that have been in use by the United 
States (U.S.) Department of Defense (DoD), military services, the Department of State 
(DOS), and the General Services Administration (GSA) to commercial practice. The 
beginning point is to establish a basis for design by identifying the threat or hazard 
to be designed against. Within the military services, intelligence community, and law 
enforcement, the term "threat" is typically used to describe the design criteria for 
terrorism or manmade disasters. Within the Federal Emergency Management Agency 
(FEMA) and other civil agencies, the term "hazard" is used in several different 
contexts. "Natural hazard" typically refers to a natural event such as a flood, wind, or 
seismic disaster. "Human-caused (or manmade) hazards" are "technological hazards" 
and "terrorism." These are distinct from natural hazards primarily in that they 
originate from human activity. Furthermore, "technological hazards" are generally 
assumed to be accidental and that their consequences are unintended. For the sake 
of simplicity, this manual will use the terms "threat" and "hazard" when referring to 
terrorism and manmade disasters, respectively. 
Terrorism and physical attacks on buildings have continued to increase in the past 
decade. The geographical isolation of the United States is not a sufficient barrier to 
prevent an attack on U.S. cities and citizens. Figures 1-1 and 1-2 demonstrate the far-
reaching incidents and diverse natures and targets of recent terrorist attacks.
Design of buildings to survive natural hazards is a concept that is well understood by 
the design community. Many years of historical and quantitative data, and 
probabilities associated with the cycle, duration, and magnitude of natural hazards 
exist. Conversely, design of buildings that can survive the threat and impact of a 
terrorist attack is based on qualitative factors that evaluate organization 
requirements, recovery efforts and impacts, and loss of personnel and infrastructure, 
but have no predictable period of recurrence or damage probability. Terrorist attacks 
are often categorized as low probability, but potentially high consequence, events. 
Building designs must include physical security measures as an integral part of the 
design process. 
This chapter presents selected methodologies to determine asset value, analyze the 
threat/hazard, and evaluate vulnerabilities to complete the risk assessment. These 
elements of information become the input for determining relative levels of risk. 
Higher risk hazards may require more complex mitigation measures to reduce risk. 
Mitigation measures are conceived by the design professional and are best 
incorporated into the building architecture, building systems, and operational 
parameters, with consideration for life-cycle costs. 
In order to create a safe environment, many factors must be considered. Figure 1-3 
depicts the assessment process presented in this document to help identify the best 
and most cost-effective terrorism mitigation measures for a buildings own unique 
security needs. The first part of the assessment process identifies the value of a 
buildings assets (described in Section 1.1) that need to be protected. The second step 
is to conduct a threat assessment wherein the threat or hazard is identified, defined, 
and quantified (see Section 1.2). For terrorism, the threat is the aggressors (people or 
groups) that are known to exist and that have the capability and a history of using 
hostile actions, or that have expressed intentions for using hostile actions against 
potential targets, as well as on whom there is current credible information on tar-
geting activity (surveillance of potential targets) or indications of preparation for 
terrorist acts. The capabilities and histories of the aggressors include the tactics they 
have used to achieve their ends.
After conducting a threat assessment, the next step is to conduct a vulnerability 
assessment (see Section 1.3). A vulnerability assessment evaluates the potential 
vulnerability of the critical assets against a broad range of identified threats/hazards. 
In and of itself, the vulnerability assessment provides a basis for determining 
mitigation measures for protection of the critical assets. The vulnerability assessment 
is the bridge in the methodology between threat/hazard, asset value, and the 
resultant level of risk.
The next step of the process is the risk assessment (see Section 1.4). The risk 
assessment analyzes the threat, asset value, and vulnerability to ascertain the level of 
risk for each critical asset against each applicable threat. Inherent in this is the 
likelihood or probability of the threat occurring and the consequences of the 
occurrence. Thus, a very high likelihood of occurrence with very small consequences 
may require simple low cost mitigation measures, but a very low likelihood of 
occurrence with very grave consequences may require more costly and complex 
mitigation measures. The risk assessment should provide a relative risk profile. High-
risk combinations of assets against associated threats, with identified vulnerability, 
allow prioritization of resources to implement mitigation measures.
When starting the design process for any new building or the renovation of an 
existing one, various owner, statutory, and building use inputs are required. These 
inputs must be integrated to ensure that mandatory building code requirements are 
met, the building will meet the owners functional needs, and natural and manmade 
hazards are mitigated to an acceptable level. In some cases, mitigation measures to 
enhance security may be in conflict with other design intentions. The assessment 
process helps to ensure an understanding of risk, so that it can be consciously ad-
dressed within the design process with available resources.
For natural hazards (earthquakes, grassland and forest fires, floods, and winds) and 
building fire hazards (technological accidents), information is available in building 
codes, industry standards, and FEMA guidelines. For manmade hazards, the 
suggested course of action is less well defined. The United States has not yet 
developed building standards similar to those of the United Kingdom, which has a 
greater history of contending with repeated terrorism on its home soil. Helpful 
information may be found in a strategic plan or a site master plan, or it may have to 
be developed during initial design through interviews with building owners, staff, 
occupants, utility companies, local law enforcement, and others. 
There are many tools and techniques available to the designer for the development of 
new building designs, the renovation of existing buildings, and mitigation of 
vulnerabilities. Advances in commercial satellite imagery, Geographic Information 
Systems (GIS) (see Figures 1-4 and 1-5), structural hardening, glass fragmentation 
films, physical security systems, and many other building related technologies 
provide the design professional with numerous tools to design buildings to better 
protect occupants from terrorist acts. 
Another challenge for the design team is to present appropriate information to the 
building owner/decision-maker in a manner that allows him or her to make a 
rational, informed decision. Ideally, design basis threats will be identified and agreed 
upon at the earliest stages of design (no later than preliminary design). The reason 
for this is twofold. First, the designer must have a known quantity against which to 
design. Second, by considering all threats/hazards (especially manmade threats) 
early in the design, there are potential synergies among mitigating actions. One miti-
gation strategy can be beneficial against more than one hazard for little difference in 
cost. As an example, designing moment frame connections between floors and 
columns and reinforcing exterior walls can mitigate against winds, explosive blasts, 
and earthquakes. Thus, in order to design mitigation measures for manmade 
hazards, the designer must have some appreciation of the assessment of 
threat/hazard, asset value, vulnerability, and risk to assist the building 
owner/decision-maker. 
Based on the methodologies discussed in this chapter, the assessment process follows 
a logical flow:
_	Asset Value
 Identify criticality of assets 
 Identify number of people in a building
_	Threat/Hazard Assessment
 Identify each threat/hazard
 Define each threat/hazard
 Determine threat level for each threat/hazard
_	Vulnerability Assessment
 Identify site and building systems design issues
 Evaluate design issues against type and level of threat
 Determine level of protection sought for each mitigation measure against each 
threat
_	Risk Assessment
 Likelihood of occurrence
 Impact of occurrence (loss of life, property, and function)
 Determine relative risk for each threat against each asset
 Select mitigation measures that have the greatest benefit/cost for reducing risk
The goal of the assessment process is to achieve the level of protection sought 
through implementation of mitigation measures in the building design. These 
measures may reduce risk by deterring, detecting, denying, or devaluing the potential 
threat element prior to or during execution of an enemy attack. Mitigation measures 
may also reduce risk of damage or injury by providing an acceptable level of pro-
tection if the hazard does occur, which may also serve to further deter an aggressor. 
For example, the Murrah Federal Building in Oklahoma City became the target of an 
aggressor when he was deterred from attacking his primary target, the Federal Bureau 
of Investigation (FBI) building, because it was too difficult to get the attack vehicle 
close to the FBI building. He was able to park immediately adjacent to the Murrah 
Federal Building and successfully target the office of the Bureau of Alcohol, Tobacco, 
and Firearms (ATF), which was located in the Murrah Federal Building.
The remainder of this chapter describes the general concepts of asset value, 
threat/hazard, vulnerability, and risk assessments for manmade disasters and 
presents several methodologies and techniques that can be used by an organization 
in conducting these assessments.
1.1 ASSET VALUE ASSESSMENT
This section will describe how to perform an asset value assessment (the first step of 
the assessment process), to identify people and the asset value. To facilitate 
identifying people and the value of a buildings assets, it is useful to conduct 
interviews of the people who are most familiar with them. Inputs from building 
owners, facility staff, and tenants, as well as any others who can help identify the most 
valuable assets, should be sought. In order to conduct productive interviews, a list of 
areas to be covered should be generated and prioritized prior to the actual interviews. 
Thorough planning and research to generate relevant questions will aid the process 
and yield better results.
An asset is a resource of value requiring protection.1 An asset can be tangible (e.g., 
tenants, buildings, facilities, equipment, activities, operations, and information) or 
intangible (e.g., processes or a companys reputation). In order to achieve the 
greatest risk reduction at the least cost, identifying and prioritizing a buildings 
critical assets is a vital first step in the process to identify the best mitigation 
measures to improve its level of protection prior to a terrorist attack. Recognizing 
that people are a buildings most critical asset, the process described below will help 
identify and prioritize infrastructure where people are most at risk and require 
protection.
Identifying a buildings critical assets is accomplished in a two-step process:
Step 1: Define and understand the buildings core functions and processes
Step 2: Identify building infrastructure
_	Critical components/assets
_	Critical information systems and data
_	Life safety systems and safe haven areas
_	Security systems
1.1.1 Identifying Building Core Functions
The initial step of an asset value assessment is the determination of core functions 
and processes necessary for the building to continue to operate or provide services 
after an attack. The reason for identifying core functions/processes is to focus the 
design team on what a building does, how it does it, and how various threats can 
affect the building. This provides more discussion and results in a better 
understanding of asset value. Factors that should be considered include:
_	What are the buildings primary services or outputs?
_	What critical activities take place at the building?
_	Who are the buildings occupants and visitors?
_	What inputs from external organizations are required for a buildings success?
1.1.2 Identifying Building Infrastructure
After the core functions and processes are identified, an evaluation of building 
infrastructure is the next step. To help identify and value rank infrastructure, the 
following should be considered, keeping in mind that the most vital asset for every 
building is its people:
_	Identify how many people may be injured or killed during a terrorist attack that 
directly affects the infrastructure.
_	Identify what happens to building functions, services, or occupant satisfaction if a 
specific asset is lost or degraded. (Can primary services continue?)
_	Determine the impact on other organizational assets if the component is lost or 
can not function.
_	Determine if critical or sensitive information is stored or handled at the building.
_	Determine if backups exist for the buildings assets.
_	Determine the availability of replacements.
_	Determine the potential for injuries or deaths from any catastrophic event at the 
buildings assets.
_	Identify any critical building personnel whose loss would degrade, or seriously 
complicate the safety of building occupants during an emergency. 
_	Determine if the buildings assets can be replaced and identify replacement costs 
if the building is lost.
_	Identify the locations of key equipment.
_	Determine the locations of personnel work areas and systems.
_	Identify the locations of any personnel operating "outside" a buildings controlled 
areas.
_	Determine, in detail, the physical locations of critical support architectures:
 Communications and information technology (IT - the flow of critical 
information)
 Utilities (e.g., facility power, water, air conditioning, etc.)
 Lines of communication that provide access to external resources and provide 
movement of people (e.g., road, rail, air transportation)
_	Determine the location, availability, and readiness condition of emergency 
response assets, and the state of training of building staff in their use.
1.1.3 Quantifying Asset Value
After a list of a buildings assets or resources of value requiring protection have been 
identified, they should be assigned a value. Asset value is the degree of debilitating 
impact that would be caused by the incapacity or destruction of the buildings assets. 
There are many scales that can be used, each with advantages and disadvantages. 
Because some people are used to working with linguistic scales, although many 
engineers and designers prefer numerical systems, this publication will use a 
combination of a seven-level linguistic scale and a ten-point numerical scale as 
shown in Table 1-1. Obviously, the key asset for every building is its people (e.g., 
employees, visitors, etc.). They will always be assigned the highest asset value as in the 
example below.
Table 1-1: Asset Value Scale

Asset Value
Very High
10
High
8-9
Medium 
High
7
Medium
5-6
Medium Low
4
Low
2-3
Very Low
1

Very High  Loss or damage of the buildings assets would have exceptionally grave 
consequences, such as extensive loss of life, widespread severe injuries, or total loss of 
primary services, core processes, and functions.
High  Loss or damage of the buildings assets would have grave consequences, such 
as loss of life, severe injuries, loss of primary services, or major loss of core processes 
and functions for an extended period of time.
Medium High  Loss or damage of the buildings assets would have serious 
consequences, such as serious injuries or impairment of core processes and functions 
for an extended period of time.
Medium  Loss or damage of the buildings assets would have moderate to serious 
consequences, such as injuries or impairment of core functions and processes.
Medium Low  Loss or damage of the buildings assets would have moderate 
consequences, such as minor injuries or minor impairment of core functions and 
processes.
Low  Loss or damage of the buildings assets would have minor consequences or 
impact, such as a slight impact on core functions and processes for a short period of 
time.
Very Low  Loss or damage of the buildings assets would have negligible 
consequences or impact.
Asset Value Example. A nominal list of assets for a typical building with assigned 
value is presented in Table 1-2. Please note that this is a nominal example; each 
building should tailor its list to its own unique situation.
1.2THREAT/HAZARD ASSESSMENT
1.2.1 Threat/Hazard Identification
With any manmade hazard, it is important to understand who are the people with the 
intent to cause harm. For those people, it is essential to understand their weapons, 
tools, and tactics, realizing that weapons, tools, and tactics can change faster than a 
building can be modified against the threat. The threat/hazard assessment 
information should be sought from local law enforcement, local emergency 
management, the FBI, the Centers for Disease Control and Prevention (CDC), the 
U.S. Department of Homeland Security (DHS), and the Homeland Security Offices 
(HSOs) at the state level. For technological hazards, it is also important to gather 
information from the local fire department and hazardous materials (HazMat) unit, 
Local Emergency Planning Committee (LEPC), and State Emergency Response 
Commission (SERC). LEPC and SERC are local and state organizations established 
under a U.S. Environmental Protection Agency (EPA) program. They identify critical 
facilities in vulnerable zones and generate emergency management plans. 
Additionally, most fire departments understand which industries in the local area 
handle the most combustible materials and the HazMat unit understands who 
handles materials that could have a negative impact upon people and the 
environment. In many jurisdictions, the HazMat unit is part of the fire department.
The aggressors (those people with intent to do harm) seek publicity for their cause, 
monetary gain (in some instances), or political gain through their actions. These 
actions injure or kill people; destroy or damage facilities, property, equipment, or 
resources; or steal equipment, material, or information. Their methods can be forced 
entry tools, vehicles, and surveillance (visual/audio; stand-off or planted). Their 
weapons can include incendiary devices; small arms (rifles and handguns); stand-off 
military-style weapons (rocket propelled grenades or mortars) (see Figure 1-6); 
explosives; and chemical, biological, and radiological agents (CBR, individually or 
combined with explosives to aid in dispersion). 
Explosives include homemade and stolen industrial and military varieties, packaged 
from small to very large (mail bombs to vehicle bombs). Aggressor tactics run the 
gamut: moving vehicle bombs; stationary vehicle bombs; exterior attacks (thrown 
objects like rocks, Molotov cocktails, hand grenades, or hand-placed bombs); stand-
off weapons attacks (military or improvised larger direct and indirect fire weapons); 
ballistic attacks (small arms handled by one individual); covert entries (gaining entry 
by false credentials or circumventing security with or without weapons); mail bombs 
(delivered to individuals); supply bombs (larger bombs processed through shipping 
departments); airborne contamination (CBR agents used to contaminate the air 
supply of a building as notionally (hypothetically) demonstrated in Figure 1-7); and 
waterborne contamination (CBR agents injected into the water supply).
Table 1-3 provides insight into the various manmade hazards to consider and can be 
used as a tool for threat assessments. Note that Table 1-1 combines aspects of tools, 
weapons, explosives, and tactics. Chapters 4 and 5 provide additional information on 
manmade hazards, and Appendix C provides a complete list of CBR agents.
Table 1-3 provides the designer with a general profile of events associated with a 
spectrum of threats/hazards. The next sections will begin the process of quantifying 
a buildings "design basis" by applying a systems engineering evaluation process to 
determine a buildings critical functions, infrastructure, and vulnerabilities using an 
understanding of the aggressors, potential threat elements, a more refined definition 
of the threat/hazard, and methods to evaluate the risk. There are several 
methodologies and assessment techniques that can be used. Historically, the U.S. 
military methodology (with a focus on explosive effects, CBR, and personnel 
protection) has been used extensively for military installations and other national 
infrastructure assets. The DOS adopted many of the same blast and CBR design 
criteria, and the GSA further developed criteria for federal buildings as a result of the 
attack on the Murrah Federal Building. The Department of Commerce (DOC) 
Critical Infrastructure Assurance Office (CIAO) established an assessment framework, 
which focused on information technology infrastructure. 

1.2.2 Threat Definition of Physical Attack on a Building
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 and 
the better the building is designed to withstand an attack, the better the odds the 
building will not be attacked or, if attacked, will suffer less damage. Terrorists 
generally select targets that have some value as a target, such as an iconic commercial 
property, symbolic government building, or structure likely to inflict significant 
emotional or economic damage such as a shopping mall or major seaport. A 
manmade threat/hazard analysis requires interface with security and intelligence 
organizations that understand the locality, the region, and the nation. These 
organizations include the police department (whose jurisdiction includes the 
building or site), the local state police office, and the local office of the FBI. In many 
areas of the country, there are threat coordinating committees, including FBI Joint 
Terrorism Task Forces, that facilitate the sharing of information. A common method 
to evaluate terrorist threats is to analyze five factors: existence, capability, history, 
intention, and targeting.
Existence addresses the questions: Who is hostile to the assets, organization, or 
community of concern? Are they present or thought to be present? Are they able to 
enter the country or are they readily identifiable in a local community upon arrival?
Capability addresses the questions: What weapons have been used in carrying out past 
attacks? Do the aggressors need to bring them into the area or are they available 
locally?
History addresses the questions: What has the potential threat element done in the 
past and how many times? When was the most recent incident and where, and against 
what target? What tactics did they use? Are they supported by another group or 
individuals? How did they acquire their demonstrated capability?
Intention addresses the questions: What does the potential threat element or 
aggressor hope to achieve? How do we know this (e.g., published in books or news 
accounts, speeches, letters to the editor, informant)?
Targeting addresses the questions: Do we know if an aggressor (we may not know 
which specific one) is performing surveillance on our building, nearby buildings, or 
buildings that have much in common with our organization? Is this information 
current and credible, and indicative of preparations for terrorist operations 
(manmade hazards)?
The threat/hazard analysis for any building can range from a general threat/hazard 
scenario to a very detailed examination of specific groups, individuals, and tactics 
that the building may need to be designed to repel or defend against.
A terrorist or aggressor will analyze the building or target as shown in Figure 1-8 to 
determine the type of attack, type of weapon, and tactics to employ to defeat the 
building or critical mission/business function. 
The Homeland Security Advisory System has five threat levels that provide a general 
indication of risk of terrorist attack. In Table 1-4, the five factors commonly used to 
evaluate terrorist threats have been layered onto the Homeland Security Advisory 
levels. If the anticipated threat or projected use of the building warrants it, a detailed 
threat analysis should be developed in coordination with local law enforcement, 
intelligence, and civil authorities in order to more quantitatively determine the 
vulnerability or risk. Having conducted a threat analysis and having a good con-
ceptual idea of the preliminary building design and site layout, the next step is to 
conduct a vulnerability assessment to identify weaknesses that can be exploited by an 
aggressor and to help identify specific design features and establish operational 
parameters to mitigate them.

1.3VULNERABILITY ASSESSMENT
Knowing the expected threat/hazard capability allows the designer to integrate the 
threat knowledge with specific building and site information by conducting a 
vulnerability assessment. A vulnerability assessment is an in-depth analysis of the 
building functions, systems, and site characteristics to identify building weaknesses 
and lack of redundancy, and determine mitigations or corrective actions that can be 
designed or implemented to reduce the vulnerabilities. A vulnerability assessment 
should be performed for existing buildings and the process incorporated into the 
design for new construction and renovation.
Table 1-5 contains vulnerability and consequence aspects and provides an objective 
approach to determine a relative value of vulnerability for the building or site. An 
alternate method for determining a relative value is presented in Table 1-6, from the 
U.S. Department of Justice (DOJ), as applicable to GSA buildings. This method 
provides a suggestion of "security measures" for typical sizes and types of sites, in 
addition to a transferable example of appropriate security measures for typical loca-
tions and occupancies. Tables 1-5 and 1-6 address operational, consequential, and 
inherent characteristics that contribute to vulnerability. They are a first step and 
should be used in conjunction with a more detailed vulnerability assessment such as 
the Building Vulnerability Assessment Checklist (see Table 1-22).
Table 1-7 is an example of one approach to implement minimum building design 
standards to mitigate terrorist events following the methodology of Table 1-6. Note 
that an evaluation or vulnerability assessment still needs to be done before 
incorporating any mitigation measures. 

Level**
Typical Location
Examples of Tenant 
Agencies***
Security Measures (based 
on evaluation) 
 I
10 Employees (Federal)
2,500 Square Feet
Low Volume Public Contact
Small "Store Front" Type Operation 
Local Office
District Office
Visitor Center
USDA Office
Ranger Station
Commercial Facilities
Industrial/Manufacturing 
Health Care
High Security Locks
Intercom
Peep Hole (Wide View)
Lighting w/Emergency 
Backup Power
Controlled Utility Access 
Annual Employee Security 
Training
  II
11 - 150 Employees (Federal) 
2,500 - 80,000 Square Feet
Moderate Volume Public Contact
Routine Operations Similar to 
Private Sector and/or Facility Shared 
with Private Sector
Public Officials
Park Headquarters
Regional/State Offices
Commercial Facilities
Industrial
Manufacturing
Health Care
Entry Control Package 
w/Closed Circuit 
Television (CCTV)
Visitor Control/Screening
Shipping/Receiving 
Procedures
Guard/Patrol Assessment
Intrusion Detection 
w/Central Monitoring
CCTV Surveillance (Pan-
Tilt, Zoom System)
Duress Alarm w/Central 
Monitoring
 III
151 - 450 Employees (Federal) 
Multi-Story Facility
80,000 - 150,000 Square Feet
Moderate/High Volume Public 
Contact
Agency Mix:
 Law Enforcement Operations
 Court Functions
 Government Records
Inspectors General
Criminal Investigations
Regional/State Offices
GSA Field Office
Local Schools 
Commercial Facilities
Industrial
Manufacturing
Health Care
Guard Patrol on Site
Visitor Control/Screening
Shipping/Receiving 
Procedures
Intrusion Detection 
w/Central Monitoring
CCTV Surveillance (Pan-
Tilt/Zoom System)
Duress Alarm w/Central 
Monitoring
 IV 
>450 Employees (Federal)
Multi-Story Facility
>150,000 Square Feet
High Volume Public Contact
High-Risk Law 
Enforcement/Intelligence Agencies
District Court
Significant Buildings and 
Some Headquarters
Federal Law Enforcement 
Agencies
Local Schools, Universities
Commercial Facilities
Health Care
Extend Perimeter 
(Concrete/Steel Barriers)
24-Hour Guard Patrol
Adjacent Parking Control
Backup Power System
Hardened Parking Barriers
  V
Level IV Profile and Agency/Mission 
Critical to National Security
Principal Department 
Headquarters
Agency-Specific

* SOURCE:  U.S. DEPARTMENT OF JUSTICE, VULNERABILITY ASSESSMENT OF FEDERAL FACILITIES, JUNE 28, 1995
  NOTES: ** ASSIGNMENT OF LEVELS TO BE BASED ON AN "ON-SITE" RISK ASSESSMENT/EVALUATION***EXAMPLES OF TYPICAL (BUT NOT LIMITED 
TO) TENANT AGENCIES FOR THIS LEVEL FACILITY
Table 1-5: Selected Extracts -- Recommended Standards Chart*



LEVEL

I
II
III
IV
V
PERIMETER SECURITY
Parking
Control of Facility Parking
D
D
M
M
M
Control of Adjacent Parking
D
D
D
S
S
Avoid Leases Where Parking Cannot be Controlled
D
D
D
D
D
Leases Should Provide Security Control for Adjacent Parking
D
D
D
D
D
Post Signs and Arrange for Towing Unauthorized Vehicles
S
S
M
M
M
ID System and Procedures for Authorized Parking (Placard, Decal, Card 
Key, etc.)
D
D
M
M
M
Adequate Lighting for Parking Areas
D
D
M
M
M
Closed Circuit Television (CCTV) Monitoring
CCTV Surveillance Cameras with Time Lapse Video Recording
D
S
S
M
M
Post Signs Advising of 24-Hour Video Surveillance
D
S
S
M
M
Lighting
Lighting with Emergency Power Backup
M
M
M
M
M
Physical Barriers
Extend Physical Perimeter with Barriers (Concrete and/or Steel 
Composition)
N/
A
N/
A
D
S
S
Parking Barriers
N/
A
N/
A
D
S
S
ENTRY SECURITY
Receiving/Shipping
Review Receiving/Shipping Procedures (Current)
M
M
M
M
M
Implement Receiving/Shipping Procedures (Modified)
D
S
M
M
M
Access Control
Evaluate Facility for Security Guard Requirements
D
S
M
M
M
Security Guard Patrol
D
D
S
S
S
Intrusion Detection System with Central Monitoring Capability
D
S
M
M
M
Upgrade to Current Life Safety Standards (Fire Detection, Fire 
Suppression Systems, etc.)
M
M
M
M
M
Entrances/Exits
X-Ray and Magnetometer at Public Entrances
N/
A
D
S
S
M
Require X-Ray Screening of All Mail/Packages
N/
A
D
S
M
M
Peep Holes
S
S
N/
A
N/
A
N/
A
Intercom
S
S
N/
A
N/
A
N/
A
Entry Control w/CCTV and Door Strikes
D
S
N/
A
N/
A
N/
A
High Security Locks
M
M
M
M
M
INTERIOR SECURITY
Employee/Visitor Identification
Agency Photo ID for all Personnel Displayed at all Times
N/
A
D
S
M
M
Visitor Control/Screening System
D
M
M
M
M
Visitor Identification Accountability System
N/
A
D
S
M
M
Establish ID Issuing Authority
S
S
S
M
M
Utilities
Prevent Unauthorized Access to Utility Areas
S
S
M
M
M
Provide Emergency Power to Critical Systems (Alarm Systems, Radio 
Communications, Computer Facilities, etc.)
M
M
M
M
M
Daycare Centers
Evaluate Whether to Locate Daycare Facilities in Buildings with High-
Threat Activities
N/
A
M
M
M
M
Compare Feasibility of Locating Daycare in Facilities Outside 
Locations
N/
A
M
M
M
M
SECURITY PLANNING
Tenant Assignment
Collocate Agencies with Similar Security Needs
D
D
D
D
D
Do Not Collocate High-/Low-Risk Agencies
D
D
D
D
D
Administrative Procedures
Arrange for Employee Parking In/Near Building After Normal Work 
Hours
S
S
S
S
S
Conduct Background Security Checks and/or Establish Security 
Control Procedures for Service Contract Personnel
M
M
M
M
M
Construction/Renovation
Install Mylar Film on all Exterior Windows (Shatter Protection)
D
D
S
M
M
Review Current Projects for Blast Standards
M
M
M
M
M
Review/Establish Uniform Standards for Construction
M
M
M
M
M
Review/Establish New Design Standard for Blast Resistance
S
S
M
M
M
Establish Street Setback for New Construction
D
D
S
M
M

* SOURCE: EXTRACTS FROM U.S. DEPARTMENT OF JUSTICE STUDY "VULNERABILITY ASSESSMENT OF FEDERAL FACILITIES," JUNE 28, 1995
In the preceding tables, determining which "level" most nearly reflects the site and 
building under design or renovation may help to identify which security standards 
would be most appropriate to apply. The GSA method provides a more detailed 
analysis of a building vulnerability and good suggestions for security measures that 
may be appropriate to design into a building for certain occupancies and sizes of 
facilities. A more quantitative evaluation or ranking of one building compared to 
another may be required in some instances (e.g., where a building owner and 
designer may need to know the relative risk of one building compared to an 
equivalent building on another site or on the same campus). 
The DOJ, Office of Justice Programs (OJP) provides an objective approach to 
determining vulnerability (see U.S. Department of Justice, Fiscal Year 1999 State 
Domestic Preparedness Equipment Program, Assessment and Strategy Development 
Tool Kit, May 15, 1999). DOJs Threat/Hazard Assessment uses seven factors that are 
Threat Assessment and Consequence Management oriented, and provides a 
quantitative means to rank buildings. It requires rating each of the seven areas and 
summing the ratings to determine the overall ranking for the building or site. This 
approach is as follows:
1. Level of Visibility (Table 1-8)
What is the perceived awareness of the targets existence and the visibility of the 
target to the general populace, or to the terrorist in particular?
2. Asset Value of Target Site (Individual Asset or Assets Accumulated within Building  
Table 1-9)
What is the usefulness of the asset(s) to the population, economy, government, 
company, or organization? Also consider the impact on continuity of operations, 
hampering of emergency response, and general potential consequences. Table 1-9 
could be used more than once if the value of the asset(s) impacts more than one 
critical area.
3. Target Value to Potential Threat Element/Aggressor (Table 1-10)
Does the target serve the ends of the aggressors identified in the Threat Assessment 
based on motivations (political, religious, racial, environmental, and special 
interests)? Table 1-10 should help to capture these motivations. 
4. Aggressor Access to Target (Table 1-11)
Does the target have available ingress and egress for a potential aggressor?

5. Target Threat of Hazard (Table 1-12)
Are CBR materials present in quantities that could become hazardous if released? 
These quantities could be on site or in relatively close proximity so that a theft or an 
accident could render them a hazard to the building or site. Take into consideration 
distance from building (a 1-mile radius is suggested around the building), the 
prevailing wind direction, the slope of the terrain, and the quantity of materials 
present. 
6. Site Population Capacity (Table 1-13)
What is the maximum number of individuals at the building or site at a given time? 
This could be standard worst case occupancy during an average day or peak 
occupancy at a designated time (e.g., a movie theater). 
Table 1-13: Site Population Capacity


Rating Value
0
0
1 to 250
1
251 to 500
2
501 to 1,000
3
1,001 to 5,000
4
> 5,000
5

7. Potential for Collateral Damage (Mass Casualties - Table 1-14) Address potential 
collateral mass casualties within a 1-mile radius of the target site. Number ranges 
indicate inhabitants within a 1-mile radius of the site. 
Table 1-14: Potential for Collateral Damage (Mass Casualties)


Rating Value
 0-100
0
101 to 500
1
501 to 1,000
2
1,001 to 2,000
3
2,001 to 5,000
4
> 5,000
5

Each building is assessed and scored (see Table 1-15). Tables 1-15 and 1-16 contain a 
nominal example.

Table 1-15: Building Summary Sheet

Building/Target Name
Score
Visibility
4
Criticality
3
Value
4
Access
2
Threat of Hazard
0
Site Population
3
Collateral Mass 
Casualties
3
Total Score
19

The total building score can be used to rank multiple buildings (see Table 1-16) and 
quantitatively provides an analysis of building vulnerability from a site perspective. 
Table 1-16: Building Ranking

Rankin
g
Building/Target Name
Total Score
1
ABC Building
23
2
DEF Building
19
3
GHI Building
14

This evaluation methodology can be applied to all building types (see Foreword). The 
result is independent of facility/occupancy type, except for the type of influence on 
population and siting.
An alternate approach is shown in Table 1-17, which uses a simplified matrix to rank 
the order of buildings using a numerical score of 1 (low) to 5 (high). The evaluation 
factors can be developed for each building use or owner-specific criteria. For Table 1-
17, the factors shown illustrate a health care provider scenario:
_		Criticality of Function: How critical is the building and function to the 
organization?
_		Location: Is the building near federal buildings, major transportation, or 
iconic properties?
_		Occupancy of Building: Are occupants mobile or non-ambulatory?
_		Involvement in Community: Does the building or staff provide unique 
capabilities? 
_		Critical External Commitments: Does the building support other 
organizations or missions?
The objective of Tables 1-1 through 1-17 or similar assessment methodologies is to 
provide an analysis of a building, facility, or site and to identify the buildings that are 
most vulnerable from a given threat/hazard matched against specific building type or 
function. Having the ranked list of buildings, the next step is to conduct an in-depth 
vulnerability assessment of the building. The building assessment is to evaluate 
specific design and architectural features and identify all vulnerabilities of the 
building functions and building systems. Frequently, single-point-vulnerabilities 
exist, which are critical functions or systems that lack redundancy and, if damaged by 
an attack, would result in immediate organization disruption or loss of capability. 
These are generally the highest risk vulnerabilities. Figure 1-9 illustrates the common 
system vulnerabilities.
1.4 RISK ASSESSMENT
Risk is the potential for a loss of or damage to an asset. It is measured based upon the 
value of the asset in relation to the threats and vulnerabilities associated with it. Risk 
is based on the likelihood or probability of the hazard occurring and the conse-
quences of the occurrence. A risk assessment analyzes the threat (probability of 
occurrence), and asset value and vulnerabilities (consequences of the occurrence) to 
ascertain the level of risk for each asset against each applicable threat/hazard. The 
risk assessment provides engineers and architects with a relative risk profile that 
defines which assets are at the greatest risk against specific threats. Chapters 2 and 3 
explore mitigation measures to reduce the vulnerability and risk for valuable assets 
with a high risk.
There are numerous methodologies and technologies for conducting a risk 
assessment. One approach is to assemble the results of the asset value assessment, 
threat assessment, and vulnerability assessment, and determine a numeric value of 
risk for each asset and threat/hazard pair in accordance with the following formula:
Risk = Asset Value x Threat Rating x Vulnerability Rating
This methodology can be used for new buildings during the design process, as well as 
for existing structures. The first task is to identify the value of assets and people that 
need to be protected. Next, a threat assessment is performed to identify and define 
the threats and hazards that could cause harm to a building and its inhabitants. After 
threats and assets are identified, a vulnerability assessment is performed to identify 
weaknesses that might be exploited by a terrorist or aggressor. Using the results of 
the asset value, threat, and vulnerability assessments, risk can be computed.
After the architect and building engineer know how people and assets are at greatest 
risk against specific threats, they can then identify mitigation measures to reduce 
risk. Because it is not possible to completely eliminate risk, and every project has 
resource limitations, architects and engineers must analyze how mitigation measures 
would affect risk and decide on the best and most cost-effective measures to 
implement to achieve the desired level of protection (risk management). 
There are numerous checklists and techniques to use for conducting an individual 
building risk assessment. A simplified approach is presented in Tables 1-18 through 
1-21. The tables are used as a pre-assessment screening tool by the assessor who con-
ducts an interview with several key staff members (e.g., building owner, security, site 
management, key function representatives, etc.). The interview provides a consensus 
judgment of the relative risk or vulnerability of functions or systems and should also 
identify system interdependencies. Table 1-19 provides both a quantitative score and 
color code to objectively and visually determine the functions and systems that have 
been determined to be at risk. Engineers, architects, or experienced assessors could 
perform a short walk-through and conduct the pre-assessment interview of an 
existing building in less than a day. For a new building, the pre-screening results can 
be used by the designer to focus the design team on incorporating features and 
redundancies to reduce vulnerabilities and risk.
In the risk assessment approach presented in Tables 1-18 through 1-21, three factors 
or elements of risk are considered for each function or system against each threat 
previously identified. The first factor is the value of the asset or degree of debilitating 
impact that would be caused by the incapacity or destruction of the asset. A value on a 
scale of 1 to 10 is assigned (as shown in Table 1-18), 1 being a very low impact or 
consequence and 10 being very high or an exceptionally grave consequence. The next 
factor is the threat rating or subjective judgment of a terrorist threat based on 
existence, capability, history, intentions, and targeting. Again, on a scale of 1 to 10, 1 
is a very low probability and 10 is a very high probability of a terrorist attack. The third 
factor of risk is vulnerability, or any weaknesses that can be exploited by an aggressor. 
A value of 1 to 10 is assigned, 1 being very low or no weaknesses exist, and 10 being 
very high vulnerability, meaning one or more major weaknesses make an asset 
extremely susceptible to an aggressor. Multiplying the values assigned to each of the 
three factors provides quantification of total risk. The total risk for each function or 
system against each threat is assigned a color code in accordance with Table 1-19. 
The results of the risk assessment should be used to help prioritize which mitigation 
measures should be adopted, given limited resources, in order to achieve a desired 
level of protection. 

Table 1-18: Risk Factors Definitions

Very High
10
High
8-9
Medium High
7
Medium
5-6
Medium Low
4
Low
2-3
Very Low
1

Table 1-19: Total Risk Color Code


Low Risk
Medium Risk
High Risk
Risk Factors 
Total
1-60
61-175
 176

Table 1-21: Site Infrastructure Systems Pre-Assessment Screening Matrix*

Function
Cyber 
Attack
Armed Attack (single 
gunman)
Vehicle 
Bomb
CBR 
Attack
Site
48
80
108
72
Asset Value
4
4
4
4
Threat Rating
4
4
3
2
Vulnerability Rating
3
5
9
9
Architectural
40
40
135
20
Asset Value
5
5
5
5
Threat Rating
8
4
3
2
Vulnerability Rating
1
2
9
2
Structural Systems
24
32
240
16
Asset Value
8
8
8
8
Threat Rating
3
4
3
2
Vulnerability Rating
1
1
10
1
Envelope Systems
84
112
189
112
Asset Value
7
7
7
7
Threat Rating
6
4
3
2
Vulnerability Rating
2
4
9
8
Utility Systems
112
56
168
42
Asset Value
7
7
7
7
Threat Rating
8
4
3
2
Vulnerability Rating
2
2
8
3
Mechanical Systems
42
56
105
126
Asset Value
7
7
7
7
Threat Rating
6
4
3
2
Vulnerability Rating
1
2
5
9
Plumbing and Gas Systems
40
40
120
70
Asset Value
5
5
5
5
Threat Rating
8
4
3
2
Vulnerability Rating
1
2
8
7
Electrical Systems
42
84
189
28
Asset Value
7
7
7
7
Threat Rating
8
4
3
2
Vulnerability Rating
1
3
9
2
Fire Alarm Systems
162
108
216
36
Asset Value
9
9
9
9
Threat Rating
6
4
3
2
Vulnerability Rating
3
3
8
2
IT/Communications 
Systems
512

192
32
Asset Value
8
8
8
8
Threat Rating
8
4
3
2
Vulnerability Rating
8
2
8
2

     * NOTIONAL DATA INSERTED FOR DEMONSTRATION PURPOSES.
The functions and infrastructure analysis will identify the geographic distribution 
within the building and interdependencies between critical assets. Ideally, the 
functions should have geographic dispersion as well as a pre-determined recovery site 
or alternate work location. Similarly, critical infrastructure should have geographic 
dispersion and backup. Figure 1-10 shows an example of a building that has 
numerous critical functions and infrastructure collocated, which creates a single-
point vulnerability as illustrated below. A bomb or CBR attack entering through the 
loading dock could impact the telecommunications, data, uninterrupted power 
supply (UPS), generator, and other key infrastructure systems.
As a minimum, those critical assets assessed to be at highest risk should receive an 
on-site vulnerability assessment using the Building Vulnerability Assessment 
Checklist in Table 1-22. The vulnerability assessment may change the risk rating of 
assets due to the identification of accessible critical nodes, the ease of attack using a 
common tactic, or some other factor that makes the building more attractive as a 
target or more susceptible to damage that could result in casualties or irrecoverable 
system damage. The photographs in Figure 1-11 illustrate some examples of single-
point vulnerabilities of systems and infrastructure. 
1.5 RISK MANAGEMENT
Traditionally, the building regulatory system has addressed natural disaster 
mitigation (hurricane, tornado, flood, earthquake, windstorm, and snow storm) 
through prescriptive building codes supported by well-established and accepted 
reference standards, regulations, inspection, and assessment techniques. Some man-
made risks (e.g., HazMat storage) and specific societal goals (energy conservation 
and life safety) have also been similarly addressed. However, the building regulation 
system has not yet fully addressed most manmade hazards or terrorist threats.
Soon after September 11, 2001, the New York City Building Department initiated an 
effort to analyze the building code with regard to terrorist threats. The task force 
issued a report recommending code changes based on the attack on the World Trade 
Center. The National Fire Protection Association (NFPA) has a committee on 
premises security and security system installation standards. These advances may 
some day result in the building regulatory system developing more prescriptive 
building codes to mitigate security threats.
In the absence of such regulations, the designer needs to understand on what threat 
the design is based. Just like seismic design requires an understanding of geology, 
soil structure, and the maximum credible earthquake accelerations possible at a 
given location, the site designer needs to comprehend the bomb size, vehicle size, 
and gun or other weapon size to provide an appropriate level of protection. The size 
of threat and desired level of protection are equally important to the design. For most 
cases across the United States, the threats and risks for a specific building will be low. 
For buildings at a higher threat and risk, higher standards and performance may be 
required. The Department of Defense (DoD), GSA, and DOS all have established 
processes to identify design basis threats for their facilities.
The typical building design and construction process is sequential, progressing from 
identifying building use and design goals through actual construction. This process 
is illustrated in Figure 1-12.
In every design and renovation project, the owner ultimately has three choices when 
addressing the risk posed by terrorism. He or she can:
1. Do nothing and accept the risk
2. Perform a risk assessment and manage the risk by installing reasonable mitigation 
measures
3. Harden the building against all threats to achieve the least amount of risk
Figure 1-13 is a graphical representation of the three choices. Since September 11, 
2001, terrorism has become a dominant concern. Life, safety, and security issues 
should be a design goal from the beginning. 
Table 1-22 contains key questions that designers may use to determine vulnerabilities 
of an existing building or a new construction in order to focus resources and 
minimize the impacts of potential terrorist attacks or technological accidents.
1.6 BUILDING VULNERABILTY ASSESSMENT CHECKLIST 
The Building Vulnerability Assessment Checklist (Table 1-22) is based on the 
checklist developed by the Department of Veterans Affairs (VA) and compiles many 
best practices based on technologies and scientific research to consider during the 
design of a new building or renovation of an existing building. It allows a consistent 
security evaluation of designs at various levels. The checklist can be used as a 
screening tool for preliminary design vulnerability assessment. In addition to 
examining design issues that affect vulnerability, the checklist includes questions 
that determine if critical systems continue to function in order to enhance 
deterrence, detection, denial, and damage limitation, and to ensure that emergency 
systems function during a threat or hazard situation.
The checklist is organized into the 13 sections listed below. To conduct a 
vulnerability assessment of a building or preliminary design, each section of the 
checklist should be assigned to an engineer, architect, or subject matter expert who is 
knowledgeable and qualified to perform an assessment of the assigned area. Each 
assessor should consider the questions and guidance provided to help identify 
vulnerabilities and document results in the observations column. If assessing an 
existing building, vulnerabilities can also be documented with photographs, if pos-
sible. The results of the 13 assessments should be integrated into a master 
vulnerability assessment and provide a basis for determining vulnerability ratings 
during the assessment process. 

1. Site
2. Architectural
3. Structural Systems
4. Building Envelope
5. Utility Systems
6. Mechanical Systems (heating, ventilation, and air conditioning (HVAC) and CBR)
7. Plumbing and Gas Systems
8. Electrical Systems
9. Fire Alarm Systems
10.  Communications and Information Technology (IT) Systems
11.  Equipment Operations and Maintenance
12.  Security Systems
13.  Security Master Pla


FEDERAL EMERGENCY MANAGEMENT AGENC


FEDERAL EMERGENCY MANAGEMENT AGENC


U.S. AIR FORC


Figure 1-1   Recent acts of terrorism (clockwise left to right, U.S. Pentagon, Arlington, VA; World Trade 
Center, New York, NY; Murrah Federal Building, Oklahoma City, OK


SOURCE: DEPARTMENT OF STATE PATTERNS OF GLOBAL TERRORISM 200


Figure 1-2 Total facilities struck by international terrorist attacks in 1997-2002 and total facilities attacked 
in 2002


Figure 1-3The assessment process mode


Figure 1-4 Satellite imagery/GIS too


Figure 1-5 Satellite imagery/GIS too


Deter: The process of making the target inaccessible or difficult to defeat with the weapon or tactic selected. 
It is usually accomplished at the site perimeter using highly visible electronic security systems, fencing, 
barriers, lighting and security personnel; and in the building by securing access with locks and electronic 
monitoring devices.
Detect: The process of using intelligence sharing and security services response to monitor and identify the 
threat before it penetrates the site perimeter or building access points.
Deny: The process of minimizing or delaying the degree of site or building infrastructure damage or loss of 
life or protecting assets by designing or using infrastructure and equipment designed to withstand blast and 
chemical, biological, or radiological effects.
Devalue:  The process of making the site or building of little to no value or consequence, from the terrorists 
perspective, such that an attack on the facility would not yield their desired result


1 Appendix B is a glossary of assessment and security terminology. Appendix C contains chemical, biological, and radiological terms


Table 1-2: Nominal Building Asset Value Assessment

Asset
Value
Numeric Value
Site
Medium Low
4
Architectural
Medium
5
Structural Systems
High
8
Envelope Systems
Medium 
High
7
Utility Systems
Medium 
High
7
Mechanical Systems
Medium 
High
7
Plumbing and Gas Systems
Medium
5
Electrical Systems
Medium 
High
7
Fire Alarm Systems
High
9
IT/Communications Systems
High
8


Figure 1-6 Aggressor weapon


Figure 1-7 Estimated plume from a 1-ton chlorine spill in Washington, D


Table 1-3: Event Profiles for Terrorism and Technological Hazards



Threat/Hazard
Application 
ode
Duratio
n
Extent of 
Effects;Static/Dynamic
Mitigating and 
Exacerbating Conditions


Improvised Explosive 
Device (Bomb)
- Stationary Vehicle
- Moving Vehicle
- Mail
- Supply
- Thrown
- Placed
- Personnel
Detonation of 
explosive device on 
or near target; via 
person, vehicle, or 
projectile. 
Instantaneous; 
additional 
secondary 
devices may 
be used, 
lengthening 
the duration 
of the 
threat/hazard 
until the 
attack site is 
determined to 
be clear. 
Extent of 
damage is 
determined by 
type and 
quantity of 
explosive. 
Effects 
generally static 
other than 
cascading 
consequences, 
incremental 
structural 
failure, etc. 
Blast energy at a 
given stand-off is 
inversely proportional 
to the cube of the 
distance from the 
device; thus, each 
additional increment 
of stand-off provides 
progressively more 
protection. 
Exacerbating 
conditions include 
ease of access to 
target; lack of 
barriers/shielding; 
poor construction; 
and ease of 
concealment of 
device.
Chemical Agent
- Blister
- Blood
- 
Choking/Lung/Pulm
onary
- Incapacitating
- Nerve
- Riot Control/Tear 
Gas
- Vomiting

Liquid/aerosol 
contaminants can 
be dispersed using 
sprayers or other 
aerosol generators; 
liquids vaporizing 
from 
puddles/containers; 
or munitions.
Chemical 
agents may 
pose viable 
threats for 
hours to 
weeks, 
depending on 
the agent and 
the conditions 
in which it 
exists.
Contamination 
can be carried 
out of the 
initial target 
area by 
persons, 
vehicles, 
water, and 
wind. 
Chemicals 
may be 
corrosive or 
otherwise 
damaging over 
time if not 
remediated. 
Air temperature can 
affect evaporation of 
aerosols. Ground 
temperature affects 
evaporation of 
liquids. Humidity 
can enlarge aerosol 
particles, reducing 
the inhalation hazard. 
Precipitation can 
dilute and disperse 
agents, but can spread 
contamination. Wind 
can disperse vapors, 
but also cause target 
area to be dynamic. 
The micro-
meteorological effects 
of buildings and 
terrain can alter travel 
and duration of 
agents. Shielding in 
the form of sheltering 
in place may protect 
people and property 
from harmful effects. 


Table 1-3: Event Profiles for Terrorism and Technological Hazards* (continued



Threat/Hazard
Application 
Mode
Duratio
n
Extent of 
Effects;Static/Dynamic
Mitigating and 
Exacerbating Conditions

Arson/Incendiary 
Attack
Initiation of fire or 
explosion on or 
near target via 
direct contact or 
remotely via 
projectile. 
Generally 
minutes to 
hours. 
Extent of damage 
is determined by 
type and quantity 
of device 
/accelerant and 
materials present 
at or near target. 
Effects generally 
static other than 
cascading 
consequences, 
incremental 
structural failure, 
etc. 
Mitigation factors include 
built-in fire detection and 
protection systems and fire-
resistive construction 
techniques. Inadequate 
security can allow easy 
access to target, easy 
concealment of an 
incendiary device, and 
undetected initiation of a 
fire. Non-compliance with 
fire and building codes as 
well as failure to maintain 
existing fire protection 
systems can substantially 
increase the effectiveness of 
a fire weapon.
Armed Attack
- Ballistics 
(small arms)
- Stand-off 
Weapons 
(rocket 
propelled 
grenades, 
mortars) 
Tactical assault or 
sniper attacks from 
a remote location.
Generally 
minutes to 
days.
Varies, based 
upon the 
perpetrators 
intent and 
capabilities.
Inadequate security can 
allow easy access to target, 
easy concealment of 
weapons, and undetected 
initiation of an attack.
Biological Agent
- Anthrax
- Botulism
- Brucellosis
- Plague
- Smallpox
- Tularemia
- Viral 
Hemorrhagic 
Fevers
- Toxins 
(Botulinum, 
Ricin, 
Staphylococ-
cal Enterotoxin 
B, T-2 
Mycotoxins)
Liquid or solid 
contaminants can 
be dispersed using 
sprayers/aerosol 
generators or by 
point or line 
sources such as 
munitions, covert 
deposits, and 
moving sprayers. 
May be directed at 
food or water 
supplies.
Biological 
agents may 
pose viable 
threats for 
hours to 
years, 
depending 
on the agent 
and the 
conditions 
in which it 
exists.
Depending on the 
agent used and 
the effectiveness 
with which it is 
deployed, 
contamination 
can be spread via 
wind and water. 
Infection can be 
spread via human 
or animal vectors. 
Altitude of release above 
ground can affect 
dispersion; sunlight is 
destructive to many bacteria 
and viruses; light to 
moderate winds will 
disperse agents, but higher 
winds can break up aerosol 
clouds; the micro-
meteorological effects of 
buildings and terrain can 
influence aerosolization and 
travel of agents. 


Table 1-3: Event Profiles for Terrorism and Technological Hazards* (continued



Threat/Hazard
Application 
Mode
Duratio
n
Extent of 
Effects;Static/Dynamic
Mitigating and 
Exacerbating Conditions

Cyberterrorism
Electronic attack 
using one computer 
system against 
another.
Minutes to days.
Generally no direct 
effects on built 
environment. 
Inadequate security 
can facilitate access to 
critical computer 
systems, allowing 
them to be used to 
conduct attacks.
Agriterrorism
Direct, generally 
covert 
contamination of 
food supplies or 
introduction of 
pests and/or disease 
agents to crops and 
livestock.
Days to months.
Varies by type of 
incident. Food 
contamination 
events may be 
limited to discrete 
distribution sites, 
whereas pests and 
diseases may spread 
widely. Generally 
no effects on built 
environment. 
Inadequate security 
can facilitate 
adulteration of food 
and introduction of 
pests and disease 
agents to crops and 
livestock.
Radiological 
Agent
- Alpha
- Beta
- Gamma
Radioactive 
contaminants can 
be dispersed using 
sprayers/aerosol 
generators, or by 
point or line 
sources such as 
munitions, covert 
deposits, and 
moving sprayers. 
Contaminants 
may remain 
hazardous for 
seconds to years, 
depending on 
material used. 
Initial effects will be 
localized to site of 
attack; depending 
on meteorological 
conditions, 
subsequent behavior 
of radioactive 
contaminants may 
be dynamic. 
Duration of exposure, 
distance from source 
of radiation, and the 
amount of shielding 
between source and 
target determine 
exposure to radiation. 
Nuclear Device
Detonation of 
nuclear device 
underground, at the 
surface, in the air or 
at high altitude. 
Light/heat flash 
and blast/shock 
wave last for 
seconds; nuclear 
radiation and 
fallout hazards 
can persist for 
years. 
Electromagnetic 
pulse from a 
high-altitude 
detonation lasts 
for seconds and 
affects 
unprotected 
electronic 
systems. 
Initial light, heat, 
and blast effects of a 
subsurface, ground, 
or air burst are static 
and are determined 
by the devices 
characteristics and 
employment; fallout 
of radioactive 
contaminants may 
be dynamic, 
depending on 
meteorological 
conditions. 
Harmful effects of 
radiation can be 
reduced by 
minimizing the time 
of exposure. Light, 
heat, and blast energy 
decrease 
logarithmically as a 
function of distance 
from seat of blast. 
Terrain, forestation, 
structures, etc., can 
provide shielding by 
absorbing and/or 
deflecting blast, 
radiation, and 
radioactive 
contaminants. 


Table 1-3: Event Profiles for Terrorism and Technological Hazards* (continued



Threat/Hazard
Application 
Mode
Duratio
n
Extent of 
Effects;Static/Dynamic
Mitigating and 
Exacerbating Conditions

Hazardous Material 
Release
(fixed site or 
transportation)
- Toxic 
Industrial 
Chemicals and 
Materials 
(Organic 
vapors: 
cyclohexane; 
Acid gases: 
cyanogens, 
chlorine, 
hydrogen 
sulfide; Base 
gases: 
ammonia; 
Special cases: 
phosgene, 
formaldehyde)
Solid, liquid, 
and/or gaseous 
contaminants 
may be released 
from fixed or 
mobile 
containers.
Hours to 
days.
Chemicals may be 
corrosive or 
otherwise damaging 
over time. 
Explosion and/or 
fire may be 
subsequent. 
Contamination may 
be carried out of 
the incident area by 
persons, vehicles, 
water, and wind.
As with chemical weapons, 
weather conditions will 
directly affect how the hazard 
develops. The micro-
meteorological effects of 
buildings and terrain can alter 
travel and duration of agents. 
Shielding in the form of 
sheltering in place may 
protect people and property 
from harmful effects. Non-
compliance with fire and 
building codes as well as 
failure to maintain existing 
fire protection and 
containment features can 
substantially increase the 
damage from a hazardous 
materials release. 
Unauthorized 
Entry
- Forced
- Covert
Use of hand or 
power tools, 
weapons, or 
explosives to 
create a man-
sized opening or 
operate an 
assembly (such 
as a locked 
door), or use of 
false credentials 
to enter a 
building.
Minutes to 
hours, 
depending 
upon the 
intent. 
If goal is to steal or 
destroy physical 
assets or 
compromise 
information, the 
initial effects are 
quick, but damage 
may be long 
lasting. If intent is 
to disrupt 
operations or take 
hostages, the effects 
may last for a long 
time, especially if 
injury or death 
occurs.
Standard physical security 
building design should be the 
minimum mitigation 
measure. For more critical 
assets, additional measures, 
like closed circuit television 
or traffic flow that channels 
visitors past access control, 
aids in detection of this 
hazard.


Table 1-3: Event Profiles for Terrorism and Technological Hazards* (continued



Threat/Hazard
Application 
Mode
Duratio
n
Extent of 
Effects;Static/Dynamic
Mitigating and 
Exacerbating Conditions


Surveillance
- Acoustic
- Electronic 
eavesdrop
ping
- Visual
Stand-off collection of 
visual information using 
cameras or high powered 
optics, acoustic 
information using 
directional microphones 
and lasers, and electronic 
information from 
computers, cell phones, 
and hand-held radios. 
Placed collection by 
putting a device "bug" at 
the point of use.
Usually 
months.
This is usually the prelude 
to the loss of an asset. A 
terrorist surveillance team 
spends much time looking 
for vulnerabilities and 
tactics that will be 
successful. This is the time 
period that provides the 
best assessment of threat 
because it indicates 
targeting of the building.
Building design, 
especially blocking 
lines of sight and 
ensuring the exterior 
walls and windows 
do not allow sound 
transmission or 
acoustic collection, 
can mitigate this 
hazard.


* SOURCE: FEMA 386-7, INTEGRATING HUMAN-CAUSED HAZARDS INTO MITIGATION PLANNING, SEPTEMBER 200


  


Figure 1-8 Facility system interaction


Table 1-4: Homeland Security Threat Condition



Threat Level
Threat Analysis Factors

Existence
Capability
History
Intention
s
Targetin
g
Severe (Red)
_
_
_
_
_
High (Orange)
_
_
_
_
_
Elevated (Yellow)
_
_
_
_

Guarded (Blue)
_
_
_


Low (Green)
_
_





_ Factor must be present            _	Factor may or may not be presen


Please note the DHS does not use these threat analysis factors to determine threat level. 
SOURCE: COMMONWEALTH OF KENTUCKY OFFICE OF HOMELAND SECURIT


Table 1-5: Site/Building Inherent Vulnerability Assessment Matrix (Partial Risk Assessment)*

Criteria
0
1
2
3
4
5
Score
Asset Visibility

Existence 
not well 
known

Existence 
locally 
known

Existence 
widely 
known

Target Utility
None
Very Low
Low
Medium
High
Very High

Asset Accessibility
Remote 
location, 
secure 
perimeter, 
armed 
guards, 
tightly 
controlled 
access
Fenced, 
guarded, 
controlled 
access
Controlled 
access, 
protected 
entry
Controlled 
access, 
unprotected 
entry
Open access, 
restricted 
parking
Open 
access, 
unrestricted 
parking

Asset Mobility

Moves or is 
relocated 
frequently

Moves or is 
relocated 
occasionall
y

Permanent/ 
fixed in 
place

Presence of 
Hazardous Materials
No 
hazardous 
materials 
present
Limited 
quantities, 
materials in 
secure 
location
Moderate 
quantities, 
strict 
control 
features
Large 
quantities, 
some 
control 
features
Large 
quantities, 
minimal 
control 
features
Large 
quantities, 
accessible 
to non-staff 
personnel

Collateral Damage 
Potential
No risk
Low 
risk/limite
d to 
immediate 
area
Moderate 
risk/limite
d to 
immediate 
area
Moderate 
risk within 
1-mile 
radius
High risk 
within 1-
mile radius
High risk 
beyond 1-
mile radius

Site 
Population/Capacity
0
1-250
251-500
501-1,000
1,001-5,000
> 5,000







Total



* SOURCE: FEMA 386-7, INTEGRATING HUMAN-CAUSED HAZARDS INTO MITIGATION PLANNING, SEPTEMBER 200


Table 1-6: Classification Table Extracts


Table 1-7: Selected Extracts -- Recommended Standards Chart


M   Minimum Standard    S   Standard Based On Facility EvaluationD   Desirable (to minimize risk)              
N/A  Not Applicabl


Table 1-7: Selected Extracts -- Recommended Standards Chart* (continued


M   Minimum Standard    S   Standard Based On Facility EvaluationD   Desirable (to minimize risk)             
N/A  Not Applicabl




LEVEL

I
I
I
II
I
I
V
V


Table 1-8: Level of Visibility


Rating Value
Invisible  Classified location
0
Very Low Visibility  Probably not aware of 
existence
1
Low Visibility  Existence probably not well known
2
Medium Visibility  Existence is probably known
3
High Visibility  Existence is well known
4
Very High Visibility  Existence is obvious
5


Table 1-9: Criticality of Target Site


Rating Value
No Usefulness
0
Minor Usefulness
1
Moderate Usefulness
2
Significant Usefulness
3
Highly Useful
4
Critical
5


Table 1-10: Target Value to Potential Threat Element


Rating Value
None
0
Very Low
1
Low
2
Medium
3
High
4
Very 
High
5


Table 1-11: Aggressor Access to Target


Rating 
Value
Fenced, Guarded, Protected Air/Consumable Entry, Controlled Access by Pass Only, No Vehicle 
Parking within a designated minimum distance (such as 50 feet or 80 feet)
0
Guarded, Protected Air/Consumable Entry, Controlled Access of Visitors and Non-Staff 
Personnel, No Vehicle Parking within the designated minimum distance
1
Protected Air/Consumable Entry, Controlled Access of Visitors and Non-Staff Personnel, No 
Unauthorized Vehicle Parking within the designated minimum distance
2
Controlled Access of Visitors, Unprotected Air/Consumable Entry, No Unauthorized Vehicle 
Parking within the designated minimum distance
3
Open Access to All Personnel, Unprotected Air/Consumable Entry, No Unauthorized Vehicle 
Parking within the designated minimum distance
4
Open Access to All Personnel, Unprotected Air/Consumable Entry, Vehicle Parking within the 
designated minimum distance
5


Table 1-12: Target Threat of Hazard (WMD Materials)


Rating 
Value
No CBR materials present
0
CBR materials present in moderate quantities, under positive control, and in secured locations
1
CBR materials present in moderate quantities and controlled
2
Major concentrations of CBR materials that have established control features and are secured in 
the site
3
Major concentrations of CBR materials that have moderate control features
4
Major concentrations of CBR materials that are accessible to non-staff personnel
5


Table 1-17: Simplified Building Ranking Matrix

Building
Criticality of 
Function
Location
Occupancy of 
Building
Involvement in 
Community
Critical External 
Commitments
Total 
Score
Headquarters
2
5
3
1
4
15
Hospital 1
1
2
2
1
1
7
Hospital 2
3
2
3
4
4
16
Data Center
5
4
3
3
2
17


Figure 1-9 Common system vulnerabilitie


Table 1-20: Site Functional Pre-Assessment Screening Matrix*

Function
Cyber Attack
Armed Attack (single gunman)
Vehicle Bomb
CBR Attack
Administration
280
140
135
90
Asset Value
5
5
5
5
Threat Rating
8
4
3
2
Vulnerability 
Rating
7
7
9
9
Engineering 
128
128
192
144
Asset Value
8
8
8
8
Threat Rating
8
4
3
2
Vulnerability 
Rating
2
4
8
9
Warehousing
96
36

54
Asset Value
3
3
3
3
Threat Rating
8
4
3
2
Vulnerability 
Rating
4
3
9
9
Data Center
360
128
216
144
Asset Value
8
8
8
8
Threat Rating
9
4
3
2
Vulnerability 
Rating
5
4
9
9
Food Service
2
32
48
36
Asset Value
2
2
2
2
Threat Rating
1
4
3
2
Vulnerability 
Rating
1
4
8
9
Security
280
140
168
126
Asset Value
7
7
7
7
Threat Rating
8
4
3
2
Vulnerability 
Rating
5
5
8
9
Housekeeping
16
64
48
36
Asset Value
2
2
2
2
Threat Rating
8
4
3
2
Vulnerability 
Rating
1
8
8
9
Day Care
54
324
243
162
Asset Value
9
9
9
9
Threat Rating
3
4
3
2
Vulnerability 
Rating
2
9
9
9

    * NOTIONAL DATA INSERTED FOR DEMONSTRATION PURPOSES


Table 1-20: Site Functional Pre-Assessment Screening Matrix* (continued



 Function
Cyber Attack
Armed Attack (single gunman)
Vehicle Bomb
CBR Attack


Table 1-21: Site Infrastructure Systems Pre-Assessment Screening Matrix* (continued



Functio
n
Cyber Attack
Armed Attack (single gunman)
Vehicle Bomb
CBR Attack


Figure 1-10 Non-redundant critical functions collocated near loading doc


Figure 1-11 Vulnerability example


Figure 1-12 Typical building design and construction proces


Figure 1-13 Risk management choice


Table 1-22: Building Vulnerablilty Assessment Checklist



Section
Vulnerability Question
Guidance
Observations


1         Sit

1.


What major structures surround the facility (site or building(s))?
What critical infrastructure, government, military, or recreation facilities are in the local area that impact 
transportation, utilities, and collateral damage (attack at this facility impacting the other major structures 
or attack on the major structures impacting this facility)?
What are the adjacent land uses immediately outside the perimeter of this facility (site or building(s))?
Do future development plans change these land uses outside the facility (site or building (s)) perimeter? 
Although this question bridges threat and vulnerability, the threat is the manmade hazard that can occur 
(likelihood and impact) and the vulnerability is the proximity of the hazard to the building(s) being 
assessed. Thus, a chemical plant release may be a threat/hazard, but vulnerability changes if the plant is 1 
mile upwind for the prevailing winds versus 10 miles away and downwind. Similarly, a terrorist attack upon 
an adjacent building may impact the building(s) being assessed. The Murrah Federal Building in Oklahoma 
City was not the only building to have severe damage caused by the explosion of the Ryder rental truck 
bomb


Critical infrastructure to consider includes:
Telecommunications infrastructure
Facilities for broadcast TV, cable TV; cellular networks; newspaper offices, production, and distribution; 
radio stations; satellite base stations; telephone trunking and switching stations, including critical cable 
routes and major rights-of-way
Electric power systems
Power plants, especially nuclear facilities; transmission and distribution system components; fuel distribution, 
delivery, and storage
Gas and oil facilities
Hazardous material facilities, oil/gas pipelines, and storage facilitie


Banking and finance institutions
Financial institutions (banks, credit unions) and the business district; note schedule business/financial district 
may follow; armored car services
Transportation networks
Airports: carriers, flight paths, and airport layout; location of air traffic control towers, runways, passenger 
terminals, and parking areas
Bus Stations
Pipelines: oil; gas
Trains/Subways: rails and lines, railheads/rail yards, interchanges, tunnels, and cargo/passenger terminals; note 
hazardous material transported
Traffic: interstate highways/roads/tunnels/bridges carrying large volumes; points of congestion; note time of day 
and day of week
Trucking: hazardous materials cargo loading/unloading facilities; truck terminals, weigh stations, and rest areas
Waterways: dams; levees; berths and ports for cruise ships, ferries, roll-on/roll-off cargo vessels, and container 
ships; international (foreign) flagged vessels (and cargo)
Water supply systems
Pipelines and process/treatment facilities, dams for water collection; wastewater treatment 
Government services
Federal/state/local government offices  post offices, law enforcement stations, fire/rescue, town/city hall, 
local mayors/governors residences, judicial offices and courts, military installations (include type-Active, 
Reserves, National Guard)
Emergency services
Backup facilities, communications centers, Emergency Operations Centers (EOCs), fire/Emergency Medical Service 
(EMS) facilities, Emergency Medical Center (EMCs), law enforcement facilities
The following are not critical infrastructure, but have potential collateral damage to consider: 
Agricultural facilities: chemical distribution, storage, and application sites; crop spraying services; farms and 
ranches; food processing, storage, and distribution facilities
Commercial/manufacturing/industrial facilities: apartment buildings; business/corporate centers; chemical 
plants (especially those with Section 302 Extremely Hazardous Substances); factories; fuel production, 
distribution, and storage facilities; hotels and convention centers; industrial plants; raw material production, 
distribution, and storage facilities; research facilities and laboratories; shipping, warehousing, transfer, and 
logistical centers
Events and attractions: festivals and celebrations; open-air markets; parades; rallies, demonstrations, and 
marches; religious services; scenic tours; theme parks
Health care system components: family planning clinics; health department offices; hospitals; radiological 
material and medical waste transportation, storage, and disposal; research facilities and laboratories, walk-in 
clinics
Political or symbolically significant sites: embassies, consulates, landmarks, monuments, political party and 
special interest groups offices, religious sites
Public/private institutions: academic institutions, cultural centers, libraries, museums, research facilities and 
laboratories, schools
Recreation facilities: auditoriums, casinos, concert halls and pavilions, parks, restaurants and clubs (frequented 
by potential target populations), sports arenas, stadiums, theaters, malls, and special interest group facilities; note 
congestion dates and times for shopping centers
References: FEMA 386-7, FEMA SLG 101, DOJ NCJ181200



1.2
Does the terrain place the building in a depression or low area?

Depressions or low areas can trap heavy vapors, inhibit natural decontamination by prevailing winds, and reduce 
the effectiveness of in-place sheltering.
Reference: USAF Installation Force Protection Guid



1.3

In dense, urban areas, does curb lane parking allow uncontrolled vehicles to park unacceptably close to a 
building in public rights-of-way


Where distance from the building to the nearest curb provides insufficient setback, restrict parking in the curb lane. 
For typical city streets, this may require negotiating to close the curb lane. Setback is common terminology for the 
distance between a building and its associated roadway or parking. It is analogous to stand-off between a vehicle 
bomb and the building. The benefit per foot of increased stand-off between a potential vehicle bomb and a 
building is very high when close to a building and decreases rapidly as the distance increases. Note that the July 1, 
1994, Americans with Disabilities Act Standards for Accessible Design states that required handicapped parking shall 
be located on the shortest accessible route of travel from adjacent parking to an accessible entrance.
Reference: GSA PBS-P100

1.4

Is a perimeter fence or other types of barrier controls in place?
The intent is to channel pedestrian traffic onto a site with multiple buildings through known access control points. 
For a single building, the intent is to have a single visitor entrance.
Reference: GSA PBS-P100 
1.5

What are the site access points to the site or building?

The goal is to have at least two access points  one for passenger vehicles and one for delivery trucks due to the 
different procedures needed for each. Having two access points also helps if one of the access points becomes 
unusable, then traffic can be routed through the other access point.
Reference: USAF Installation Force Protection Guide

1.6

Is vehicle traffic separated from pedestrian traffic on the site?
Pedestrian access should not be endangered by car traffic. Pedestrian access, especially from public transportation, 
should not cross vehicle traffic if possible.
References: GSA PBS-P100 and FEMA 386-7

1.7
Is there vehicle and pedestrian access control at the perimeter of the site



Vehicle and pedestrian access control and inspection should occur as far from facilities as possible (preferably at the 
site perimeter) with the ability to regulate the flow of people and vehicles one at a time.
Control on-site parking with identification checks, security personnel, and access control systems.
Reference: FEMA 386-7
1.8
Is there space for inspection at the curb line or outside the protected perimeter?
What is the minimum distance from the inspection location to the building



Design features for the vehicular inspection point include: vehicle arrest devices that prevent vehicles from leaving 
the vehicular inspection area and prevent tailgating.
If screening space cannot be provided, consider other design features such as: hardening and alternative location for 
vehicle search/inspection.
Reference: GSA PBS-P100   

1.9
Is there any potential access to the site or building through utility paths or water runoff




Eliminate potential site access through utility tunnels, corridors, manholes, stormwater runoff culverts, etc. Ensure 
covers to these access points are secured.
Reference: USAF Installation Force Protection Guide

1.10
What are the existing types of vehicle anti-ram devices for the site or building?
Are these devices at the property boundary or at the building



Passive barriers include bollards, walls, hardened fences (steel cable interlaced), trenches, ponds/basins, concrete 
planters, street furniture, plantings, trees, sculptures, and fountains. Active barriers include pop-up bollards, swing 
arm gates, and rotating plates and drums, etc.
Reference: GSA PBS-P100

1.11
What is the anti-ram buffer zone stand-off distance from the building to unscreened vehicles or parking



If the recommended distance for the postulated threat is not available, consider reducing the stand-off required 
through structural hardening or manufacturing additional stand-off through barriers and parking restrictions. Also, 
consider relocation of vulnerable functions within the building, or to a more hazard-resistant building. More stand-
off should be used for unscreened vehicles than for screened vehicles that have been searched.
Reference: GSA PBS-P100
1.12
Are perimeter barriers capable of stopping vehicles?
Will the vehicle barriers at the perimeter and building maintain access for emergency responders, 
including large fire apparatus


Anti-ram protection may be provided by adequately designed: bollards, street furniture, sculpture, landscaping, 
walls, and fences. The anti-ram protection must be able to stop the threat vehicle size (weight) at the speed 
attainable by that vehicle at impact. If the anti-ram protection cannot absorb the desired kinetic energy, consider 
adding speed controls (serpentines or speed bumps) to limit the speed at impact. If the resultant speed is still too 
great, the anti-ram protection should be improved.
References: Military Handbook 1013/14 and GSA PBS P-100



1.13
Does site circulation prevent high-speed approaches by vehicles



The intent is to use site circulation to minimize vehicle speeds and eliminate direct approaches to structures.
Reference: GSA PBS-P100



1.14
Are there offsetting vehicle entrances from the direction of a vehicles approach to force a reduction of 
speed



Single or double 90-degree turns effectively reduce vehicle approach speed.
Reference: GSA PBS-P100
1.1


Is there a minimum setback distance between the building and parked vehicles

Adjacent public parking should be directed to more distant or better-protected areas, segregated from employee 
parking and away from the building. Some publications use the term setback in lieu of the term stand-off.
Reference: GSA PBS-P100

1.1


Does adjacent surface parking on site maintain a minimum stand-off distance





The specific stand-off distance needed is based upon the design basis threat bomb size and the building 
construction. For initial screening, consider using 25 meters (82 feet) as a minimum, with more distance needed for 
unreinforced masonry or wooden walls.
Reference: GSA PBS-P100

1.1


Do standalone, aboveground parking garages provide adequate visibility across as well as into and out of 
the parking garage


Pedestrian paths should be planned to concentrate activity to the extent possible.
Limiting vehicular entry/exits to a minimum number of locations is beneficial.
Stair tower and elevator lobby design should be as open as code permits. Stair and/or elevator waiting areas should 
be as open to the exterior and/or the parking areas as possible and well lighted. Impact-resistant, laminated glass for 
stair towers and elevators is a way to provide visual openness.
Potential hiding places below stairs should be closed off; nooks and crannies should be avoided, and dead-end 
parking areas should be eliminated.
Reference: GSA PBS-P100

1.1


Are garage or service area entrances for employee-permitted vehicles protected by suitable anti-ram devices?
Coordinate this protection with other anti-ram devices, such as on the perimeter or property boundary to 
avoid duplication of arresting capability


Control internal building parking, underground parking garages, and access to service areas and loading docks in this 
manner with proper access control, or eliminate the parking altogether.
The anti-ram device must be capable of arresting a vehicle of the designated threat size at the speed attainable at the 
location.
Reference: GSA PBS-P100

1.1


Do site landscaping and street furniture provide hiding places



Minimize concealment opportunities by keeping landscape plantings (hedges, shrubbery, and large plants with 
heavy ground cover) and street furniture (bus shelters, benches, trash receptacles, mailboxes, newspaper vending 
machines) away from the building to permit observation of intruders and prevent hiding of packages.
If mail or express boxes are used, the size of the openings should be restricted to prohibit the insertion of packages.
Reference: GSA PBS-P100
1.2


Is the site lighting adequate from a security perspective in roadway access and parking areas


Security protection can be successfully addressed through adequate lighting. The type and design of lighting, 
including illumination levels, is critical. Illuminating Engineering Society of North America (IESNA) guidelines can be 
used. The site lighting should be coordinated with the CCTV system.
Reference: GSA PBS-P100
1.2


Are line-of-sight perspectives from outside the secured boundary to the building and on the property 
along pedestrian and vehicle routes integrated with landscaping and green space


The goal is to prevent the observation of critical assets by persons outside the secure boundary of the site. For 
individual buildings in an urban environment, this could mean appropriate window treatments or no windows for 
portions of the building.
Once on the site, the concern is to ensure observation by a general workforce aware of any pedestrians or vehicles 
outside normal circulation routes or attempting to approach the building unobserved.
Reference: USAF Installation Force Protection Guide
1.22
Do signs provide control of vehicles and people



The signage should be simple and have the necessary level of clarity. However, signs that identify sensitive areas 
should generally not be provided.
Reference: GSA PBS-P100

1.23
Are all existing fire hydrants on the site accessible


Just as vehicle access points to the site must be able to transit emergency vehicles, so too must the emergency 
vehicles have access to the buildings and, in the case of fire trucks, the fire hydrants. Thus, security considerations 
must accommodate emergency response requirements.
Reference: GSA PBS-P100












2         Architectural


2.1

Does the site and architectural design incorporate strategies from a Crime Prevention Through 
Environmental Design (CPTED) perspective




The focus of CPTED is on creating defensible space by employing:
1. Natural access controls:
  Design streets, sidewalks, and building entrances to clearly indicate public routes and direct people away from 
private/restricted areas
  Discourage access to private areas with structural elements and limit access (no cut-through streets)
  Loading zones should be separate from public parking
2. Natural surveillance:
  Design that maximizes visibility of people, parking areas, and building entrances; doors and windows that look 
out on to streets and parking areas
  Shrubbery under 2 feet in height for visibility
  Lower branches of existing trees kept at least 10 feet off the ground
  Pedestrian-friendly sidewalks and streets to control pedestrian and vehicle circulation
  Adequate nighttime lighting, especially at exterior doorways
3. Territorial reinforcement:
  Design that defines property lines
  Design that distinguishes private/restricted spaces from public spaces using separation, landscape plantings; 
pavement designs (pathway and roadway placement); gateway treatments at lobbies, corridors, and door 
placement; walls, barriers, signage, lighting, and "CPTED" fences
  "Traffic-calming" devices for vehicle speed control
4. Target hardening:
  Prohibit entry or access: window locks, deadbolts for doors, interior door hinges
  Access control (building and employee/visitor parking) and intrusion detection systems
5. Closed circuit television cameras:
  Prevent crime and influence positive behavior, while enhancing the intended uses of space. In other words, 
design that eliminates or reduces criminal behavior and at the same time encourages people to "keep an eye out" 
for each other.
References: GSA PBS-P100 and FEMA 386-7

2.


Is it a mixed-tenant building


Separate high-risk tenants from low-risk tenants and from publicly accessible areas. Mixed uses may be 
accommodated through such means as separating entryways, controlling access, and hardening shared partitions, as 
well as through special security operational countermeasures.
Reference: GSA PBS-P100

2.


Are pedestrian paths planned to concentrate activity to aid in detectio


Site planning and landscape design can provide natural surveillance by concentrating pedestrian activity, limiting 
entrances/exits, and eliminating concealment opportunities. Also, prevent pedestrian access to parking areas other 
than via established entrances.
Reference: GSA PBS-P100
2.


Are there trash receptacles and mailboxes in close proximity to the building that can be used to hide 
explosive devices


The size of the trash receptacles and mailbox openings should be restricted to prohibit insertion of packages. Street 
furniture, such as newspaper vending machines, should be kept sufficient distance (10 meters or 33 feet) from the 
building, or brought inside to a secure area.
References: USAF Installation Force Protection Guide and DoD UCF 4-010-01

2.


Do entrances avoid significant queuing



If queuing will occur within the building footprint, the area should be enclosed in blast-resistant construction. If 
queuing is expected outside the building, a rain cover should be provided. For manpower and equipment 
requirements, collocate or combine staff and visitor entrances.
Reference: GSA PBS-P100

2.


Does security screening cover all public and private areas?
Are public and private activities separated?
Are public toilets, service spaces, or access to stairs or elevators located in any non-secure areas, including 
the queuing area before screening at the public entrance


Retail activities should be prohibited in non-secured areas. However, the Public Building Cooperative Use Act of 
1976 encourages retail and mixed uses to create open and inviting buildings. Consider separating entryways, 
controlling access, hardening shared partitions, and special security operational countermeasures.
References: GSA PBS-P100 and FEMA 386-7


2.


Is access control provided through main entrance points for employees and visitors?
(lobby receptionist, sign-in, staff escorts, issue of visitor badges, checking forms of personal identification, electronic 
access control systems


Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities


2.


Is access to private and public space or restricted area space clearly defined through the design of the space, 
signage, use of electronic security devices, etc.



Finishes and signage should be designed for visual simplicity.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
2.


Is access to elevators distinguished as to those that are designated only for employees and visitors



Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

2.1


Do public and employee entrances include space for possible future installation of access control and 
screening equipment


These include walk-through metal detectors and x-ray devices, identification check, electronic access card, search 
stations, and turnstiles.
Reference: GSA PBS-P100

2.1


Do foyers have reinforced concrete walls and offset interior and exterior doors from each other


Consider for exterior entrances to the building or to access critical areas within the building if explosive blast hazard 
must be mitigated.
Reference: U.S. Army TM 5-853 
2.1


Do doors and walls along the line of security screening meet requirements of UL752 "Standard for Safety: 
Bullet-Resisting Equipment"



If the postulated threat in designing entrance access control includes rifles, pistols, or shotguns, then the screening 
area should have bullet-resistance to protect security personnel and uninvolved bystanders. Glass, if present, should 
also be bullet-resistant.
Reference: GSA PBS-P100

2.1


Do circulation routes have unobstructed views of people approaching controlled access points



This applies to building entrances and to critical areas within the building.
References: USAF Installation Force Protection Guide and DoD UFC 4-010-01
2.1


Is roof access limited to authorized personnel by means of locking mechanisms



References: GSA PBS-P100 and CDC/NIOSH, Pub 2002-139
2.1


Are critical assets (people, activities, building systems and components) located close to any main entrance, 
vehicle circulation, parking, maintenance area, loading dock, or interior parking?
Are the critical building systems and components hardened


Critical building components include: Emergency generator including fuel systems, day tank, fire sprinkler, and 
water supply; Normal fuel storage; Main switchgear; Telephone distribution and main switchgear; Fire pumps; 
Building control centers; Uninterruptible Power Supply (UPS) systems controlling critical functions; Main 
refrigeration and ventilation systems if critical to building operation; Elevator machinery and controls; Shafts for 
stairs, elevators, and utilities; Critical distribution feeders for emergency power. Evacuation and rescue require 
emergency systems to remain operational during a disaster and they should be located away from potential attack 
locations. Primary and backup systems should be separated to reduce the risk of both being impacted by a single 
incident if collocated. Utility systems should be located at least 50 feet from loading docks, front entrances, and 
parking areas.
One way to harden critical building systems and components is to enclose them within hardened walls, floors, and 
ceilings. Do not place them near high-risk areas where they can receive collateral damage.
Reference: GSA PBS-P100

2.1


Are high-value or critical assets located as far into the interior of the building as possible and separated 
from the public areas of the building



Critical assets, such as people and activities, are more vulnerable to hazards when on an exterior building wall or 
adjacent to uncontrolled public areas inside the building.
Reference: GSA PBS-P100
2.1


Is high visitor activity away from critical assets



High-risk activities should also be separated from low-risk activities. Also, visitor activities should be separated from 
daily activities.
Reference: USAF Installation Force Protection Guide
2.1


Are critical assets located in spaces that are occupied 24 hours per day?
Are assets located in areas where they are visible to more than one person


Reference: USAF Installation Force Protection Guide


2.1


Are loading docks and receiving and shipping areas separated in any direction from utility rooms, utility 
mains, and service entrances, including electrical, telephone/data, fire detection/alarm systems, fire 
suppression water mains, cooling and heating mains, etc.



Loading docks should be designed to keep vehicles from driving into or parking under the building. If loading docks 
are in close proximity to critical equipment, consider hardening the equipment and service against explosive blast. 
Consider a 50-foot separation distance in all directions.
Reference: GSA PBS-P100
2.20
Are mailrooms located away from building main entrances, areas containing critical services, utilities, 
distribution systems, and important assets?
Is the mailroom located near the loading dock?

The mailroom should be located at the perimeter of the building with an outside wall or window designed for 
pressure relief.
By separating the mailroom and the loading dock, the collateral damage of an incident at one has less impact upon 
the other. However, this may be the preferred mailroom location.
Off-site screening stations or a separate delivery processing building on site may be cost-effective, particularly if 
several buildings may share one mailroom. A separate delivery processing building reduces risk and simplifies 
protection measures.
Reference: GSA PBS-P100


2.21
Does the mailroom have adequate space available for equipment to examine incoming packages and for an 
explosive disposal container





Screening of all deliveries to the building, including U.S. mail, commercial package delivery services, delivery of office 
supplies, etc.
Reference: GSA PBS-P100
2.2


Are areas of refuge identified, with special consideration given to egress


Areas of refuge can be safe havens, shelters, or protected spaces for use during specified hazards.
Reference: FEMA 386-7


2.23
Are stairwells required for emergency egress located as remotely as possible from high-risk areas where 
blast events might occur?
Are stairways maintained with positive pressure or are there other smoke control systems



Consider designing stairs so that they discharge into areas other than lobbies, parking, or loading docks.
Maintaining positive pressure from a clean source of air (may require special filtering) aids in egress by keeping 
smoke, heat, toxic fumes, etc,. out of the stairway. Pressurize exit stairways in accordance with the National Model 
Building Code.
References: GSA PBS-P100 and CDC/NIOSH, Pub 2002-139


2.2


Are enclosures for emergency egress hardened to limit the extent of debris that might otherwise impede 
safe passage and reduce the flow of evacuees?


Egress pathways should be hardened and discharge into safe areas.
Reference: FEMA 386-7
2.2


Do interior barriers differentiate level of security within a building


Reference: USAF Installation Force Protection Guide

2.2


Are emergency systems located away from high-risk areas



The intent is to keep the emergency systems out of harms way, such that one incident does not take out all 
capability  both the regular systems and their backups.
Reference: FEMA 386-7

2.2

Is interior glazing near high-risk areas minimized?
Is interior glazing in other areas shatter-resistant



Interior glazing should be minimized where a threat exists and should be avoided in enclosures of critical functions 
next to high-risk areas.
Reference: GSA PBS-P100

2.2


Are ceiling and lighting systems designed to remain in place during hazard events?

When an explosive blast shatters a window, the blast wave enters the interior space, putting structural and non-
structural building components under loads not considered in standard building codes. It has been shown that 
connection criteria for these systems in high seismic activity areas resulted in much less falling debris that could injure 
building occupants.
Mount all overhead utilities and other fixtures weighing 14 kilograms (31 pounds) or more to minimize the 
likelihood that they will fall and injure building occupants. Design all equipment mountings to resist forces of 0.5 
times the equipment weight in any direction and 1.5 times the equipment weight in the downward direction. This 
standard does not preclude the need to design equipment mountings for forces required by other criteria, such as 
seismic standards.
Reference: DoD UCF 4-101-0




3         Structural Systems


3.


What type of construction?
What type of concrete and reinforcing steel?
What type of steel?
What type of foundation?


The type of construction provides an indication of the robustness to abnormal loading and load reversals. A 
reinforced concrete moment-resisting frame provides greater ductility and redundancy than a flat-slab or flat-plate 
construction. The ductility of steel frame with metal deck depends on the connection details and pre-tensioned or 
post-tensioned construction provides little capacity for abnormal loading patterns and load reversals. The resistance 
of load-bearing wall structures varies to a great extent, depending on whether the walls are reinforced or un-
reinforced. A rapid screening process developed by FEMA for assessing structural hazards identifies the following 
types of construction with a structural score ranging from 1.0 to 8.5. A higher score indicates a greater capacity to 
sustain load reversals.
Wood buildings of all types - 4.5 to 8.5
Steel moment-resisting frames - 3.5 to 4.5
Braced steel frames - 2.5 to 3.0
Light metal buildings - 5.5 to 6.5
Steel frames with cast-in-place concrete shear walls - 3.5 to 4.5
Steel frames with unreinforced masonry infill walls - 1.5 to 3.0
Concrete moment-resisting frames - 2.0 to 4.0
Concrete shear wall buildings - 3.0 to 4.0
Concrete frames with unreinforced masonry infill walls - 1.5 to 3.0
Tilt-up buildings - 2.0 to 3.5
Precast concrete frame buildings - 1.5 to 2.5
Reinforced masonry - 3.0 to 4.0
Unreinforced masonry - 1.0 to 2.5
References: FEMA 154 and Physical Security Assessment for the Department of Veterans Affairs Facilities
3.2
Do the reinforced concrete structures contain symmetric steel reinforcement (positive and negative faces) 
in all floor slabs, roof slabs, walls, beams, and girders that may be subjected to rebound, uplift, and 
suction pressures?
Do the lap splices fully develop the capacity of the reinforcement?
Are lap splices and other discontinuities staggered?
Do the connections possess ductile details?
Is special shear reinforcement, including ties and stirrups, available to allow large post-elastic behavior?

Reference: GSA PBS-P100

3.3
Are the steel frame connections moment connections?
Is the column spacing minimized so that reasonably sized members will resist the design loads and 
increase the redundancy of the system?
What are the floor-to-floor heights?

A practical upper level for column spacing is generally 30 feet. Unless there is an overriding architectural 
requirement, a practical limit for floor-to-floor heights is generally less than or equal to 16 feet.
Reference: GSA PBS-P100
3.4
Are critical elements vulnerable to failure?
The priority for upgrades should be based on the relative importance of structural or non-structural elements that 
are essential to mitigating the extent of collapse and minimizing injury and damage.
Primary Structural Elements provide the essential parts of the buildings resistance to catastrophic blast loads and 
progressive collapse. These include columns, girders, roof beams, and the main lateral resistance system.
Secondary Structural Elements consist of all other load-bearing members, such as floor beams, slabs, etc.
Primary Non-Structural Elements consist of elements (including their attachments) that are essential for life safety 
systems or elements that can cause substantial injury if failure occurs, including ceilings or heavy suspended 
mechanical units.
Secondary Non-Structural Elements consist of all elements not covered in primary non-structural elements, such as 
partitions, furniture, and light fixtures.
Reference: GSA PBS-P100

3.5
Will the structure suffer an unacceptable level of damage resulting from the postulated threat (blast 
loading or weapon impact)?  

The extent of damage to the structure and exterior wall systems from the bomb threat may be related to a 
protection level. The following is for new buildings: 
Level of Protection Below Antiterrorism Standards  Severe damage. Frame collapse/massive destruction. Little 
left standing. Doors and windows fail and result in lethal hazards. Majority of personnel suffer fatalities.
Very Low Level Protection  Heavy damage. Onset of structural collapse. Major deformation of primary and 
secondary structural members, but progressive collapse is unlikely. Collapse of non-structural elements. Glazing will 
break and is likely to be propelled into the building, resulting in serious glazing fragment injuries, but fragments will 
be reduced. Doors may be propelled into rooms, presenting serious hazards. Majority of personnel suffer serious 
injuries. There are likely to be a limited number (10 percent to 25 percent) of fatalities.
Low Level of Protection  Moderate damage, unrepairable. Major deformation of non-structural elements and 
secondary structural members and minor deformation of primary structural members, but progressive collapse is 
unlikely. Glazing will break, but fall within 1 meter of the wall or otherwise not present a significant fragment 
hazard. Doors may fail, but they will rebound out of their frames, presenting minimal hazards. Majority of personnel 
suffer significant injuries. There may be a few (<10 percent) fatalities.
Medium Level Protection  Minor damage, repairable. Minor deformations of non-structural elements and 
secondary structural members and no permanent deformation in primary structural members. Glazing will break, 
but will remain in the window frame. Doors will stay in frames, but will not be reusable. Some minor injuries, but 
fatalities are unlikely.
High Level Protection  Minimal damage, repairable. No permanent deformation of primary and secondary 
structural members or non-structural elements. Glazing will not break. Doors will be reusable. Only superficial 
injuries are likely.
Reference: DoD UFC 4-010-01

3.6
Is the structure vulnerable to progressive collapse?
Is the building capable of sustaining the removal of a column for one floor above grade at the building 
perimeter without progressive collapse?
In the event of an internal explosion in an uncontrolled public ground floor area, does the design prevent 
progressive collapse due to the loss of one primary column?
Do architectural or structural features provide a minimum 6-inch stand-off to the internal columns 
(primary vertical load carrying members)?
Are the columns in the unscreened internal spaces designed for an unbraced length equal to two floors, or 
three floors where there are two levels of parking?
Design to mitigate progressive collapse is an independent analysis to determine a systems ability to resist structural 
collapse upon the loss of a major structural element or the systems ability to resist the loss of a major structural 
element. Design to mitigate progressive collapse may be based on the methods outlined in ASCE 7-98 (now 7-02). 
Designers may apply static and/or dynamic methods of analysis to meet this requirement and ultimate load capacities 
may be assumed in the analyses. Combine structural upgrades for retrofits to existing buildings, such as seismic and 
progressive collapse, into a single project due to the economic synergies and other cross benefits. Existing facilities may 
be retrofitted to withstand the design level threat or to accept the loss of a column for one floor above grade at the 
building perimeter without progressive collapse. Note that collapse of floors or roof must not be permitted.
Reference: GSA PBS-P100


3.7
Are there adequate redundant load paths in the structure?

Special consideration should be given to materials that have inherent ductility and that are better able to respond to 
load reversals, such as cast in place reinforced concrete, reinforced masonry, and steel construction.
Careful detailing is required for material such as pre-stressed concrete, pre-cast concrete, and masonry to adequately 
respond to the design loads. Primary vertical load carrying members should be protected where parking is inside a 
facility and the building superstructure is supported by the parking structure.
Reference: GSA PBS-P100

3.8
Are there transfer girders supported by columns within unscreened public spaces or at the exterior of the 
building?

Transfer girders allow discontinuities in columns between the roof and foundation. This design has inherent 
difficulty in transferring load to redundant paths upon loss of a column or the girder. Transfer beams and girders 
that, if lost, may cause progressive collapse are highly discouraged.
Reference: GSA PBS-P100

3.9
What is the grouting and reinforcement of masonry (brick and/or concrete masonry unit (CMU)) exterior 
walls?

Avoid unreinforced masonry exterior walls. Reinforcement can run the range of light to heavy, depending upon the 
stand-off distance available and postulated design threat.
Reference: GSA PBS-P100 recommends fully grouted and reinforced CMU construction where CMU is selected.
Reference: DoD Minimum Antiterrorism Standards for Buildings states "Unreinforced masonry walls are prohibited 
for the exterior walls of new buildings. A minimum of 0.05 percent vertical reinforcement with a maximum spacing 
of 1200 mm (48 in) will be provided. For existing buildings, implement mitigating measures to provide an 
equivalent level of protection." [This is light reinforcement and based upon the recommended stand-off distance for 
the situation.] 

3.10
Will the loading dock design limit damage to adjacent areas and vent explosive force to the exterior of the 
building?
Design the floor of the loading dock for blast resistance if the area below is occupied or contains critical utilities.
Reference: GSA PBS-P100

3.11
Are mailrooms, where packages are received and opened for inspection, and unscreened retail spaces 
designed to mitigate the effects of a blast on primary vertical or lateral bracing members


Where mailrooms and unscreened retail spaces are located in occupied areas or adjacent to critical utilities, walls, 
ceilings, and floors, they should be blast- and fragment- resistant.
Methods to facilitate the venting of explosive forces and gases from the interior spaces to the outside of the structure 
may include blow-out panels and window system designs that provide protection from blast pressure applied to the 
outside, but that readily fail and vent if exposed to blast pressure on the inside.
Reference: GSA PBS-P10




4         Building Envelope


4.1

What is the designed or estimated protection level of the exterior walls against the postulated explosive 
threat?


The performance of the faade varies to a great extent on the materials. Different construction includes brick or 
stone with block backup, steel stud walls, precast panels, or curtain wall with glass, stone, or metal panel elements.
Shear walls that are essential to the lateral and vertical load bearing system and that also function as exterior walls 
should be considered primary structures and should resist the actual blast loads predicted from the threats specified. 
Where exterior walls are not designed for the full design loads, special consideration should be given to construction 
types that reduce the potential for injury.
Reference: GSA PBS-P100


4.2
Is there less than a 40 percent fenestration opening per structural bay?
Is the window system design on the exterior faade balanced to mitigate the hazardous effects of flying 
glazing following an explosive event? (glazing, frames, anchorage to supporting walls, etc.)
Do the glazing systems with a 12-inch (34-inch is better) bite contain an application of structural 
silicone?
Is the glazing laminated or is it protected with an anti-shatter (fragment retention) film?
If an anti-shatter film is used, is it a minimum of a 7-mil thick film, or specially manufactured 4-mil thick 
film?

The performance of the glass will similarly depend on the materials. Glazing may be single pane or double pane, 
monolithic or laminated, annealed, heat strengthened or fully tempered.
The percent fenestration is a balance between protection level, cost, the architectural look of the building within its 
surroundings, and building codes. One goal is to keep fenestration to below 40 percent of the building envelope 
vertical surface area, but the process must balance differing requirements. A blast engineer may prefer no windows; 
an architect may favor window curtain walls; building codes require so much fenestration per square footage of 
floor area; fire codes require a prescribed window opening area if the window is a designated escape route; and the 
building owner has cost concerns.
Ideally, an owner would want 100 percent of the glazed area to provide the design protection level against the 
postulated explosive threat (design basis threat weapon size at the expected stand-off distance). However, 
economics and geometry may allow 80 percent to 90 percent due to the statistical differences in the manufacturing 
process for glass or the angle of incidence of the blast wave upon upper story windows (4th floor and higher).
Reference: GSA PBS-P100



4.3
Do the walls, anchorage, and window framing fully develop the capacity of the glazing material selected?
Are the walls capable of withstanding the dynamic reactions from the windows?
Will the anchorage remain attached to the walls of the building during an explosive event without failure?
Is the faade connected to backup block or to the structural frame?
Are non-bearing masonry walls reinforced?

Government produced and sponsored computer programs coupled with test data and recognized dynamic 
structural analysis techniques may be used to determine whether the glazing either survives the specified threats or 
the post damage performance of the glazing protects the occupants. A breakage probability no higher than 750 
breaks per 1,000 may be used when calculating loads to frames and anchorage.
The intent is to ensure the building envelope provides relatively equal protection against the postulated explosive 
threat for the walls and window systems for the safety of the occupants, especially in rooms with exterior walls.
Reference: GSA PBS-P100 

4.4
Does the building contain ballistic glazing?
Does the ballistic glazing meet the requirements of UL 752 Bullet-Resistant Glazing?
Does the building contain security-glazing?
Does the security-glazing meet the requirements of ASTM F1233 or UL 972, Burglary Resistant Glazing 
Material?
Do the window assemblies containing forced entry resistant glazing (excluding the glazing) meet the 
requirements of ASTM F 588?

Glass-clad polycarbonate or laminated polycarbonate are two types of acceptable glazing material.
If windows are upgraded to bullet-resistant, burglar-resistant, or forced entry-resistant, ensure that doors, ceilings, 
and floors, as applicable, can resist the same for the areas of concern.
Reference: GSA PBS-P100

4.5
Do non-window openings, such as mechanical vents and exposed plenums, provide the same level of 
protection required for the exterior wall


In-filling of blast over-pressures must be considered through non-window openings such that structural members 
and all mechanical system mountings and attachments should resist these interior fill pressures.
These non-window openings should also be as secure as the rest of the building envelope against forced entry.
Reference: GSA PBS-P10




5         Utility Systems

5.


What is the source of domestic water? (utility, municipal, wells, lake, river, storage tank)
Is there a secure alternate drinking water supply?


Domestic water is critical for continued building operation. Although bottled water can satisfy requirements for 
drinking water and minimal sanitation, domestic water meets many other needs  flushing toilets, building heating 
and cooling system operation, cooling of emergency generators, humidification, etc.
Reference: FEMA 386-7

5.2
Are there multiple entry points for the water supply?

If the building or site has only one source of water entering at one location, the entry point should be secure.
Reference: GSA PBS-P100

5.3
Is the incoming water supply in a secure location?

Ensure that only authorized personnel have access to the water supply and its components.
Reference: FEMA 386-7

5.4
Does the building or site have storage capacity for domestic water?
How many gallons of storage capacity are available and how long will it allow operations to continue?


Operational facilities will require reliance on adequate domestic water supply. Storage capacity can meet short-term 
needs and use water trucks to replenish for extended outages.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities.

5.5
What is the source of water for the fire suppression system? (local utility company lines, storage tanks 
with utility company backup, lake, or river)
Are there alternate water supplies for fire suppression?

The fire suppression system water may be supplied from the domestic water or it may have a separate source, 
separate storage, or nonpotable alternate sources.
For a site with multiple buildings, the concern is that the supply should be adequate to fight the worst case situation 
according to the fire codes. Recent major construction may change that requirement.
Reference: FEMA 386-7

5.6
Is the fire suppression system adequate, code-compliant, and protected (secure location)?

Standpipes, water supply control valves, and other system components should be secure or supervised.
Reference: FEMA 386-7

5.7
Do the sprinkler/standpipe interior controls (risers) have fire- and blast-resistant separation?
Are the sprinkler and standpipe connections adequate and redundant?
Are there fire hydrant and water supply connections near the sprinkler/standpipe connections?
The incoming fire protection water line should be encased, buried, or located 50 feet from high-risk areas. The 
interior mains should be looped and sectionalized.
Reference: GSA PBS-P100

5.8
Are there redundant fire water pumps (e.g., one electric, one diesel)?
Are the pumps located apart from each other?



Collocating fire water pumps puts them at risk for a single incident to disable the fire suppression system.
References: GSA PBS-P100 and FEMA 386-7

5.9
Are sewer systems accessible?
Are they protected or secured?

Sanitary and stormwater sewers should be protected from unauthorized access. The main concerns are backup or 
flooding into the building, causing a health risk, shorting out electrical equipment, and loss of building use.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

5.10
What fuel supplies do the building rely upon for critical operation?
Typically, natural gas, propane, or fuel oil are required for continued operation.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

5.11
How much fuel is stored on the site or at the building and how long can this quantity support critical 
operations?
How is it stored?
How is it secured?

Fuel storage protection is essential for continued operation.
Main fuel storage should be located away from loading docks, entrances, and parking. Access should be restricted 
and protected (e.g., locks on caps and seals).
References: GSA PBS-P100 and Physical Security Assessment for the Department of Veterans Affairs Facilities

5.12
Where is the fuel supply obtained?
How is it delivered?

The supply of fuel is dependent on the reliability of the supplier.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

5.12
Are there alternate sources of fuel?
Can alternate fuels be used?

Critical functions may be served by alternate methods if normal fuel supply is interrupted.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

5.14
What is the normal source of electrical service for the site or building?

Utilities are the general source unless co-generation or a private energy provider is available.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

5.15
Is there a redundant electrical service source?
Can the site or buildings be fed from more than one utility substation?
The utility may have only one source of power from a single substation. There may be only single feeders from the 
main substation.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

5.16
How many service entry points does the site or building have for electricity?


Electrical supply at one location creates a vulnerable situation unless an alternate source is available.
Ensure disconnecting requirements according to NFPA 70 (National Fire Protection Association, National Electric 
Code) are met for multiple service entrances.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

5.17
Is the incoming electric service to the building secure?

 Typically, the service entrance is a locked room, inaccessible to the public.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

5.18
What provisions for emergency power exist? What systems receive emergency power and have capacity 
requirements been tested? 

Is the emergency power collocated with the commercial electric service?
Is there an exterior connection for emergency power?

Besides installed generators to supply emergency power, portable generators or rental generators available under 
emergency contract can be quickly connected to a building with an exterior quick disconnect already installed.
Testing under actual loading and operational conditions ensures the critical systems requiring emergency power 
receive it with a high assurance of reliability.
Reference: GSA PBS-P100

5.19
By what means do the main telephone and data communications interface the site or building?
Typically, communication ducts or other conduits are available. Overhead service is more identifiable and vulnerable.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
5.20
Are there multiple or redundant locations for the telephone and communications service? 

Secure locations of communications wiring entry to the site or building are required.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
5.21
Does the fire alarm system require communication with external sources?
By what method is the alarm signal sent to the responding agency: telephone, radio, etc.?
Is there an intermediary alarm monitoring center?
Typically, the local fire department responds to an alarm that sounds at the station or is transmitted over phone lines 
by an auto dialer.
An intermediary control center for fire, security, and/or building system alarms may receive the initial notification at 
an on-site or off-site location. This center may then determine the necessary response and inform the responding 
agency.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

5.22
Are utility lifelines aboveground, underground, or direct buried?

Utility lifelines (water, power, communications, etc.) can be protected by concealing, burying, or encasing.
References: GSA PBS-P100 and FEMA 386-



6        Mechanical Systems (HVAC and CBR)


6.


6.1
Where are the air intakes and exhaust louvers for the building? (low, high, or midpoint of the building 
structure)
Are the intakes and exhausts accessible to the public?



Air intakes should be located on the roof or as high as possible. Otherwise secure within CPTED-compliant fencing or 
enclosure. The fencing or enclosure should have a sloped roof to prevent the throwing of anything into the 
enclosure near the intakes.
Reference: GSA PBS-P100 states that air intakes should be on the fourth floor or higher and, on buildings with three 
floors or less, they should be on the roof or as high as practical. Locating intakes high on a wall is preferred over a 
roof location.
Reference: DoD UFC 4-010-01 states that, for all new inhabited buildings covered by this document, all air intakes 
should be located at least 3 meters (10 feet) above the ground.
Reference: CDC/NIOSH, Pub 2002-139 states: "An extension height of 12 feet (3.7 m) will place the intake out of 
reach of individuals without some assistance. Also, the entrance to the intake should be covered with a sloped metal 
mesh to reduce the threat of objects being tossed into the intake. A minimum slope of 45 is generally adequate. 
Extension height should be increased where existing platforms or building features (i.e., loading docks, retaining 
walls) might provide access to the outdoor air intakes".
Reference: LBNL PUB-51959: Exhausts are also a concer n during an outdoor release, especially if exhaust fans are 
not in continuous operation, due to wind effects and chimney effects (air movement due to differential 
temperature). 

6.2
Is roof access limited to authorized personnel by means of locking mechanisms?
Is access to mechanical areas similarly controlled?

Roofs are like entrances to the building and are like mechanical rooms when HVAC is installed. Adjacent structures or 
landscaping should not allow access to the roof.
References: GSA PBS-P100, CDC/NIOSH Pub 2002-139, and LBNL Pub 51959

6.3
Are there multiple air intake locations?

Single air intakes may feed several air handling units. Indicate if the air intakes are localized or separated. Installing 
low-leakage dampers is one way to provide the system separation when necessary.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities


6.4
What are the types of air filtration? Include the efficiency and number of filter modules for each of the 
main air handling systems?
Is there any collective protection for chemical, biological, and radiological contamination designed into 
the building?

MERV  Minimum Efficiency Reporting Value
HEPA  High Efficiency Particulate Air
Activated charcoal for gases
Ultraviolet C for biologicals
Consider mix of approaches for optimum protection and cost-effectiveness.
Reference: CDC/NIOSH Pub 2002-139

6.5
Is there space for larger filter assemblies on critical air handling systems?

Air handling units serving critical functions during continued operation may be retrofitted to provide enhanced 
protection during emergencies. However, upgraded filtration may have negative effects upon the overall air handling 
system operation, such as increased pressure drop.
Reference: CDC/NIOSH Pub 2002-139

6.6
Are there provisions for air monitors or sensors for chemical or biological agents?


Duct mounted sensors are usuallly found in limited cases in laboratory areas. Sensors generally have a limited 
spectrum of high reliability and are costly. Many different technologies are undergoing research to provide capability. 
Reference: CDC/NIOSH Pub 2002-139

6.7
By what method are air intakes and exhausts closed when not operational?

Motorized (low-leakage, fast-acting) dampers are the preferred method for closure with fail-safe to the closed 
position so as to support in-place sheltering.
References: CDC/NIOSH Pub 2002-139 and LBNL Pub 51959

6.8
How are air handling systems zoned?
What areas and functions do each of the primary air handling systems serve?
Understanding the critical areas of the building that must continue functioning focuses security and hazard 
mitigation measures.
Applying HVAC zones that isolate lobbies, mailrooms, loading docks, and other entry and storage areas from the rest 
of the building HVAC zones and maintaining negative pressure within these areas will contain CBR releases. Identify 
common return systems that service more than one zone, effectively making a large single zone.
Conversely, emergency egress routes should receive positive pressurization to ensure contamination does not hinder 
egress. Consider filtering of the pressurization air.
References: CDC/NIOSH Pub 2002-139 and LBNL Pub 51959


6.9
Are there large central air handling units or are there multiple units serving separate zones?

Independent units can continue to operate if damage occurs to limited areas of the building.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

6.10
Are there any redundancies in the air handling system?
Can critical areas be served from other units if a major system is disabled?


Redundancy reduces the security measures required compared to a non-redundant situation.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

6.11
Is the air supply to critical areas compartmentalized?
Similarly, are the critical areas or the building as a whole, considered tight with little or no leakage?
During chemical, biological, and radiological situations, the intent is to either keep the contamination localized in 
the critical area or prevent its entry into other critical, non-critical, or public areas. Systems can be cross-connected 
through building openings (doorways, ceilings, partial wall), ductwork leakage, or pressure differences in air 
handling system. In standard practice, there is almost always some air carried between ventilation zones by pressure 
imbalances, due to elevator piston action, chimney effect, and wind effects.
Smoke testing of the air supply to critical areas may be necessary.
Reference: CDC/NIOSH Pub 2002-139 and LBNL Pub 51959




6.12
Are supply, return, and exhaust air systems for critical areas secure?
Are all supply and return ducts completely connected to their grilles and registers and secure?
Is the return air not ducted?

The air systems to critical areas should be inaccessible to the public, especially if the ductwork runs through the 
public areas of the building. It is also more secure to have a ducted air handling system versus sharing hallways and 
plenums above drop ceilings for return air. Non-ducted systems provide greater opportunity for introducing 
contaminants.
Reference: CDC/NIOSH Pub 2002-139 and LBNL Pub 51959

6.13
What is the method of temperature and humidity control?
Is it localized or centralized?
Central systems can range from monitoring only to full control. Local control may be available to override central 
operation.
Of greatest concern are systems needed before, during, and after an incident that may be unavailable due to 
temperature and humidity exceeding operational limits (e.g., main telephone switch room).
Reference: DOC CIAO Vulnerability Assessment Framework 1.1
6.14
Where are the building automation control centers and cabinets located?
Are they in secure areas?
How is the control wiring routed?


Access to any component of the building automation and control system could compromise the functioning of the 
system, increasing vulnerability to a hazard or precluding their proper operation during a hazard incident.
The HVAC and exhaust system controls should be in a secure area that allows rapid shutdown or other activation 
based upon location and type of attack.
References: FEMA 386-7, DOC CIAO Vulnerability Assessment Framework 1.1 and LBNL Pub 51959

6.15
Does the control of air handling systems support plans for sheltering in place or other protective 
approach?

The micro-meteorological effects of buildings and terrain can alter travel and duration of chemical agents and 
hazardous material releases. Shielding in the form of sheltering in place can protect people and property from 
harmful effects.
To support in-place sheltering, the air handling systems require the ability for authorized personnel to rapidly turn 
off all systems. However, if the system is properly filtered, then keeping the system operating will provide protection 
as long as the air handling system does not distribute an internal release to other portions of the building.
Reference: CDC/NIOSH Pub 2002-139
6.16
Are there any smoke evacuation systems installed?
Does it have purge capability?

For an internal blast, a smoke removal system may be essential, particularly in large, open spaces. The equipment 
should be located away from high-risk areas, the system controls and wiring should be protected, and it should be 
connected to emergency power. This exhaust capability can be built into areas with significant risk on internal 
events, such as lobbies, loading docks, and mailrooms. Consider filtering of the exhaust to capture CBR 
contaminants.
References: GSA PBS-P100, CDC/NIOSH Pub 2002-139, and LBNL Pub 51959
6.17
Where is roof-mounted equipment located on the roof? (near perimeter, at center of roof)

Roof-mounted equipment should be kept away from the building perimeter.
Reference: U.S. Army TM 5-853
6.18
Are fire dampers installed at all fire barriers?
Are all dampers functional and seal well when closed?

All dampers (fire, smoke, outdoor air, return air, bypass) must be functional for proper protection within the 
building during an incident.
Reference: CDC/NIOSH Pub 2002-139
6.19
Do fire walls and fire doors maintain their integrity?
The tightness of the building (both exterior, by weatherization to seal cracks around doors and windows, and 
internal, by zone ducting, fire walls, fire stops, and fire doors) provides energy conservation benefits and functional 
benefits during a CBR incident.
Reference: LBNL Pub 51959
6.20
Do elevators have recall capability and elevator emergency message capability?

Although a life-safety code and fire response requirement, the control of elevators also has benefit during a CBR 
incident. The elevators generate a piston effect, causing pressure differentials in the elevator shaft and associated 
floors that can force contamination to flow up or down. 
Reference: LBNL Pub 51959
6.21
Is access to building information restricted?

Information on building operations, schematics, procedures, plans, and specifications should be strictly controlled 
and available only to authorized personnel.
References: CDC/NIOSH Pub 2002-139 and LBNL Pub 51959
6.22
Does the HVAC maintenance staff have the proper training, procedures, and preventive maintenance 
schedule to ensure CBR equipment is functional?

Functional equipment must interface with operational procedures in an emergency plan to ensure the equipment is 
properly operated to provide the protection desired.
The HVAC system can be operated in different ways, depending upon an external or internal release and where in 
the building an internal release occurs. Thus maintenance and security staff must have the training to properly 
operate the HVAC system under different circumstances, even if the procedure is to turn off all air movement 
equipment. 
Reference: CDC/NIOSH Pub 2002-139 and LBNL Pub 5195



7        Plumbing and Gas System


7.


What is the method of water distribution?


Central shaft locations for piping are more vulnerable than multiple riser locations.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

7.2
What is the method of gas distribution? (heating, cooking, medical, process


Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

7.3
Is there redundancy to the main piping distribution?
Looping of piping and use of section valves provide redundancies in the event sections of the system are damaged.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

7.4
What is the method of heating domestic water?
What fuel(s) is used?

Single source of hot water with one fuel source is more vulnerable than multiple sources and multiple fuel types. 
Domestic hot water availability is an operational concern for many building occupancies.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

7.5
Where are gas storage tanks located? (heating, cooking, medical, process)
How are they piped to the distribution system? (above or below ground)


The concern is that the tanks and piping could be vulnerable to a moving vehicle or a bomb blast either directly or 
by collateral damage due to proximity to a higher-risk area.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

7.6
Are there reserve supplies of critical gases?

Localized gas cylinders could be available in the event of damage to the central tank system.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilitie




8        Electrical Systems
8.1
Are there any transformers or switchgears located outside the building or accessible from the building 
exterior?
Are they vulnerable to public access?
Are they secured?

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities


8.2
What is the extent of the external building lighting in utility and service areas and at normal entryways 
used by the building occupants?



Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

8.3
How are the electrical rooms secured and where are they located relative to other higher-risk areas, starting 
with the main electrical distribution room at the service entrance?
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

8.4
Are critical electrical systems collocated with other building systems?
Are critical electrical systems located in areas outside of secured electrical areas?
Is security system wiring located separately from electrical and other service systems?

Collocation concerns include rooms, ceilings, raceways, conduits, panels, and risers.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities


8.5
How are electrical distribution panels serving branch circuits secured or are they in secure locations?

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

8.6
Does emergency backup power exist for all areas within the building or for critical areas only?
How is the emergency power distributed?
Is the emergency power system independent from the normal electrical service, particularly in critical 
areas?


There should be no single critical node that allows both the normal electrical service and the emergency backup 
power to be affected by a single incident. Automatic transfer switches and interconnecting switchgear are the initial 
concerns.
Emergency and normal electrical equipment should be installed separately, at different locations, and as far apart as 
possible.
Reference: GSA PBS-P100

8.7
How is the primary electrical system wiring distributed?
Is it collocated with other major utilities?
Is there redundancy of distribution to critical areas?

Central utility shafts may be subject to damage, especially if there is only one for the building.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilitie






9         Fire Alarm System


9.1
Is the building fire alarm system centralized or localized?

How are alarms made known, both locally and centrally?

Are critical documents and control systems located in a secure yet accessible location


Fire alarm systems must first warn building occupants to evacuate for life safety. Then they must inform the 
responding agency to dispatch fire equipment and personnel.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

9.2
Where are the fire alarm panels located?
Do they allow access to unauthorized personnel?

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

9.3
Is the fire alarm system standalone or integrated with other functions such as security and environmental 
or building management systems?
What is the interface?

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

9.4
Do key fire alarm system components have fire- and blast-resistant separation?




This is especially necessary for the fire command center or fire alarm control center. The concern is to similarly 
protect critical components as described in Items 2.19, 5.7, and 10.3.

9.5
Is there redundant off-premises fire alarm reporting?

Fire alarms can ring at a fire station, at an intermediary alarm monitoring center, or autodial someone else. See Items 
5.21 and 10.5




10        Communications and IT Systems


10.1
Where is the main telephone distribution room and where is it in relation to higher-risk areas?
Is the main telephone distribution room secure?

One can expect to find voice, data, signal, and alarm systems to be routed through the main telephone distribution 
room.
Reference: FEMA 386-7

10.2
Does the telephone system have an uninterruptible power supply (UPS)?
What is its type, power rating, and operational duration under load, and location? (battery, on-line, 
filtered)


Many telephone systems are now computerized and need a UPS to ensure reliability during power fluctuations. The 
UPS is also needed to await any emergency power coming on line or allow orderly shutdown.
Reference: DOC CIAO Vulnerability Assessment Framework 1.1

10.3
Where are communication systems wiring closets located? (voice, data, signal, alarm)
Are they collocated with other utilities?
Are they in secure areas?
Concern is to have separation distance from other utilities and higher-risk areas to avoid collateral damage.
Security approaches on the closets include door alarms, closed circuit television, swipe cards, or other logging 
notifications to ensure only authorized personnel have access to these closets.
Reference: FEMA 386-7

10.4
How is the communications system wiring distributed? (secure chases and risers, accessible public areas)


The intent is to prevent tampering with the systems.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

10.5
Are there redundant communications systems available?


Critical areas should be supplied with multiple or redundant means of communications. Power outage phones can 
provide redundancy as they connect directly to the local commercial telephone switch off site and not through the 
building telephone switch in the main telephone distribution room.
A base radio communication system with antenna can be installed in stairwells, and portable sets distributed to 
floors.
References: GSA PBS-P100 and FEMA 386-7



10.6
Where are the main distribution facility, data centers, routers, firewalls, and servers located and are they 
secure?
Where are the secondary and/or intermediate distribution facilities and are they secure?

Concern is collateral damage from manmade hazards and redundancy of critical functions.
Reference: DOC CIAO Vulnerability Assessment Framework 1.1

10.7
What type and where are the Wide Area Network (WAN) connections?
Critical facilities should have two Minimum-Points-of-Presence( MPOPs) where the telephone companys outside 
cable terminates inside the building. It is functionally a service entrance connection that demarcates where the 
telephone companys property stops and the building owners property begins. The MPOPs should not be 
collocated and they should connect to different telephone company central offices so that the loss of one cable or 
central office does not reduce capability.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

10.8
What are the type, power rating, and location of the uninterruptible power supply? (battery, on-line, 
filtered)
Are the UPS also connected to emergency power?


Consider that UPS should be found at all computerized points from the main distribution facility to individual data 
closets and at critical personal computers/terminals.
Critical LAN sections should also be on backup power.
Reference: DOC CIAO Vulnerability Assessment Framework 1.1

10.9
What type of Local Area Network (LAN) cabling and physical topology is used? (Category (Cat) 5, Gigabit 
Ethernet, Ethernet, Token Ring) 

The physical topology of a network is the way in which the cables and computers are connected to each other. The 
main types of physical topologies are:
Bus (single radial where any damage on the bus affects the whole system, but especially all portions downstream)
Star (several computes are connected to a hub and many hubs can be in the network  the hubs can be critical 
nodes, but the other hubs continue to function if one fails)
Ring (a bus with a continuous connection - least used, but can tolerate some damage because if the ring fails at a 
single point it can be rerouted much like a looped electric or water system)
The configuration and the availability of surplus cable or spare capacity on individual cables can reduce vulnerability 
to hazard incidents.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
10.10
For installed radio/wireless systems, what are their types and where are they located?(radio frequency 
(RF), high frequency (HF), very high frequency (VHF), medium wave (MW))

Depending upon the function of the wireless system, it could be susceptible to accidental or intended jamming or 
collateral damage.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities


10.11
Do the Information Technology (IT - computer) systems meet requirements of confidentiality, integrity, 
and availability?
Ensure access to terminals and equipment for authorized personnel only and ensure system up-time to meet 
operational needs.
Reference: DOC CIAO Vulnerability Assessment Framework 1.1

10.12
Where is the disaster recovery/mirroring site?


A site with suitable equipment that allows continuation of operations or that mirrors (operates in parallel to) the 
existing operation is beneficial if equipment is lost during a natural or manmade disaster. The need is based upon the 
criticality of the operation and how quickly replacement equipment can be put in place and operated.
Reference: DOC CIAO Vulnerability Assessment Framework 1.1
10.13
Where is the backup tape/file storage site and what is the type of safe environment?(safe, vault, 
underground)
Is there redundant refrigeration in the site?
If equipment is lost, data are most likely lost, too. Backups are needed to continue operations at the disaster 
recovery site or when equipment can be delivered and installed.
Reference: DOC CIAO Vulnerability Assessment Framework 1.1
10.14
Are there any satellite communications (SATCOM) links?(location, power, UPS, emergency power, spare 
capacity/capability)


SATCOM links can serve as redundant communications for voice and data if configured to support required 
capability after a hazard incident. 
Reference: DOC CIAO Vulnerability Assessment Framework 1.1
10.15
Is there a mass notification system that reaches all building occupants? (public address, pager, cell phone, 
computer override, etc.)
Will one or more of these systems be operational under hazard conditions? (UPS, emergency power) 

Depending upon building size, a mass notification system will provide warning and alert information, along with 
actions to take before and after an incident if there is redundancy and power.
Reference: DoD UFC 4-010-01

10.16
Do control centers and their designated alternate locations have equivalent or reduced capability for voice, 
data, mass notification, etc.?(emergency operations, security, fire alarms, building automation)
Do the alternate locations also have access to backup systems, including emergency power?


Reference: GSA PBS-P10





11        Equipment Operations and Maintenanc


11.


Are there composite drawings indicating location and capacities of major systems and are they current? 
(electrical, mechanical, and fire protection; and date of last update)
Do updated operations and maintenance (O&M) manuals exist?
Within critical infrastructure protection at the building level, the current configuration and capacity of all critical 
systems must be understood to ensure they meet emergency needs. Manuals must also be current to ensure 
operations and maintenance keeps these systems properly functioning. The system must function during an 
emergency unless directly affected by the hazard incident.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

11.2
Have critical air systems been rebalanced?
If so, when and how often?
Although the system may function, it must be tested periodically to ensure it is performing as designed. Balancing is 
also critical after initial construction to set equipment to proper performance per the design.
Rebalancing may only occur during renovation.
Reference: CDC/NIOSH Pub 2002-139

11.3
Is air pressurization monitored regularly?
Some areas require positive or negative pressure to function properly. Pressurization is critical in a hazardous 
environment or emergency situation.
Measuring pressure drop across filters is an indication when filters should be changed, but also may indicate that low 
pressures are developing downstream and could result in loss of expected protection.
Reference: CDC/NIOSH Pub 2002-139


11.4
Does the building have a policy or procedure for periodic recommissioning of major 
Mechanical/Electrical/Plumbing (M/E/P) systems?



Recommissioning involves testing and balancing of systems to ascertain their capability to perform as described.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

11.5
Is there an adequate O&M program, including training of facilities management staff?

If O&M of critical systems is done with in-house personnel, management must know what needs to be done and the 
workforce must have the necessary training to ensure systems reliability.
Reference: CDC/NIOSH Pub 2002-139

11.6
What maintenance and service agreements exist for M/E/P systems?
When an in-house facility maintenance work force does not exist or does not have the capability to perform the 
work, maintenance and service contracts are the alternative to ensure critical systems will work under all conditions. 
The facility management staff requires the same knowledge to oversee these contracts as if the work was being done 
by in-house personnel.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

11.7
Are backup power systems periodically tested under load?


Loading should be at or above maximum connected load to ensure available capacity and automatic sensors should 
be tested at least once per year.
Periodically (once a year as a minimum) check the duration of capacity of backup systems by running them for the 
expected emergency duration or estimating operational duration through fuel consumption, water consumption, 
or voltage loss.
Reference: FEMA 386-7


11.8
Is stairway and exit sign lighting operational?


The maintenance program for stairway and exit sign lighting (all egress lighting) should ensure functioning under 
normal and emergency power conditions.
Expect building codes to be updated as emergency egress lighting is moved from upper walls and over doorways to 
floor level as heat and smoke drive occupants to crawl along the floor to get out of the building. Signs and lights 
mounted high have limited or no benefit when obscured.
Reference: FEMA 386-




12        Security System


            Perimeter System

12.


Are black/white or color CCTV (closed circuit television) cameras used?
Are they monitored and recorded 24 hours/7 days a week? By whom?
Are they analog or digital by design?    
What are the number of fixed, wireless, and pan-tilt-zoom cameras used?        
Who are the manufacturers of the CCTV cameras?
What is the age of the CCTV cameras in use? 
Security technology is frequently considered to complement or supplement security personnel forces and to provide 
a wider area of coverage. Typically, these physical security elements provide the first line of defense in deterring, 
detecting, and responding to threats and reducing vulnerabilities. They must be viewed as an integral component of 
the overall security program. Their design, engineering, installation, operation, and management must be able to 
meet daily security challenges from a cost-effective and efficiency perspective. During and after an incident, the 
system, or its backups, should be functional per the planned design.
Consider color CCTV cameras to view and record activity at the perimeter of the building, particularly at primary 
entrances and exits. A mix of monochrome cameras should be considered for areas that lack adequate illumination 
for color cameras.
Reference: GSA PBS P-100

12.2
Are the cameras programmed to respond automatically to perimeter building alarm events?
Do they have built-in video motion capabilities?

 

The efficiency of monitoring multiple screens decreases as the number of screens increases. Tying the alarm system or 
motion sensors to a CCTV camera and a monitoring screen improves the man-machine interface by drawing 
attention to a specific screen and its associated camera. Adjustment may be required after installation due to initial 
false alarms, usually caused by wind or small animals.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

12.3
What type of camera housings are used and are they environmental in design to protect against exposure to 
heat and cold weather elements? 
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

12.4
Are panic/duress alarm buttons or sensors used, where are they located, and are they hardwired or 
portable?
 


Call buttons should be provided at key public contact areas and as needed in offices of managers and directors, in 
garages and parking lots, and other high-risk locations by assessment.
Reference: GSA PBS P-100

12.5
Are intercom call boxes used in parking areas or along the building perimeter?

See Item 12.4.
12.6
What is the transmission media used to transmit camera video signals: fiber, wire line, telephone wire, 
coaxial, wireless? 
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
12.7
Who monitors the CCTV system? 

Reference: DOC CIAO Vulnerability Assessment Framework 1.1
12.8
What is the quality of video images both during the day and hours of darkness?
Are infrared camera illuminators used?

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
 
12.9
Are the perimeter cameras supported by an uninterruptible power supply, battery, or building emergency 
power?


Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

12.10
What type of exterior Intrusion Detection System (IDS) sensors are used? (electromagnetic; fiber optic; 
active infrared; bistatic microwave; seismic; photoelectric; ground; fence; glass break (vibration/shock); 
single, double, and roll-up door magnetic contacts or switches) 
Consider balanced magnetic contact switch sets for all exterior doors, including overhead/roll-up doors, and review 
roof intrusion detection.
Consider glass break sensors for windows up to scalable heights.
Reference: GSA PBS-P100
12.11
Is a global positioning system (GPS) used to monitor vehicles and asset movements? 

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

Interior Security

12.12
Are black/white or color CCTV cameras used?
Are they monitored and recorded 24 hours/7 days a week? By whom?
Are they analog or digital by design?
What are the number of fixed, wireless, and pan-tilt-zoom cameras used?
Who are the manufacturers of the CCTV cameras?
What is the age of the CCTV cameras in use? 

See Item 12.1.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

12.13
Are the cameras programmed to respond automatically to interior building alarm events?
Do they have built-in video motion capabilities?
 
The efficiency of monitoring multiple screens decreases as the number of screens increases. Tying the alarm system or 
motion sensors to a CCTV camera and a monitoring screen improves the man-machine interface by drawing 
attention to a specific screen and its associated camera.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

12.14
What type of camera housings are used and are they designed to protect against exposure or tampering? 


Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

12.15
Do the camera lenses used have the proper specifications, especially distance viewing and clarity? 

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

12.16
What is the transmission media used to transmit camera video signals: fiber, wire line, telephone wire, 
coaxial, wireless? 

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

12.17
Are the interior camera video images of good visual and recording quality? 

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
12.18
Are the interior cameras supported by an uninterruptible power supply source, battery, or building 
emergency power? 

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
12.19
What are the first costs and maintenance costs associated with the interior cameras? 


Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
12.20
What type of security access control system is used?
Are the devices used for physical security also used (integrated) with security computer networks (e.g., in 
place of or in combination with user ID and system passwords)? 

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
12.21
What type of access control transmission media is used to transmit access control system signals (same as 
defined for CCTV cameras)? 

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

12.22
What is the backup power supply source for the access control systems? (battery, uninterruptible power 
supply) 

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
12.23
What access control system equipment is used?

How old are the systems and what are the related first and maintenance service costs? 
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

12.24
Are panic/duress alarm sensors used?
Where are they located?
Are they hardwired or portable? 

Call buttons should be provided at key public contact areas and as needed in offices of managers and directors, in 
garages and parking lots, and other high-risk locations by assessment.
Reference: GSA PBS P-100
12.25
Are intercom call-boxes or a building intercom system used throughout the building? 

See Item 12.24.
12.26
Are magnetometers (metal detectors) and x-ray equipment used? 
At what locations within the building? 

Reference: DOC CIAO Vulnerability Assessment Framework 1.1

12.27
What type of interior IDS sensors are used: electromagnetic; fiber optic; active infrared-motion detector; 
photoelectric; glass break (vibration/shock); single, double, and roll-up door magnetic contacts or 
switches? 


Consider magnetic reed switches for interior doors and openings.
Reference: GSA PBS-P100
12.28
Are mechanical, electrical, gas, power supply, radiological material storage, voice/data telecommunication 
system nodes, security system panels, elevator and critical system panels, and other sensitive rooms 
continuously locked, under electronic security, CCTV camera, and intrusion alarm systems surveillance? 

Reference: DOC CIAO Vulnerability Assessment Framework 1.1
12.29
What types of locking hardware are used throughout the building?
Are manual and electromagnetic cipher, keypad, pushbutton, panic bar, door strikes, and related hardware 
and software used?

As a minimum, electric utility closets, mechanical rooms, and telephone closets should be secured.
The mailroom should also be secured, allowing only authorized personnel into the area where mail is screened and 
sorted. Separate the public access area from the screening area for the postulated mailroom threats.
All security locking arrangements on doors used for egress must comply with NFPA 101, Life Safety Code.
Reference: GSA PBS-P100

12.30
Are any potentially hazardous chemicals, combustible, or toxic materials stored on site in non-secure and 
non-monitored areas? 

The storage, use, and handling locations should also be kept away from other activities. 
The concern is that an intruder need not bring the material into the building if it is already there and accessible.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
12.31
What security controls are in place to handle the processing of mail and protect against potential 
biological, explosive, or other threatening exposures? 

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
12.32
Is there a designated security control room and console in place to monitor security, fire alarm, and other 
building systems?
Is there a backup control center designated and equipped?
Is there off-site 24-hour monitoring of intrusion detection systems?
Monitoring can be done at an off-site facility, at an on-site monitoring center during normal duty hours, or at a 24-
hour on-site monitoring center.
Reference: GSA PBS-P100
12.33
Is the security console and control room adequate in size and does it provide room for expansion?
Does it have adequate environment controls (e.g., a/c, lighting, heating, air circulation, backup power)?
Is it ergonomically designed?

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

12.34
Is the location of the security room in a secure area with limited, controlled, and restricted access controls 
in place?

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
12.35
What are the means by which facility and security personnel can communicate with one another (e.g., 
portable radio, pager, cell phone, personal data assistants (PDAs))?
What problems have been experienced with these and other electronic security systems?


Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
12.36
Is there a computerized security incident reporting system used to prepare reports and track security 
incident trends and patterns? 

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

12.37
Does the current security force have access to a computerized guard tour system? 

This system allows for the systematic performance of guard patrols with validation indicators built in. The system 
notes stations/locations checked or missed, dates and times of such patrols, and who conducted them on what 
shifts. Management reports can be produced for recordkeeping and manpower analysis purposes.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
12.38
Are vaults or safes in the building?
Where are they located?
Basic structural design requires an understanding of where heavy concentrations of floor loading may occur so as to 
strengthen the floor and structural framing to handle this downward load. Security design also needs this 
information to analyze how this concentrated load affects upward and downward loadings under blast conditions 
and its impact upon progressive collapse. Location is important because safes can be moved by blast so that they 
should be located away from people and away from exterior windows.
Vaults, on the other hand, require construction above the building requirements with thick masonry walls and steel 
reinforcement. A vault can provide protection in many instances due to its robust construction.
Safes and vaults may also require security sensors and equipment, depending upon the level of protection and 
defensive layers needed.
Reference: U.S. Army TM 5-85
Security System Documents
12.39
Have security system as-built drawings been generated and are they ready for review? 

Drawings are critical to the consideration and operation of security technologies, including its overall design and 
engineering processes. These historical reference documents outline system specifications and layout security devices 
used, as well as their application, location, and connectivity. They are a critical resource tool for troubleshooting 
system problems, and replacing and adding other security system hardware and software products. Such documents 
are an integral component to new and retrofit construction projects.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities





12.40
Have security system design and drawing standards been developed? 


Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
12.41
Are security equipment selection criteria defined? 
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

12.42
What contingency plans have been developed or are in place to deal with security control center 
redundancy and backup operations?

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
12.43
Have security system construction specification documents been prepared and standardized?

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
12.44
Do all security system documents include current as-built drawings? 

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
12.45
Have qualifications been determined for security consultants, system designers/engineers, installation 
vendors, and contractors? 

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

12.46
Are security systems decentralized, centralized, or integrated?
Do they operate over an existing IT network or are they a standalone method of operation? 

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
12.47
What security systems manuals are available?

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
12.48
What maintenance or service agreements exist for security systems?

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilitie


13         Security Master Pla


13.

Does a written security plan exist for this site or building?
When was the initial security plan written and last revised?
Who is responsible for preparing and reviewing the security plan?
The development and implementation of a security master plan provides a roadmap that outlines the strategic 
direction and vision, operational, managerial, and technological mission, goals, and objectives of the organizations 
security program.
Reference: DOC CIAO Vulnerability Assessment Framework 1.1
13.2
Has the security plan been communicated and disseminated to key management personnel and 
departments?



The security plan should be part of the building design so that the construction or renovation of the structure 
integrates with the security procedures to be used during daily operations.
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

13.3
Has the security plan been benchmarked or compared against related organizations and operational 
entities?

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
13.4
Has the security plan ever been tested and evaluated from a benefit/cost and operational efficiency and 
effectiveness perspective?

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

13.5
Does the security plan define mission, vision, and short- and long- term security program goals and 
objectives?

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
13.6
Are threats/hazards, vulnerabilities, and risks adequately defined and security countermeasures addressed 
and prioritized relevant to their criticality and probability of occurrence?


Reference: DOC CIAO Vulnerability Assessment Framework 1.1
13.7
Has a security implementation schedule been established to address recommended security solutions?




Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
13.8
Have security operating and capital budgets been addressed, approved, and established to support the plan?

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
13.9
What regulatory or industry guidelines/standards were followed in the preparation of the security plan?
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

13.10
Does the security plan address existing security conditions from an administrative, operational, 
managerial, and technical security systems perspective?


Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

13.11
Does the security plan address the protection of people, property, assets, and information?
Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities
13.12
Does the security plan address the following major components: access control, surveillance, response, 
building hardening, and protection against CBR and cyber-network attacks?

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

13.13
Has the level of risk been identified and communicated in the security plan through the performance of a 
physical security assessment?

Reference: Physical Security Assessment for the Department of Veterans Affairs Facilities

13.14
When was the last security assessment performed?
Who performed the security risk assessment?



Reference: DOC CIAO Vulnerability Assessment Framework 1.1

13.15
Are the following areas of security analysis addressed in the security master plan? 
Asset Analysis: Does the security plan identify and prioritize the assets to be protected in accordance to their 
location, control, current value, and replacement value?
Threat Analysis: Does the security plan address potential threats; causes of potential harm in the form of 
death, injury, destruction, disclosure, interruption of operations, or denial of services?(possible criminal acts 
[documented and review of police/security incident reports] associated with forced entry, bombs, ballistic 
assault, biochemical and related terrorist tactics, attacks against utility systems infrastructure and buildings)
Vulnerability Analysis: Does the security plan address other areas associated with the site or building and its 
operations that can be taken advantage of to carry out a threat?(architectural design and construction of new 
and existing buildings, technological support systems [e.g., heating, air conditioning, power, lighting and 
security systems, etc.] and operational procedures, policies, and controls)
Risk Analysis: Does the security plan address the findings from the asset, threat/hazard, and vulnerability 
analyses in order to develop, recommend, and consider implementation of appropriate security 
countermeasures?
This process is the input to the building design and what mitigation measures will be included in the facility project 
to reduce risk and increase safety of the building and people.
Reference: USA TM 5-853, Security Engineerin


Table 1-22: Building Vulnerablilty Assessment Checklist* (continued



*Sources: 
Centers for Disease Control and Prevention/National Institute for Occupational Safety and 
Health (CDC/NIOSH)Publication No. 2002-139, Guidance for Protecting Building 
Environments from Airborne Chemical, Biological, or Radiological Attacks, May 2002
Federal Emergency Management Agency (FEMA)FEMA 154, Rapid Visual Screening of Buildings 
for Seismic Hazards: A Handbook, 1988 (also, Applied Technology Council (ATC-21) by same 
name)
FEMA 386-7, Integrating Human-Caused Hazards Into Mitigation Planning, September 2002
SLG 101, Guide for All-Hazard Emergency Operations Planning, Chapter 6, Attachment G, 
Terrorism, April 2001
General Services Administration (GSA)PBS  P100, Facilities Standards for Public Buildings 
Service, November 2002
Lawrence Berkeley National Laboratory (LBNL)LBNL PUB-51959, Protecting Buildings from a 
Biological or Chemical Attack: Actions to Take Before or During a Release, January 10, 2003
U.S. Air Force (USAF)Installation Force Protection Guide, 1997
U.S. Army (USA)Technical Manuals (TM) 5-853-1/-2/-3/-4, Security Engineering, May 12, 
1994
U.S. Department of Commerce, Critical Infrastructure Assurance Office (DOC 
CIAO)Vulnerability Assessment Framework 1.1, October 1998
U.S. Department of Defense (DoD)Unified Facilities Criteria (UFC), UFC 4-010-01, DoD 
Minimum Antiterrorism Standards for Buildings, July 31, 2002
U.S. Department of Justice (DOJ)National Criminal Justice (NCJ) NCJ181200, Fiscal Year 1999 
State Domestic Preparedness Equipment Program, Assessment and Strategy Development Tool Kit, 
May 15, 2000
U.S. Department of Veterans Affairs (VA)Physical Security Assessment for the Department of 
Veterans Affairs Facilities, Recommendations of the National Institute of Building Sciences Task 
Group to the Department of Veterans Affairs, 6 September 2002






SITE AND LAYOUT DESIGN GUIDANCE     


This chapter discusses site-level considerations for development. The intent of 
this guidance is to provide concepts for integrating land use planning, landscape 
architecture (vegetation, landforms, and water), site planning, and other strategies to 
mitigate the design basis threats as identified via the risk assessment. Integrating 
security requirements into a larger, more comprehensive approach necessitates 
achieving a balance among many objectives such as reducing risk; facilitating proper 
building function; aesthetics and matching architecture; hardening of physical 
structures beyond required building codes and standards; and maximizing use of 
non-structural systems. 
The design community must work closely with building owners and operators to 
ensure that the optimal balance of all the above considerations is achieved; thus, 
coordination within the design team is critical. Many asset protection objectives can 
be achieved during the early stages of the design process when mitigation is the least 
costly and most easily implemented. Planners, architects, and landscape designers 
play an important role in identifying and implementing crucial asset protection 
measures while considering land use; site selection; the orientation of buildings on 
the site; and the integration of vehicle access, control points, physical barriers, 
landscaping, parking, and protection of utilities to mitigate threats. 
It is important to remember that the nature of any threat is always changing. 
Although indications of potential threats may be scarce during the design stage, 
consideration should be given to accommodating enhanced protection measures in 
response to future threats that may emerge. Asset protection objectives must be 
balanced with other design objectives, such as the efficient use of land and resources, 
and must also take into account existing physical, programmatic, and fiscal 
constraints.

2.1 LAND USE CONSIDERATIONS
Managing the many dimensions of land use (e.g., development, transportation, 
activities, and growth, etc.) is a well-established practice in the United States, with 
numerous regulations and other tools in use by state and local governments to 
influence the urban form. These tools range from private controls (e.g., deed 
restrictions and easements) to governmental mechanisms, including permitting, 
subdivision, land development regulations, and zoning. In addition, economic forces 
such as land market values, enterprise zones, insurance costs, tax incentives, and im-
pact fees are major considerations in land use decision-making.
Many of these land use controls are significant factors of antiterrorism and security. 
For example, zoning, subdivisions, and planned unit developments define urban 
configurations, which translate directly into potential terrorist attack opportunities 
because they provide protective clustering of some activities and defensive dispersion 
of others. Furthermore, performance-based zoning (in contrast to prescriptive 
zoning) can allow for greater freedom in land use by removing location-based use 
constraints in favor of simply assigning responsibility for any negative impacts 
directly to the land owner. The benefits of increased performance-based zonings 
flexibility relies on the ability of the owner and/or operator to make informed 
decisions about the level of risk that they are willing to accept and how much risk 
they can mitigate through land use countermeasures.
As another example, a deed restriction limiting the use of an adjacent parcel to open 
space or recreation may present a security advantage in terms of setback, but such 
spaces may also make hostile surveillance and attack preparations difficult to detect 
or to discern from those of normal use. Impact fees on stormwater infrastructure may 
provide an economic incentive to implement low-impact development techniques. In 
addition to reducing infrastructure costs, managing stormwater on site can add 
security through retention facilities that also serve as vehicle barriers and blast 
setbacks. The design of on-site stormwater infrastructure can also reduce the need for 
culverts, drainage pipes, manholes, and other covert site access and weapon 
concealment opportunities.
In some cases, permit and fee waivers can be used to promote public transportation, 
which can reduce urban sprawl and traffic congestion, thus helping to decrease the 
vulnerability of high-risk sites by curbing the flow of traffic and construction of new 
buildings in high-risk areas. Similarly, creation of an overlay zone (sub-zoning to 
address area-specific considerations) based on security requirements could firmly 
establish antiterrorism as a key design consideration, but it could also cause the 
"branding" of an area as dangerous or high risk, thus jeopardizing the success of any 
development nearby. 
Land use tools for antiterrorism and security are generally derivative in nature and 
may not be initially obvious. Typically, land use documents contain a wealth of data 
that can be used to address antiterrorism and security objectives. These sources of 
information, and many more, are available through a variety of channels, including 
city, county, and metropolitan planning offices, emergency management offices, tax 
assessors, councils of governments, and other state and local agencies. 
For land use design, designers should consider external and internal aspects. 
External aspects involve the characteristics of the surrounding area, including 
construction type, occupancies, and the nature and intensity of adjacent activities, as 
well as the implications of these characteristics for the protection of the people, 
property, and operations on the site under consideration. Internal aspects include 
the amount of land available on the site for stand-off and the inherent ability of the 
site to accommodate the implementation of natural and manmade antiterrorism and 
security design features. It is important to recognize that conflicts sometimes arise 
between security-oriented site design and conventional site design. For example, 
open circulation and common spaces (which are desirable for conventional design) 
may be detrimental to certain aspects of security. Designers must balance protection 
priorities with the requirements of the Americans with Disabilities Act Accessibility 
Guidelines (ADAAG), Uniform Federal Accessibility Standards (UFAS), National Fire 
Protection Codes (NFPC), and other applicable building codes and standards. To 
resolve these issues, coordination between the disciplines is critical to the design 
process. 
Whether designing new buildings or evaluating existing ones, the designer should 
evaluate key protection measures to ensure they are appropriate, desirable, and cost-
effective in terms of mitigating the risk of potential terrorist attacks. Security 
measures must be evaluated carefully to understand which measures are truly benefi-
cial and which are not practical. 
When making decisions about site antiterrorism and security, designers should 
consider the following factors:
_ Building footprint(s) relative to total land available
_ Building location(s) or, if undeveloped, suitable building location(s) relative to the 
site perimeter and adjacent land uses; distance between the perimeter fence and 
improved areas off site 
_ Access via foot, road, rail, water, and air; suitability to support a secure perimeter 
_ Current and planned infrastructure and its vulnerabilities, including easements, 
tunnels, pipes, and rights-of-way 
_ Infrastructure nodes that constitute single-point vulnerabilities
_ Adjacent land uses and occupancies that could facilitate attacks or that are potential 
targets themselves and thus present collateral damage or cascading failure hazards 
(see Figure 2-1)
_ Proximity to fire and police stations, hospitals, shelters, and other critical facilities 
that could be of use in an attack
_ Natural hazards, susceptibility to subsidence or liquefaction, and other 
environmental considerations 
_ Presence of natural physical barriers such as water features, dense vegetation, and 
terrain that could provide access control and/or shielding, or suitability of the site 
for the incorporation of such features
_ Topographic and climatic characteristics that could affect the performance of 
chemical agents and other weapons 
_ Observability from outside site boundaries; ability of vegetation in proximity to 
building or site to screen covert activity 

2.2 SITE PLANNING 
The single most important goal in planning a site to resist terrorism and security 
threats is the protection of life, property, and operations. Decision-making in support 
of this purpose should be based first and foremost on a comprehensive assessment of 
the manmade threats and hazards so that planning and design countermeasures are 
appropriate and effective in the reduction of vulnerability and risk. It is important to 
recognize that a given countermeasure can mitigate one or more vulnerabilities, but 
may be detrimental to other important design goals. It is also important to think 
creatively and comprehensively about the security repercussions of common site 
planning and design decisions. This section will highlight several aspects of site 
design and will present some of the unique characteristics arising from their 
application to antiterrorism and security.
2.2.1 Site Design
Because the economics of development dictate recovering the largest possible 
portion of square footage within most urban and rural sites, security concerns should 
be evaluated carefully. Conflicts sometimes arise between security site design and con-
ventional site design. For example, open circulation and common spaces, which are 
desirable for conventional design, are often undesirable for security design. To 
maximize safety, security, and sustainability, designers should implement a holistic 
approach to site design that integrates form and function to achieve a balance 
among the various design elements and objectives. Even if resources are limited, 
significant value can be added to a project by integrating security considerations into 
the more traditional design tasks in such a way that they complement, rather than 
compete with, the other elements.
2.2.2 Layout and Form
The overall layout of a site (e.g., the placement and form of its buildings, 
infrastructures, and amenities) is the starting point for development. Choices made 
during this stage of the design process will steer decision-making for the other 
elements of the site. A number of aspects of site layout and building type present 
security considerations and are discussed below.
_ Building placement. Depending on the site characteristics, the occupancy 
requirements, and other factors, buildings may be clustered tightly in one area, or 
dispersed across the site. Both patterns have compelling strengths and 
weaknesses. Concentrating people, property, and operations in one place creates a 
target-rich environment, and the mere proximity of any one building to any other 
may increase the risk of collateral impacts. Additionally, the potential exists for 
the establishment of more single-point vulnerabilities in a clustered design than 
would exist in a more dispersed pattern. However, grouping high-risk activities, 
concentrations of personnel, and critical functions into a cluster can help 
maximize stand-off from the perimeter and create a "defensible space." This also 
helps to reduce the number of access and surveillance points, and minimize the 
size of the perimeter needed to protect the facilities. Stand-off planning is 
discussed in detail in Sections 2.3 and 2.4. In addition, combining multiple uses 
also provides economic and environmental benefits such as opportunities to 
efficiently transfer heat from net heat-producing areas and activities to net heat-
consuming ones, thus reducing energy costs.In contrast, the dispersal of 
buildings, people, and operations across the site reduces the risk that an attack on 
any one part of the site will impact the other parts. However, this could also have 
an isolating effect, and reduce the effectiveness of on-site surveillance, increase 
the complexity of security systems and emergency response, and create a less 
defensible space.
 To the extent that site, economics, and other factors allow, the designer should 
consolidate buildings that are functionally compatible and have similar threat 
levels (see Figures 2-2 and 2-3). For example, visitor screening areas, 
receiving/loading areas, and mailrooms constitute the innermost line of defense, 
because they may be the first places where people and materials are closely 
inspected before being introduced into the facility. Logically, they should be 
physically separated from the key assets such as main operational areas and 
concentrations of people. It is also desirable to locate potential target buildings 
away from lower-risk areas in order to minimize collateral damage, should an 
attack occur. 
_ Building orientation. The orientation of a building can have significant impact on 
its performance, not only in terms of energy efficiency, but also in the ability to 
protect occupants. For the purposes of this discussion, the term "orientation" 
refers to three distinct characteristics: the buildings spatial relationship to the 
site, its orientation relative to the sun, and its vertical or horizontal aspect relative 
to the ground. 
 A structures orientation relative to its surroundings defines its relationship to that 
area. In aesthetic terms, a building can "open up" to the area or turn its back; it 
can be inviting to those outside, or it can "hunker down" defensively. The physical 
positioning of a building relative to its surroundings may seem subtle, but can be 
a greater determinant of this intangible quality than exterior aesthetics. 
Nevertheless, the proximity of a vulnerable faade to a parking area, street, 
adjacent site, or other area that is accessible to vehicles and/or difficult to observe 
can greatly contribute to its vulnerability. This illustrates one way in which 
protective requirements can be at odds with otherwise good design. A strong, 
blank wall with no glazing will help to protect the people, property, and 
operations within from a blast, but the lack of windows removes virtually all 
opportunity to monitor activities outside and take appropriate protective actions 
in a timely manner. Designers should consider such trade-offs early in the design 
process, in an effort to determine an acceptable level of risk.
 The solar orientation of a building is a significant factor in energy consumption. By 
optimizing the positioning of the building relative to the sun, climate control and 
lighting requirements can be met while reducing power consumption. However, 
these energy conservation techniques present some important security 
considerations. For example, natural ventilation is an effective and time-tested 
technique for efficiently cooling buildings; however, the use of unfiltered outside 
air presents a major vulnerability to aerosolized chemical, biological, and 
radiological agents, in addition to accidental releases of hazardous materials. 
Additionally, awnings may become projectiles in a blast event, and the 
construction of operable windows may not be as blast-resistant as the frames of 
fixed windows. Similarly, the use of light shelves, skylights, clerestories, and atria 
can help meet illumination requirements while dramatically reducing the need 
for electric lighting. However, day lighting relies inherently on the use of glazing, 
which has been shown to be one of the major hazards in blast events. In addition 
to ensuring the maximum setback possible for highly-fenestrated facades, 
designers should ensure that aperture sizes, glazing materials, films, and frames 
and connections are selected with blast-resistance as well as energy efficiency in 
mind.
_ Open space. The incorporation of open space into site design presents a number of 
benefits. First and foremost is the ability to easily monitor an area and detect 
intruders, vehicles, and weapons. Closely related to this benefit is the stand-off 
value of open space; as discussed in Chapter 4, blast energy decreases as the inverse 
of the cube of the distance from the seat of the explosion, so every additional 
increment of distance provides increasingly more protection. In addition, 
pervious open space allows stormwater to percolate back into the ground, 
reducing the need for culverts, drainage pipes, manholes, and other covert site 
access and weapon concealment opportunities. Also, if the open space is 
impassible for vehicles (as in the case of a wetland or densely vegetated area), it 
can provide not only environmental and aesthetic amenities, but prevent vehicle 
intrusion as well.Leaving significant amounts of open space, wetland, or other 
sensitive areas unimproved may present opportunities to reap economic benefits 
in the form of transferable development rights (TDRs). TDR is a market-based 
approach that provides incentives to developers to focus growth only where it is 
desired, making it profitable to refrain from developing open space and sensitive 
areas. By not maximizing the profit potential of their land, owners can receive 
"development right credits" that can be sold to developers elsewhere in the 
community, who will then be able to use those credits to intensify the use of their 
own land in ways that promote more sustainable growth.1  Thus, in some cases, 
TDRs may be a windfall benefit of security-oriented development.
2.2.3 Vehicular and Pedestrian Circulation
The movement of people and materials into, through, and out of a facility is 
determined by the design of its access, circulation, and parking systems. Such systems 
should be designed to maximize efficiency while minimizing conflicts between 
vehicle and pedestrian modes. Designers should begin with an understanding of the 
sites transportation requirements based on an analysis of how the facility will be 
used. This includes studying the number and types of access points that are required, 
the parking volume needed, pedestrian patterns, and the modes of transportation 
they will use. Several aspects of transportation planning can impact security and are 
discussed below.
_ Roadway network design. Streets are generally designed to minimize travel time and 
maximize safety, with the end result typically being a straight path between two or 
more endpoints. Although a straight line may be the most efficient course, 
designers should use caution when orienting streets relative to buildings. Given 
that the energy transferred when one object strikes another is a function of its 
mass and its velocity, a bollard that can stop a 15,000-pound truck moving at 35 
miles per hour may not be able to stop the same truck moving at 55 miles per 
hour. In developing a system of street alignments with protection in mind, the 
designer cannot determine the size or weight of a vehicle that will travel along the 
road, because that is a management decision. However, the designer can propose a 
roadway system to minimize vehicle velocity, thus using the roadway itself as a 
protective measure. This is accomplished through the use of the following 
strategies.First, straight-line or perpendicular approaches to buildings should not 
be used, because these give vehicles the opportunity to gather the speed necessary 
to ram through protective barriers and crash into or penetrate buildings. Instead, 
approaches should be parallel to the faade, with berms, high curbs, appropriate 
trees, or other measures used to prevent vehicles from departing the roadway. A 
related technique for reducing vehicle speeds is the construction of serpentine 
(curving) roadways with tight-radius corners. Existing streets can be retrofitted 
with barriers, bollards, swing gates, or other measures to force vehicles to travel in 
a serpentine path. Again, high curbs and other measures should be installed to 
keep vehicles from departing the roadway in an effort to avoid these 
countermeasures. Less radical than these techniques are traffic calming strategies, 
which seek to use design measures to cue drivers as to the acceptable speed for an 
area. These include raised crosswalks, speed humps and speed tables, pavement 
treatments, bulbouts, and traffic circles. In addition to creating a more pedestrian-
friendly environment, which  increases "eyes on the street" surveillance, designing 
roadways to physically limit speeds can have the added benefits of increasing safety 
and, subsequently, lowering liability. Designers should be aware, however, that 
many of these techniques can have detrimental effects for emergency response, 
including slowing response time, interfering with enroute emergency medical 
treatment, and increasing the difficulty of maneuvering fire apparatus. They also 
may present problems for snow removal, and their outer ends should remain flat 
so that bicycles can proceed unimpeded. Finally, the distinction between speed 
humps, speed tables, and speed bumps is critical. Speed humps and tables are 
much gentler than speed bumps and can be constructed to "enforce" a specific 
speed range. Speed bumps have much more abrupt profiles and are only 
appropriate for low-speed applications, such as parking lots.
_ Parking. There are three primary types of parking facilities, all of which present 
security trade-offs. Surface lots can be designed to keep vehicles away from 
buildings, but they consume large amounts of land and, if constructed of 
impervious materials, can contribute greatly to stormwater runoff volume. They 
can also be hazardous for pedestrians if dedicated pedestrian pathways are not 
provided. In contrast, on-street parking is often convenient for users and a source 
of revenue for local governments, but this type of parking may provide little or no 
setback. Finally, garage structures provide revenue and can be convenient for 
users, but they may require structural measures to ensure blast resistance as well as 
crime prevention measures to prevent street crime. Although the cost of land 
suggests that the construction of a garage below a building (either underground 
or aboveground) may be the most economically viable approach for many 
developments, they can be highly vulnerable to vehicle-borne weapons, 
endangering the building above. If garages must be used, human security 
procedures (e.g., vehicle searches) and electronic systems (e.g., closed circuit 
television) may be necessary to ensure safety (see Section 2.7 for additional 
information). 
2.2.4 Infrastructures and Lifelines
Providing power, gas, water, wastewater, and communications services is one of the 
most basic requirements of any development. At the site scale, all critical lifelines 
should have at least one layer of redundancy, or backup. By eliminating single-point 
vulnerabilities,  designers reduce the chance that service will be interrupted if an 
attack damages or destroys a lifeline either outside the perimeter or on site. It is 
important to note that collocating a backup lifeline with its primary lifeline does not 
eliminate single-point vulnerability; only physical separation can substantially 
increase the likelihood of continuity of service. Designers should be aware that this 
could create the need for each type of infrastructure lifeline to cross the site 
perimeter at multiple locations, potentially complicating the process of managing 
utility easements and rights-of-way. Additional information on critical systems is also 
discussed in Chapter 3.
Additionally, all controls, interconnections, exposed lines, and other vulnerable 
elements of infrastructure systems should be protected from access and exploitation 
by surveillance and/or physical countermeasures. Service entrances and other 
secondary access points should be monitored and access-controlled; special attention 
should also be paid to any locations where multiple systems or primary and backup 
systems come together, such as control rooms and mechanical spaces. Again, these 
facilities should be designed for maximum observability, including the use of 
opportunity reduction and target hardening strategies where appropriate, and should 
be equipped with adequate lighting and emergency communications capabilities 
wherever possible.  
2.2.5 Landscape and Urban Design
Designing to meet user needs while maintaining stewardship of the natural and built 
environments becomes increasingly more challenging when security requirements 
are factored in. Design principles should include an emphasis on mixed-use 
development; selection of low-impact development techniques and environmental 
stewardship; compatibility of context and relationship with adjacent uses, forms, and 
styles; establishment of scale and identity through aesthetic design; connectivity 
among buildings, uses, activities, and transportation modes; resource conservation; 
cultural responsiveness; and the creation of appealing public spaces. These objectives 
are generally achieved through the work of two closely related disciplines, landscape 
design and urban design. For the purposes of this document, these two domains are 
virtually overlapping and will, therefore, be addressed together.
_ Landscape design. The implications of security for landscape design affect 
everything from plant species and building material selection to landform 
construction and wayfinding. Elements such as landforms, water features, and 
vegetation are among the building blocks of attractive and welcoming spaces, and 
they can also be powerful tools for enhancing security. These features can be used 
not only to define or designate a space, but also to deter or prevent hostile 
surveillance and unauthorized access. Vegetative groupings and landforms can 
even provide some level of blast shielding. Stands of trees, earthen berms, and 
similar countermeasures generally cannot replace setbacks, but they can offer 
supplementary protection. However, landscaping can also have detrimental 
impacts for safety and security, and practitioners should consider the unique 
requirements of the project to ensure that the landscape design elements they 
choose will be appropriate and effective. For example, thorn-bearing and sharp-
leaved plant species (e.g., firethorn, Spanish bayonet, and pampas grass) can 
create natural physical barriers to deter aggressors. Although this technique can 
be highly effective, designers should consider the liability they may incur from 
injuries resulting from legitimate users inadvertently coming into contact with 
them. Additionally, although such plants can provide security for ground-level 
windows, they may also impede emergency egress.With careful selection, 
placement, and maintenance, landscape elements can provide visual screening 
that protects sensitive operations, gathering areas, and other activities from 
surveillance without creating concealment for covert activity. However, dense 
vegetation in close proximity to a building can screen illicit activity and should be 
avoided. Additionally, thick ground cover such as English ivy or vegetation over 4 
inches tall such as monkey grass can be used to conceal bombs and other 
weapons; in setback clear zones, vegetation should be selected and maintained 
with eliminating concealment opportunities in mind. Similarly, measures to 
screen visually detractive components such as transformers, trash compactors, and 
condensing units should be designed to minimize concealment opportunities for 
people and weapons.
_	Urban design. Through urban design, practitioners seek to create vibrant, inviting, 
and functional places for people to live, work, and play. To protect people, 
property, and operations, and to reduce liability, security should be considered a 
necessary aspect of these characteristics. If people do not feel safe, they will not use 
a place and, if a place is not used as intended, it will fail to fulfill its purpose. This 
failure can, in turn, result in a net loss to the community in terms of social, 
economic, and environmental sustainability. Numerous urban design elements 
present opportunities to provide security. The scale of the streetscape should be 
appropriate to its primary users, and it can be manipulated to increase the comfort 
level of desired users while creating a less inviting atmosphere for users with 
malicious intent. However, even at the pedestrian scale, certain operational 
requirements must be accommodated. For example, although efficient pedestrian 
and vehicle circulation systems are important for day-to-day living, they are also 
critical for emergency response, evacuation, and egress. Furthermore, despite an 
emphasis on downsizing the scale of the streetscape, it is critical to maintain the 
maximum stand-off distance possible between vehicles and structures. At the site 
perimeter, walls and fences used for space definition may be hardened to resist the 
impact of a weapon-laden truck; however, planters, bollards, or decorative boulders 
could accomplish the same objective in a much more aesthetically pleasing 
manner. Such an approach also creates permeability, which would allow 
pedestrians and cyclists to move more easily through the space. Additional 
information on protective barriers is included in Section 2.4.1.
 Similarly, street furniture (e.g., mailboxes, bus stop shelters, light poles, works of art, 
street trees, planters, bicycle racks, seating, newspaper boxes, kiosks, and trash 
receptacles) can be used to enhance security (see Figure 2-4). For example, bus 
stop shelters can be designed to allow for easy surveillance and detection of 
suspicious activity and objects. Hardened versions of everyday items, such as light 
poles, planters, benches, street trees (of appropriate size and type), and even water 
fountains can serve as vehicle barriers. These items maintain stand-off while 
creating a line of protection that is virtually transparent and highly permeable at 
the pedestrian scale. Note that in-ground installation of bollards, fences, and any 
other anti-ram measures should be preceded by an assessment of soil conditions 
and underground utilities in the immediate vicinity.
A main challenge for the design community is to reach the desired level of 
protection without turning the building or facility into a bunker or fortress. In other 
words, they are required to incorporate subtle and aesthetically pleasing security 
measures when involved in urban design projects. Below are some rules of thumb that 
should be taken into consideration when designing an urban landscape with a 
security component:
_ Security measures must not impede access to public entrances or pedestrian flow on 
adjacent sidewalks.
_ Landscape elements in the form of grassed plinths, trees, plantings, fountains, and 
pools are appropriate, but must be designed as integral parts of a building and its 
setting as much as possible.
_ Miscellaneous decorative elements such as flag poles, fountains, pools, gardens, 
and similar features may be located within an accessway to slow movement or 
restrict access.
_ Trees planted along the inside edge of a public sidewalk and adjacent to pedestrian 
and vehicular accessways can serve dual aesthetic and barrier purposes.
_ The design of bollards, fences, light posts, and other streetscape and landscape 
elements should form an urban ensemble that helps to create a sense of unity and 
character.
_ Security devices must be designed and located to establish consistent, rhythmic 
patterns along the street, particularly where a number of elements are used in 
combination to reduce visual street clutter.
_ Security devices must not obstruct pedestrian movement or access by emergency 
vehicles; therefore, the use of bollards, posts, and chains may be inappropriate 
when this function is required. 
No discussion of using landscape and urban design for security would be complete 
without a discussion of design-oriented crime prevention strategies such as Crime 
Prevention Through Environmental Design (CPTED). This approach to design is 
based on evidence that the design and form of the built environment can influence 
human behavior. Specifically, CPTED seeks to create a physical environment that 
discourages criminal activity by incorporating territoriality cues, natural access 
controls, natural surveillance, support for legitimate activities, and ongoing property 
maintenance into landscape and urban design. Section 2.12 is a brief overview of 
CPTED. Closely related to, but not synonymous with, CPTED is situational crime 
prevention. This approach encompasses many CPTED principles; however, it focuses 
on managerial and user behavior factors that affect opportunities for criminal 
behavior in a specific setting for a specific crime, whereas CPTED focuses on 
changing the physical design aspects of environments to deter criminal activity. 
More akin to CPTED is the defensible space approach, in which the emphasis is on 
structuring the physical layout of space so that its residents are able to establish a 
sense of ownership and control over common areas in the community. Both of these 
proactive approaches to crime prevention have merit; designers should carefully 
evaluate the unique requirements of each design problem to identify the most 
appropriate strategy.
Landscape and urban design inherently define the "line of sight" in a space. 
Operational security is not a traditional element of master planning, but managing 
the threat of hostile surveillance is a significant consideration in protecting people, 
property, and operations. These techniques seek to deny aggressors a "line of sight" 
to a potential target, either from on or off site. This increases the protection of 
sensitive information and operations by using stand-off weapons (see Figures 2-5 and 
2-6). In addition to the use of various screening options, anti-surveillance measures 
(e.g., building orientation, landscaping, screening, and landforms) can also be used 
to block sight lines. 
Depending on the circumstances, landforms can be either beneficial or detrimental 
to anti-surveillance. Elevated sites may enhance surveillance of the surrounding area 
from inside the facility, but may also allow observation of on-site areas by adversaries. 
Buildings should not be sited immediately adjacent to higher surrounding terrain, 
unsecured buildings owned by unfamiliar parties, or vegetation, drainage channels, 
ditches, ridges, or culverts that can provide concealment. For high-risk buildings, it 
may be necessary to provide additional protection by creating a clear zone 
immediately adjacent to the structure that is free of all visual obstructions or 
landscaping (see Figure 2-7). The clear zone facilitates monitoring of the immediate 
vicinity and visual detection of attacks. Walkways and other circulation features 
within a clear zone should be located so that buildings do not block views of pe-
destrians and vehicles. If clear zones are implemented, it may be necessary to 
implement other anti-surveillance measures.
2.3 STAND-OFF DISTANCE   
Many different measures can be used to provide site design protection. Distance is the 
most effective and desirable tool because other measures vary in effectiveness, are 
more costly, and often have unintended consequences. For example, a blast wall can 
become the source of fragmentation if an explosion occurs in close proximity to it. 
The most cost-effective solution for mitigating explosive effects is to ensure the 
explosions occur as far away from the buildings as possible. Stand-off distance and 
the effects of blast are discussed in Section 4.2.
The distance between an asset and a threat is referred to as the stand-off distance, as 
shown in Figure 2-8. There is no ideal stand-off distance; it is determined by the type 
of threat, the type of construction, and desired level of protection. The primary 
design strategy is to keep terrorists away from inhabited buildings (see Figure 2-9). 
Although sufficient stand-off distance is not always possible in conventional 
construction, maximizing the distance may be the most cost-effective solution. 
Maximizing stand-off distance also ensures that there is opportunity in the future to 
upgrade buildings to meet increased threats or to accommodate higher levels of 
protection. Stand-off distance must be coupled with appropriate building hardening, 
as discussed in Chapters 3 and 4, to provide the necessary level of protection to assets. 
Considerations for stand-off distance are as follows:
_ The first mode of site protection is to create "keep out zones" that can ensure a 
minimum guaranteed distance between an explosion (e.g., from a vehicle) and the 
target structure. 
_ The perimeter line is the outermost line that can be protected by the security 
measures incorporated during the design process. It is recommended that the 
perimeter line be located as far as is practical from the building exterior. Many 
vulnerable buildings are located in urban areas where only the exterior wall of the 
building stands between the outside world and the building occupants. In this 
case, the options are obviously limited. Often, the perimeter line can be pushed 
out to the edge of the sidewalk by means of bollards, planters, and other obstacles, 
as discussed earlier in this chapter. To push this line even further outward, 
restricting or eliminating parking along the curb often can be coordinated with 
local authorities. In some extreme cases, elimination of loading zones and the 
closure of streets are an option.
_ "Keep out zones" can be achieved with perimeter barriers that cannot be 
compromised by vehicular ramming. A continuous line of security should be 
installed along the perimeter of the site to protect it from unscreened vehicles and 
to keep all vehicles as far away from critical assets as possible.
_ When selecting a site for a building, consider its location relative to the site 
perimeter. Maximize the distance between the perimeter fence and developed 
areas, providing as much open space as possible inside the fence along the site 
perimeter.
_ The following critical building components should be located away from main 
entrances, vehicle circulation, parking, and maintenance areas. If this is not 
possible, harden as appropriate:
  Emergency generator, including fuel systems, day tank, fire sprinkler, and 
water supply
  Normal fuel storage
  Telephone distribution and main switchgear
  Fire pumps
  Building control centers
  UPS systems powering critical functions
  Main refrigeration systems if critical to building operation
  Elevator machinery and controls
  Shafts for stairs, elevators, and utilities
  Critical distribution feeders for emergency power
2.4CONTROLLED ACCESS ZONES
One method to attain the appropriate level of protection and ensure stand-off 
distance between assets and potential threats is with the creation of a controlled 
access zone. These zones attempt to limit access to the area immediately surrounding 
a building. Access to a controlled zone can be restricted by the installation of a 
physical barrier. Although a controlled access zone is one of the best methods of 
providing stand-off, such issues as site limitations, building siting, and property line 
restrictions do not always allow this zone to be created. For additional references, see 
building placement information in Section 2.2.2.
For high-risk building sites, there is a broad range of "controlled access" elements in 
security design. Controlled access may range from a complete physical perimeter 
barrier (full control), to relatively minimal anti-vehicle protection with full 
pedestrian access, to simply monitoring the perimeter with electronic means.
A good way to ensure appropriate stand-off distance is by establishing controlled 
zones. These zones define minimum distances between assets and potential threats 
through the installation of barriers (such as bollards, planters, fountains, walls, and 
fences), as explained in Section 2.2.5. The barriers are designed to withstand assaults 
by terrorist vehicles; however, their placement must be designed to allow for access by 
fire and rescue vehicles in the event of an emergency. Selection of barriers is based 
on operational considerations related to vehicle access and parking. Good design 
principles for high-risk buildings endorse the complete surround of a building with 
a stand-off zone that has perimeters set at distances that consider threat levels, 
desired level of protection, building construction, and land availability. Entry into a 
controlled area should only be through an entry control point.
Controlled access zones may be exclusive or non-exclusive, as shown in Figure 2-10. 
An exclusive zone is the area surrounding a building within the exclusive control of 
the building. Anyone entering an exclusive zone must have a purpose related to the 
building. A non-exclusive zone is either a public right-of-way or an area related to 
several buildings. Someone entering a non-exclusive zone could be headed for any 
building within that area. Public access areas outside a downtown building would 
typically be considered non-exclusive. As explained previously, these measures may 
not be applicable for all buildings. They are intended for those who need security 
measures due to their function or location.
2.4.1Physical Protective Barriers
A physical barrier is a means of establishing a controlled access area around a 
building or asset. Physical barriers can be used to define the physical limits of a 
building or campus and can help to restrict, channel, or impede access and 
constitute a continuous obstacle around the site. Physical barriers can create a 
psychological deterrent for anyone planning an unauthorized entry and they can 
delay or prevent passage into a site. This is especially true of barriers against forced 
entry by vehicles. The type of barriers utilized can have a direct impact on the number 
and type of security posts that may be needed to ensure site security. Utility areas 
(such as water sources, transformer banks, commercial power and fuel connections, 
heating and power plants, or air conditioning units) may require these barriers for 
safety standards. 
As explained in Section 2.2.5, a number of elements may be used to create a physical 
barrier, some natural and some manmade. Natural barrier elements include rivers, 
lakes, waterways, steep terrain, mountains, barren areas, plants, and other terrain 
features that are difficult to traverse. Manmade elements include fencing, walls, 
buildings, bollards, planters, concrete barriers, and fountains. Selection of elements 
must consider the level of security desired and the type of threat most likely to occur. 
Some perimeter security elements are shown in Figure 2-11.
Fencing is a common means of establishing a physical protective barrier to protect a 
controlled area. The type of fencing used depends primarily on the threat and the 
degree of permanence. It may also depend on the availability of materials and the 
time needed for construction. Fencing may be erected for other uses besides 
impeding personnel access, such as obstructing views, serving as a means to defeat 
stand-off weapon systems (e.g., rocket-propelled grenades), and serving as a barrier to 
hand-thrown weapons (e.g., grenades and firebombs).
Fencing may be used to augment or increase the security of existing barriers that 
protect restricted areas. Examples include the creation an additional barrier line and 
an increase in the existing fence height. It is important to recognize that fencing 
provides very little delay when it comes to motivated aggressors, but it can act as a 
psychological deterrent when an aggressor is deciding which building to attack. The 
following are commonly used fencing types:
_ Chain-link. Generally, chain-link fencing is used for protecting permanent limited 
and exclusion areas. Chain-link fence (including gates) is typically 6-foot high 
fence fabric, mounted on steel poles that may include a top guard or outrigger. 
Chain-link fences are usually 9-gauge or heavier, galvanized wire with mesh 
openings not larger than 2 inches per side and have twisted and barbed selvages at 
the top and the bottom. 
_ Anti-climb (CPTED) fence. Although different styles of anti-climb fences are 
available, most consist of vertical bars with horizontal supports designed to make 
climbing difficult.
_ Barbed wire. Standard barbed wire is twisted, double-strand wire, with four-point 
barbs spaced an equal distance apart along the strand. Barbed wire fencing 
(including gates) intended to prevent human trespassing should not be less than 
6 feet high and must be affixed firmly to posts not more than 6 feet apart. Barbed 
wire may be used as a top guard or outrigger on a standard chain-link fence.
_ Barbed tape or concertina. A barbed taped obstacle fabricated from 0.025-inch 
stainless steel tape with barbed clusters. Barbed tape can be deployed, tangle-free, 
for fast installation without supporting fence posts. 
_ Triple-standard concertina wire. This type of fence uses three rolls of stacked 
concertina; one roll is stacked on top of two other rolls that run parallel to each 
other while resting on the ground, forming a pyramid. This fence has been used 
effectively in lieu of a chain-link fence. 
_ Tangle-foot wire. Tangle-foot wire is an obstruction fence constructed of barbed 
wire or tape set up outside a single perimeter fence or in the area between double 
fences to provide an additional deterrent to intruders. Wire or tape is supported on 
short metal or wooden pickets spaced at irregular intervals of 3 to 10 feet and at 
heights between 6 and 12 inches. The wire or tape should be criss-crossed to 
provide a more effective obstacle. The space and materials available govern the 
depth of the field. Liability issues should be considered when installing a tangle-
foot wire.
_ Cable. Cable or wire rope can be used as a separate, temporary barrier or it may be 
attached to chain-link or anti-climb fences to provide additional crash resistance.
When necessary, a top guard should be installed on all perimeter fences and may be 
added to interior enclosures for additional protection. A top guard is an overhang of 
barbed wire or tape along the top of a fence, facing outward and upward at 
approximately a 45-degree angle. Placing barbed wire or tape above it can further 
enhance the top guard. Top guard supporting arms are permanently affixed to the 
top of fence posts and increase the overall height of the fence. Three strands of 
barbed wire spaced 6 inches apart must be installed on the supporting arms. (Due to 
liability issues in some locations, the top guards will not be allowed to face outward 
where the fence is adjacent to public areas.)
Clear zones should be maintained on both sides of the perimeter barrier to provide 
an unobstructed view of the barrier and the ground adjacent to it. A clear zone of 20 
feet or more should exist between the perimeter barrier and exterior structures, 
parking areas, and natural or manmade features. When possible, a clear zone of 50 
feet or more should exist between the perimeter barrier and structures within the 
protected area, except when the wall of a building constitutes part of the perimeter 
barrier. Roads within the clear zone should be as close to the perimeter barrier as 
possible without interfering with it. The roads should be constructed to allow 
effective road barriers to deter motor movement of unauthorized personnel. When 
barriers enclose a large area, a perimeter road should be provided for security patrol 
vehicles on the interior.
Fences may be augmented with additional security systems, such as motion sensors 
and closed circuit camera systems.
Because barriers can be compromised through breaching (cutting a hole through a 
fence) or by nature (berms eroded by the wind and rain), they should be inspected 
and maintained at least weekly. Security personnel should look for signs of deliberate 
breaches, holes in and under barriers, natural debris building up against barriers, 
and the proper functioning of locks.
2.4.2 Other Perimeter Barriers
The exterior of a building may form a part of a perimeter barrier. Brick or block 
masonry or cast in place concrete walls may act as part of a perimeter barrier. They 
must be at least 7 feet high and should have a barbed wire top guard, depending on 
the threat and application. The windows, active doors, and other designated 
openings should be protected with fastening bars, grilles, or chain-link screens, and 
window barriers should be fastened from the inside. If hinged, the hinges and locks 
must be on the inside to facilitate emergency egress. 
Barrier walls designed to resist the effects of an explosion can, in some cases, act to 
reduce the pressure levels acting on the exterior walls of buildings. They may not, 
however, enhance security because they prohibit observation of activities occurring 
on the other side of the wall. In this case, a plinth wall (anti-ram knee wall) with a 
fence may be an effective solution to combine anti-ram capability and observation.
Consideration should also be given to the improvement of a defensive posture should 
threat levels increase. A number of temporary or semi-permanent measures may be 
effective. Expedient methods include blocking access routes with heavy vehicles or 
temporarily blocking roads surrounding a building to create a form of controlled 
access area. Figure 2-12 is an example of closing streets to restrict access around a 
building.
Typically, street closures exclude vehicles, but allow access by pedestrians with proper 
credentials. The use of street closures must be balanced against minimum 
circulation/access requirements and fire protection considerations.
If a secured area requires a limited exclusion area on a temporary or infrequent basis, 
it may not be possible to use physical structural barriers. A limited exclusion area may 
be established with additional security posts, patrols, and other security measures 
during the period of restriction. Temporary barriers (including temporary fences, 
jersey barriers, and vehicles) may also be used. 
2.4.3Anti-ram Vehicle Barriers
Vehicle barriers are a traditional anti-ram solution that prevents vehicle access for 
pedestrian protection and building security. Vehicle barriers are considered either 
passive barriers, which are stationary (e.g., fixed bollards, concrete walls, planters, 
berms), or active barriers, which can typically be retracted or moved out of the way to 
allow passage (such as retractable bollards, crash beams, and rotating plates). Passive 
barriers are used to create perimeter or edge protection; active barriers are applicable 
to roadways, driveways, or entry control points where they can be lowered or raised to 
prevent passage.
Passive barriers typically consist of bollards, which are concrete filled steel pipes that 
can be placed every few feet along the curb of a sidewalk to prevent vehicle intrusion 
(see Figure 2-13). In order to resist the impact of a vehicle, the bollard needs to be 
fully embedded into a concrete strip foundation that is several feet deep. The height 
of the bollard above ground should be higher than the bumper of the vehicle, 
typically 39 to 40 inches. The spacing of the bollards is based on several factors, 
including Americans with Disabilities Act (ADA) requirements, the minimum width 
of a vehicle, and the number of bollards required to withstand the impact. As a rule of 
thumb, the center to center spacing should be between 3 and 5 feet to be effective. 
The foundation should be designed according to site soil conditions.
An alternative to a bollard is a plinth wall, which is a continuous low wall constructed 
of reinforced concrete with a buried foundation. The bollard or plinth wall is 
designed by equating the kinetic energy of the vehicle at impact with the strain 
energy absorbed by the barrier and the vehicle. 
The foundation of the bollard and plinth wall system can present challenges. For 
effectiveness, the barriers need to be placed as close to the curb as possible. The 
property line of buildings often does not extend to the curb. Therefore, a permit may 
be required by the local authorities to place barriers with foundations near the curb. 
To avoid this, building owners are often inclined to place bollards along the property 
line, which significantly reduces the effectiveness of the barrier system because it 
reduces the stand-off distance. Sometimes a basement may exist below the pavement 
that extends to the property line. Embedding a barrier foundation into the basement 
foundation wall or through the basement roof may introduce water infiltration issues 
and structural foundation design complications. 
Another problem that can arise is below ground utilities that may be close to the 
pavement surface. Their exact location along the length of the perimeter may not be 
known. This can be a strong deterrent to selecting barriers with foundations as a 
solution. For high-risk buildings, it is recommended that these issues be resolved so 
that a proper anti-ram solution is worked out and installed. 
For lower-risk buildings without straight-on vehicular access, it may be more 
appropriate to install surface mounted systems, such as planters, or use landscaping 
features to deter an intrusion threat. An example of a simple, but effective, 
landscaping solution is to install a wide permanent planter around the building with 
a wall that is as high as a car or truck bumper. Individual planters mounted on the 
sidewalk resist impact through inertia and friction between the planter and the 
pavement. It can be expected that the planter will move as a result of the impact. 
Furthermore, to reduce displacement, the planter may be positioned several inches 
below the pavement surface. A roughened, grouted surface also will improve 
performance. The objective is to keep the displacement less than the building 
setback.
In high security sites and at points where access must be provided through an anti-
ram perimeter, active or operational anti-ram systems are required. Off-the-shelf 
products are available that are rated to resist various levels of car and truck impacts 
(see Figure 2-14). Solutions include crash beams, crash gates, surface mounted plate 
systems, retractable bollards, and rotating wedge systems. 
The following are some security considerations for sites requiring security measures 
(see also Sections 2.4.1 and 2.4.2):
_ Design and select barriers based on threat capabilities. 
_ If the limited availability of land precludes the creation of an exclusive zone, the use 
of screening surrounding the building is an alternative. 
_ Use a combination of barriers. Some barriers are fixed and obvious (fences and 
gates), while others are passive (sidewalks far away from buildings, curbs with 
grassy areas, etc.). 
_ Where physical barriers are required, consider using landscape materials to create 
barriers that are soft and natural rather than manmade.
_ Vehicles can be used as temporary physical barriers if they are placed in front of 
buildings or across access roads.
_ Maintain as much stand-off distance as possible between potential vehicular bombs 
and the building:
  Provide traffic obstacles near entry control points to slow down traffic. 
  Consider vehicle barriers at building entries and drives. 
  Offset vehicle entrances from the direction of a vehicles approach to force a 
reduction in speed.
  When possible, position gates and perimeter boundary fences outside the 
blast vulnerability envelope.
  If the threat level warrants, provide a vehicle crash resistance system in the 
form of a low wall or earth berm.
_ Provide passive vehicle barriers to keep stationary vehicle bombs at a distance from 
the asset.
  Use high curbs, low berms, shallow ditches, trees, shrubs, and other physical 
separations to keep stationary bombs at a distance. 
  Do not allow vehicles to park next to perimeter walls of the secured area. 
Consider using bollards or other devices to keep vehicles away. 
2.5ENTRY CONTROL AND VEHICULAR ACCESS
If a perimeter barrier is employed, it will be necessary to provide points of access 
through the perimeter for building users (i.e., employees, visitors, and service 
providers). An entry control point or guard building serves well as the designated 
point of entry for site access. It provides a point for implementation of 
desired/required levels of screening and access control; an example is shown in 
Figure 2-15. The objective of the entry control point is to prevent unauthorized access 
while maximizing the rate of authorized access by foot or vehicle. These measures are 
not required for all sites and buildings; they are only required for those considered at 
high risk.
Location selection for vehicular access and entry control for a building starts with an 
evaluation of the anticipated demand for access to the controlled site. An analysis of 
traffic origin and destination, and an analysis of the capability of the surrounding 
connecting road network, including its capacity to handle additional traffic, should 
then be performed. Expansion capacity should also be considered. The analysis 
should be coordinated with the state and local departments of transportation.
The existing terrain can have a significant impact on the suitability of a potential 
entry control point site. Flat terrain with no thick vegetation is generally preferred. A 
gentle rise in elevation up to the entry control guard building allows for a clear view 
of arriving vehicles. Consider how existing natural features such as bodies of water or 
dense tree stands may enhance perimeter security and vehicle containment. Entry 
control spatial requirements vary, depending on the type, the traffic demand, and the 
necessary security measures.
In commercial buildings or campuses, more than one type of entry may be required 
to accommodate the three basic types of traffic (site personnel, visitors, and 
commercial traffic). Active perimeter entrances should be designated so that security 
personnel can maintain full control without creating unnecessary delays in traffic. 
This could be accomplished with a sufficient number of entrances to accommodate 
the peak flow of pedestrian and vehicular traffic, and adequate lighting for rapid and 
efficient inspection. Some entrances may be closed during non-peak periods, and 
should be securely locked, illuminated during hours of darkness, and inspected 
periodically. Additionally, warning signs should be used to warn drivers when gates 
are closed. Doors and windows on buildings that form a part of the perimeter should 
be locked, lighted, and inspected regularly. 
The following measures should be considered in the design of entry control points:  
_ Design entry roads to sites and to individual buildings so that they do not provide 
direct or straight-line vehicular access to high-risk buildings. Route major 
corridors away from concentrations of high-risk buildings.
_ Design access points at an angle to oncoming streets so that it is difficult for a 
vehicle to gain enough speed to break through the stations. 
_ Minimize the number of access roads and entrances into a building or site.
_ Designate entry to the site for commercial, service, and delivery vehicles, preferably 
away from high-risk buildings whenever possible.
_ Design the entry control point and guard building so that the authorization of 
approaching vehicles and occupants can be adequately assessed, and the safety of 
both gate guards and approaching vehicles can be maintained during periods of 
peak volume. 
_ Approach to the site should be designed to accommodate peak traffic demand 
without impeding traffic flow in the surrounding road network.
_ Provide pull-over lanes at site entry gates to check suspect vehicles. When necessary, 
provide a visitor/site personnel inspection area to check vehicles prior to allowing 
access to a site or building.
_ Design active vehicle crash barriers (e.g., road alignment, retractable bollards, 
swing gates, or speed bumps) as may be required to control vehicle speed and slow 
incoming vehicles to give entry control personnel adequate time to respond to 
unauthorized activities.
_ Design the inspection area so that it is not visible to the public, when necessary. 
Place appropriate landscape plantings to accomplish screening.
_ Consider current and future inspection technologies (e.g., above vehicle and under 
vehicle surveillance systems, ion scanning, and x-ray equipment).
_ Provide inspection bays that can be enclosed to protect inspection equipment in 
the event of bad weather.
_ Design inspection areas that are large enough to accommodate a minimum of one 
vehicle and a pull-out lane. They should also be covered and capable of 
accommodating the inspection of the undercarriage plus overhead inspection 
equipment. 
_ If space is available, provide traffic queuing for vehicles needing authorization.  
_ Consider providing a walkway and turnstile for pedestrians and a dedicated bicycle 
lane.  
_ If possible, provide a gatehouse for the workstations and communications 
equipment of the security personnel. It may also serve as a refuge in the event of an 
attack.
_ Provide some measure of protection against hostile activity if ID checking is 
required between the traffic lanes.
_ For high security buildings, provide a final denial barrier to stop unauthorized 
vehicles from entering the site. Most individuals who may attempt to enter without 
authorization are lost, confused, or inattentive, but there are also those whose 
intent may be to "run the gate." A properly designed final denial barrier will take 
into account both groups, safely stopping the individuals who have made an 
honest mistake, but providing a properly designed barrier to stop those with 
hostile intentions.
_ Design the barrier system to impede both inbound and outbound vehicles. The 
system should include traffic control features to deter inbound vehicles from 
using outbound lanes for unauthorized access. Barrier devices that traverse both 
roadways should be included in the design. The safety features discussed above for 
inbound lanes should also be provided in the outbound lanes.
2.6SIGNAGE
Wayfinding is an important function of design that illustrates the importance of 
coordination among practitioners and community planning, public works, 
transportation, law enforcement, and fire-rescue organizations. The ability of users to 
navigate an unfamiliar environment is important for its success on a day-to-day basis, 
but will become critical in an emergency situation. In addition to overt prompts such 
as landmarks, architectural elements, and clear, consistent signage and maps, users 
will subconsciously rely on cues from their surroundings to help them select a path 
to safety. Similarly, emergency responders will depend in part on these design 
elements in order to navigate the scene.
Signs are an important element of security. They are meant to keep intruders out of 
restricted areas; however, inadequate signs can create confusion and defeat their 
primary purpose. Confusion over site circulation, parking, and entrance locations 
can contribute to a loss of site security. Signs should be provided off site and at 
entrances. There should be on-site directional, parking, and cautionary signs for 
visitors, employees, service vehicles, and pedestrians. Unless required, signs should 
not identify sensitive areas. A comprehensive signage plan should include the 
following:
_ Prepare signs for each entry control building. 
_ Prepare entry control procedures signs, which explain current entry procedures for 
drivers and pedestrians.
_ Prepare traffic regulatory and directional signs, which control traffic flow and 
direct vehicles to specific appropriate points.
_ Consider using street addresses or building numbers instead of detailed descriptive 
information inside the site.
_ Minimize the number of signs identifying high-risk buildings; however, a 
significant number of warning signs should be erected to ensure that possible 
intruders are aware of entry into restricted areas. 
_ Minimize signs identifying critical utility complexes (e.g., power plants and water 
treatment plants). Post clear signs to minimize accidental entry by unauthorized 
personnel into critical asset areas.
_ Install warning signs that are easy to understand along the physical barriers and at 
each entry point.
_ Warning signs must use both (or more) languages in areas where two or more 
languages are commonly spoken. The wording on the signs should denote 
warning of a restricted area. The signs should be posted at intervals of no more 
than 100 feet and should not be mounted on fences equipped with intrusion-
detection equipment. Additionally, the warning signs should be posted at all 
entrances to limited, controlled, and exclusion areas. 
_ Locate variable message signs, which give information on site/organization special 
events and visitors, far inside site perimeters.
2.7PARKING
Parking restrictions can help to keep potential threats away from a building. In urban 
settings, however, curbside or underground parking is often necessary and 
sometimes difficult to control. Mitigating the risks associated with parking requires 
creative design measures, including parking restrictions, perimeter buffer zones, 
barriers, structural hardening, and other architectural and engineering solutions. 
Operational measures may also be necessary to inspect or screen vehicles entering 
parking garages. The following considerations may help designers to implement 
sound parking measures for buildings that may be at high risk:
_ Locate vehicle parking and service areas away from high-risk buildings to minimize 
blast effects from potential vehicle bombs.
_ Restrict parking from the interior of a group of buildings.
_ If possible, locate visitor or general public parking near, but not on, the site itself. 
_ Restrict parking within the secured perimeter of an asset from unauthorized 
personnel. 
_ Locate general parking in areas that present the fewest security risks to personnel. 
_ If possible, design the parking lot with one-way circulation to facilitate monitoring 
for potential aggressors. 
_ Locate parking within view of occupied buildings. 
_ Prohibit parking within the stand-off zone. 
_ When establishing parking areas, provide emergency communication systems (e.g., 
intercom, telephones, etc.) at readily identified, well-lighted, closed circuit 
television monitored locations to permit direct contact with security personnel.
_ Provide parking lots with closed circuit television cameras connected to the security 
system and adequate lighting capable of displaying and videotaping lot activity. 
_ Request appropriate permits to restrict parking in curb lanes in densely populated 
areas to company-owned vehicles or key employee vehicles.
_ Provide appropriate setback from parking on adjacent properties if possible. 
Structural hardening may be required if the setback is insufficient. In new designs, 
it may be possible to adjust the location of the building on the site to provide 
adequate setback from adjacent properties.
_ If possible, prohibit parking beneath or within a building.
_ If parking beneath a building is unavoidable, limit access to the parking areas and 
ensure they are secure, well-lighted, and free of places of concealment.
_ Do not permit uninspected vehicles to park under a building or within the exclusive 
zone. If parking within the building is required, the following restrictions may be 
applied:
  Public parking with ID check
  Company vehicles and employees of the building only
  Selected company employees only, or those requiring security
_ Apply the following when parking inside a building is necessary and the building 
superstructure is supported by the parking structure:
  Protect primary vertical load carrying members by implementing 
architectural or structural features that provide a minimum 6-inch stand-off 
from the face of the member.
  Design columns in the garage area for an "unbraced length" equal to two 
floors, or three floors where there are two levels of parking.
_ For all standalone, aboveground parking garages, maximize visibility for 
surveillance  into, out of, and across the garage.
_ Employ express or non-parking ramps, sending the user to parking on flat surfaces.
_ Avoid dead-end parking areas, as well as nooks and crannies.
_ Design landscaping that does not provide hiding places. It is desirable to locate 
plantings away from parking garages and parking lots to permit observation of 
pedestrians.
Additional parking considerations include:
_ Stairways and elevator lobby design should be as open as code permits. The ideal 
solution is a stair and/or elevator waiting area totally open to the exterior and/or 
the parking areas. Designs that ensure that people using these areas can be easily 
seen (and can see out) should be encouraged. If a stair must be enclosed for code 
or weather protection purposes, glass walls can be used to deter potential attacks. 
Potential hiding places below stairs and within and around stairwells should be 
closed off.
_ Elevator cabs should have glass backs whenever possible. Elevator lobbies should be 
well-lighted and visible to both patrons in the parking areas and the people 
outside the building.
_ Pedestrian paths should be designed to concentrate activity to the extent possible. 
For example, bringing all pedestrians through one portal rather than allowing 
them to disperse to numerous access points improves the ability to see and be seen 
by other users. Limiting vehicular entry/exits to a minimum number of locations 
is also beneficial. 
2.8LOADING DOCKS AND SERVICE ACCESS
Loading docks and service access areas are commonly required for a building and are 
typically desired to be kept as invisible as possible. For this reason, special attention 
should be devoted to these service areas in order to avoid undesirable intruders. 
Design criteria for loading docks and service access include the following:
_ Separate (by at least 50 feet) loading docks and shipping and receiving areas in any 
direction from utility rooms, utility mains, and service entrances, including 
electrical, telephone/data, fire detection/alarm systems, fire suppression water 
mains, cooling and heating mains, etc.
_ Locate loading docks so that vehicles will not be allowed under the building. If this 
is not possible, the service should be hardened for blast. Loading dock design 
should limit damage to adjacent areas and vent explosive forces to the exterior of 
the building.
_ If loading zones or drive-through areas are necessary, monitor them and restrict 
height to keep out large vehicles.
_ Avoid having driveways within or under buildings.
_ Significant structural damage to the walls and ceiling of the loading dock may be 
acceptable; however, the areas adjacent to the loading dock should not experience 
severe structural damage or collapse. Provide adequate design to prevent extreme 
damage to loading docks. The floor of the loading dock does not need to be 
designed for blast resistance if the area below is not occupied and/or does not 
contain critical utilities.
_ Provide signage to clearly mark separate entrances for deliveries. 
2.9PHYSICAL SECURITY LIGHTING
Security lighting should be provided for overall site/building illumination and the 
perimeter to allow security personnel to maintain visual-assessment during darkness. 
It may provide both a real and psychological deterrent for continuous or periodic ob-
servation. Lighting is relatively inexpensive to maintain and may reduce the need for 
security personnel by reducing opportunities for concealment and surprise by 
potential attackers. Lighting is particularly desirable for sensitive areas of a site such 
as pier and dock areas, vital buildings, storage areas, and vulnerable control points in 
communications, power, and water distribution systems. It facilitates detection of 
unauthorized personnel and makes the job of an attacker more difficult.
At entry control points, a minimum surface lighting average of 4 horizontal foot-
candles will help ensure adequate lighting for pedestrians, islands, and guards. 
Where practical, high-mast lighting is recommended, because it gives a broader, 
more natural light distribution, requires fewer poles (less hazardous to the driver), 
and is more aesthetically pleasing than standard lighting. Lighting of the entry 
control point should give drivers a clear view of the gatehouse and, for security 
personnel, it gives a clear view of the drivers and vehicles. 
The type of site lighting system used depends on the overall requirements of the site 
and the building. Four types of lighting are used for security lighting systems:
_ Continuous lighting is the most common security-lighting system. It consists of a 
series of fixed lights arranged to flood a given area continuously during darkness 
with overlapping cones of light. Two primary methods of using continuous 
lighting are glare projection and controlled lighting:
  The glare projection security-lighting method lights the area surrounding a 
controlled area with high-intensity lighting. It is a strong deterrent to a 
potential intruder because it makes him or her very visible while making it 
difficult to see inside the secure area. Guards are protected by being kept in 
comparative darkness while being able to observe intruders at a considerable 
distance. This method should not be used when the glare of lights directed 
across the surrounding territory could annoy or interfere with adjacent 
operations.
  Controlled lighting is best when there are limits to the lighted area outside 
the perimeter, such as along highways. In controlled lighting, the width of 
the lighted strip is controlled and adjusted to fit the particular need. This 
method of lighting may illuminate or silhouette security personnel.
_ Standby lighting has a layout similar to continuous lighting; however, the lights are 
not continuously lit, but are either automatically or manually turned on when 
suspicious activity is detected or suspected by security personnel or alarm systems. 
_ Movable lighting consists of manually operated, movable searchlights that may be lit 
during hours of darkness or as needed. The system normally is used to supplement 
continuous or standby lighting.
_ Emergency lighting is a backup power system of lighting that may duplicate any or 
all of the above systems. Its use is limited to times of power failure or other 
emergencies that render the normal system inoperative. It depends on an 
alternative power source such as installed or portable generators or batteries. 
Consider emergency/backup power for security lighting as determined to be 
appropriate.
2.10SITE UTILITIES
Utility systems can suffer significant damage when subjected to the shock of an 
explosion. Some of these utilities may be critical for safely evacuating people from the 
building. Their destruction could cause damage that is disproportionate to other 
building damage resulting from an explosion. Additional information on 
mechanical systems is presented in Section 3.4. To minimize the possibility of such 
hazards, apply the following measures:
_ Where possible, provide underground, concealed, and protected utilities.
_ Provide redundant utility systems to support site security, life safety, and rescue 
functions.
_ Consider quick connects for portable utility backup systems if redundant sources 
are not available.
_ Prepare vulnerability assessments for all utility services to the site, including all 
utility lines, storm sewers, gas transmission lines, electricity transmission lines, 
and other utilities that may cross the site perimeter. 
_ Protect water treatment plants and storage tanks from waterborne contaminants by 
securing access points, such as manholes. Maintain routine water testing to help 
detect waterborne contaminants. 
_ Minimize signs identifying critical utility complexes (e.g., power plants and water 
treatment plants). Provide fencing to prevent unauthorized access and use 
landscape planting to conceal aboveground systems.
_ Locate petroleum, oil, and lubricant storage tanks and operations buildings 
downslope from all other buildings. Site fuel tanks at an elevation lower than 
operational buildings or utility plants. Locate fuel storage tanks at least 100 feet 
from buildings.
_ Locate the main fuel storage away from loading docks, entrances, and parking. 
Access should be restricted and protected (e.g., locks on caps and seals).
_ Provide utility systems with redundant or loop service, particularly in the case of 
electrical systems. Where more than one source or service is not currently 
available, provisions should be made for future connections. In the interim, 
consider "quick connects" at the building for portable backup systems.
_ Decentralize a sites communications resources when possible; the use of multiple 
communications networks will strengthen the communications systems ability to 
withstand the effects of a terrorist attack. Careful consideration should be made in 
locating, concealing, and protecting key network resources such as network 
control centers.
_ Place trash receptacles as far away from the building as possible; trash receptacles 
should not be placed within 30 feet of a building.
_ Conceal incoming utility systems within building and property lines, and give them 
blast protection, including burial or proper encasement, wherever possible.
_ Consider incorporating low impact development practices to enhance security, 
such as retaining stormwater on site in a pond to create stand-off, instead of 
sending into the sewer system.
_ Locate utility systems at least 50 feet from loading docks, front entrances, and 
parking areas.
_ Route critical or fragile utilities so that they are not on exterior walls or on walls 
shared with mailrooms.
_ Where redundant utilities are required in accordance with other requirements or 
criteria, ensure that the redundant utilities are not collocated or do not run in the 
same chases. This minimizes the possibility that both sets of utilities will be 
adversely affected by a single event.
_ Where emergency backup systems are required, ensure they are located away from 
the systems components for which they provide backup.
_ Mount all overhead utilities and other fixtures weighing 31 pounds (14 kilograms) 
or more to minimize the likelihood that they will fall and injure building 
occupants. Design all equipment mountings to resist forces of 0.5 times the 
equipment weight in any direction and 1.5 times the equipment weight in the 
downward direction. This standard does not preclude the need to design 
equipment mountings for forces required by other criteria such as seismic 
standards.
_ To limit opportunities for aggressors placing explosives underneath buildings, 
ensure that access to crawl spaces, utility tunnels, and other means of under 
building access is controlled.
All utility penetrations of a sites perimeter barrier, including penetrations in fences, 
walls, or other perimeter structures, should be sealed or secured to eliminate 
openings large enough to pass through the barrier. Typical penetrations could be for 
storm sewers, water, electricity, or other site utility services. Specific requirements of 
various openings are discussed below:
_ All utility penetrations of the sites perimeter should be screened, sealed, or secured 
to prevent their use as access points for unauthorized entry into the site. If access 
is required for maintenance of utilities, secure all penetrations with screening, 
grating, latticework, or other similar devices so that openings do not allow 
intruder access. Provide intrusion detection sensors and consider overt or covert 
visual surveillance systems if warranted by the sensitivity of assets requiring 
protection.
_ Drainage ditches, culverts, vents, ducts, and other openings that pass through a 
perimeter and that have a cross-sectional area greater than 96 square inches and 
whose smallest dimension is greater than 6 inches should be protected by securely 
fastened welded bar grilles. As an alternative, drainage structures may be 
constructed of multiple pipes, with each pipe having a diameter of 10 inches or 
less. Multiple pipes of this diameter may also be placed and secured in the inflow 
end of a drainage culvert to prevent intrusion into the area. Ensure that any 
addition of grills or pipes to culverts or other drainage structures is coordinated 
with the engineers so that they can compensate for the diminished flow capacity 
and additional maintenance that will result from the installation.
_ Manhole covers 10 inches or more in diameter must be secured to prevent 
unauthorized opening. They may be secured with locks and hasps, by welding 
them shut, or by bolting them to their frame. Ensure that hasps, locks, and bolts 
are made of materials that resist corrosion. Keyed bolts (which make removal by 
unauthorized personnel more difficult) are also available. If very high security is 
required, manhole covers that resist shattering after being artificially "frozen" by 
an aggressor should be considered.
2.11SUMMARY OF SITE MITIGATION   MEASURES
A general spectrum of site mitigation measures ranging from the least protection, 
cost, and effort going to the greatest protection, cost, and effort is presented below. 
Detailed discussions of individual measures can be found earlier in the chapter. This 
is a nominal ranking of mitigation measures. In practice, the effectiveness and cost 
of individual mitigation measures may be different for specific applications. Figure 2-
16 is a graphic summary of site mitigation measures to protect building occupants. 
Table 2-1 correlates mitigation measures to specific threats.
   Place trash receptacles as far away from the building as possible.
   Remove any dense vegetation that may screen covert activity.
   Use thorn-bearing plant materials to create natural barriers. 
   Identify all critical resources in the area (fire and police stations, hospitals, etc.).
   Identify all potentially hazardous facilities in the area (nuclear plants, chemical labs, etc.). 
   Use temporary passive barriers to eliminate straight-line vehicular access to high-risk buildings.
   Use vehicles as temporary physical barriers during elevated threat conditions.
   Make proper use of signs for traffic control, building entry control, etc. Minimize signs identifying high-
risk areas. 
   Identify, secure, and control access to all utility services to the building. 
   Limit and control access to all crawl spaces, utility tunnels, and other means of under building access to 
prevent the planting of explosives.
   Utilize Geographic Information Systems (GIS) to assess adjacent land use.
   Provide open space inside the fence along the perimeter.
   Locate fuel storage tanks at least 100 feet from all buildings. 
   Block sight lines through building orientation, landscaping, screening, and landforms.
   Use temporary and procedural measures to restrict parking and increase stand-off. 
   Locate and consolidate high-risk land uses in the interior of the site. 
   Select and design barriers based on threat levels. 
   Maintain as much stand-off distance as possible from potential vehicle bombs. 
   Separate redundant utility systems. 
   Conduct periodic water testing to detect waterborne contaminants. 
   Enclose the perimeter of the site. Create a single controlled entrance for vehicles (entry control point). 
   Establish law enforcement or security force presence.
   Install quick connects for portable utility backup systems.
   Install security lighting. 
   Install closed circuit television cameras.
   Mount all equipment to resist forces in any direction. 
   Include security and protection measures in the calculation of land area requirements.
   Design and construct parking to provide adequate stand-off for vehicle bombs.
   Position buildings to permit occupants and security personnel to monitor the site.
   Do not site the building adjacent to potential threats or hazards.
   Locate critical building components away from the main entrance, vehicle circulation, parking, or 
maintenance area. Harden as appropriate.
   Provide a site-wide public address system and emergency call boxes at readily identified locations.
   Prohibit parking beneath or within a building. 
   Design and construct access points at an angle to oncoming streets.
   Designate entry points for commercial and delivery vehicles away from high-risk areas.
   In urban areas, push the perimeter out to the edge of the sidewalk by means of bollards, planters, and other 
obstacles. For better stand-off, push the line farther outward by restricting or eliminating parking along the 
curb, eliminating loading zones, or through street closings.
    Provide intrusion detection sensors for all utility services to the building.
   Provide redundant utility systems to support security, life safety, and rescue functions.
   Conceal and/or harden incoming utility systems. 
   Install active vehicle crash barriers. 
2.12CRIME PREVENTION THROUGH  ENVIRONMENTAL DESIGN 
(CPTED)
CPTED is a crime reduction technique that has several key elements applicable to the 
analysis of building function and site design against physical attack. It is used by 
architects, city planners, landscape and interior designers, and law enforcement with 
the objective of creating a climate of safety in a community by designing a physical 
environment that positively influences human behavior. Although CPTED principles 
are not incorporated into the assessment process presented herein, it is useful to 
briefly discuss CPTED because it is often entwined with terrorism protection 
measures. Indeed, many antiterrorist design approaches are similar to those found in 
CPTED.
CPTED concepts have been successfully applied in a wide variety of applications, 
including streets, parks, museums, government buildings, houses, and commercial 
complexes. The approach is particularly applicable to older buildings that were 
designed and constructed 30 to 60 or more years ago. Security issues were almost 
nonexistent at the time, and technology was dramatically different. As a result, 
building designs are not always compatible with todays more security-conscious 
environment. 
According to CPTED principles, depending upon purely conventional physical 
security measures (e.g., security guards and metal detectors) to correct objectionable 
behavior may have its limitations. Although employing these measures will no doubt 
increase the level of physical security, in some cases physical security measures 
employed as standalone actions may lead to a more negative environment, thereby 
enhancing violence. In short, employing standalone physical security measures may 
fail to address the underlying behavioral patterns that adversely affect the particular 
environment. CPTED analysis focuses on creating changes to the physical and social 
environment that will reinforce positive behavior. 
CPTED builds on three strategies: 
_ Territoriality (using buildings, fences, pavement, signs, and landscaping to express 
ownership)
_ Natural surveillance (placing physical features, activities, and people to maximize 
visibility)
_ Access control (the judicial placement of entrances, exits, fencing, landscaping, 
and lighting)
A CPTED analysis of a building evaluates crime rates and stability, as well as core 
design shortcomings of the physical environment (e.g., blind hallways, uncontrolled 
entries, or abandoned areas that attract problem behavior). The application of 
CPTED principles starts with a threat and vulnerability analysis to determine the 
potential for attack and what needs to be protected. Protecting a building from 
physical attack by criminal behavior or terrorist activity, in many cases, only reflects a 
change in the level and types of threats. The CPTED process asks questions about 
territoriality, natural surveillance, and access control that can: 
_ Increase the effort to commit crime or terrorism
_ Increase the risks associated with crime or terrorism
_ Reduce the rewards associated with crime or terrorism
_ Remove the excuses as to why people do not comply with the rules and behave 
inappropriately 
The CPTED process provides direction to solve the challenges of crime and terrorism 
with organizational (people), mechanical (technology and hardware), and natural 
design (architecture and circulation flow) methods. 
CPTED concepts can be integrated into expansion or reconstruction plans for 
existing buildings as  well as new buildings. Applying CPTED concepts from the 
beginning usually has minimal impact on costs, and the result is a safer building. 
Each building, facility, and community should institute measures appropriate for 
their own circumstances because there is no single solution that will fit all situations. 
Many CPTED crime prevention techniques for a building complement conventional 
terrorism and physical attack prevention measures. For example, as part of the 
CPTED strategy of improving territoriality, buildings are encouraged to direct all 
visitors through one entrance that offers contact with a receptionist who can 
determine the purpose of the visit and the destination, and provide sign-in/sign-out 
sheets and an identification tag prior to building access. These CPTED measures are 
similar to and complement physical security entry control point stations.
However, in some cases, CPTED techniques can conflict with basic physical security 
principles. The CPTED strategy of natural surveillance calls for locating parking in 
areas that allow ease of monitoring. A design that locates parking close to a building 
or office also reduces vehicle stand-off and could create a vulnerability of the building 
structure to a vehicle bomb. In cases where CPTED techniques conflict with security 
principles, designers should seek innovative solutions tailored to the unique 
situation.







Figure 2-1 An example of using GIS to identify adjacent hazards. Note the large fuel storage and 
distribution facility (tank farm) in the vicinity of the office building being assessed


SOURCE: U.S. AIR FORCE, INSTALLATION FORCE PROTECTION GUID


Figure 2-2Clustered versus dispersed site layouts


SOURCE: U.S. AIR FORCE, INSTALLATION FORCE PROTECTION GUID


Figure 2-3 Clustering to enhance surveillance opportunities while minimizing views into the building


1U.S. EPA, Smart Growth Policy Database. http://cfpub.epa.gov/sgpdb/sgdb.cf


SOURCE: NATIONAL CAPITAL URBAN DESIGN AND SECURITY PLAN, NATIONAL CAPITAL PLANNING COMMISSION, 200


Figure 2-4 Streetscape security elements


SOURCE: NATIONAL CAPITAL URBAN DESIGN AND SECURITY PLAN, NATIONAL CAPITAL PLANNING COMMISSION, 200


Figure 2-4 Streetscape security elements (continued)


SOURCE: U.S. AIR FORCE, INSTALLATION FORCE PROTECTION GUID


Figure 2-5 Blocking of sight line


SOURCE: U.S. AIR FORCE, INSTALLATION FORCE PROTECTION GUID


Figure 2-6 Improper building siting and view relationship


Figure 2-7 Clear zone with unobstructed view


SOURCE: U.S. AIR FORCE, INSTALLATION FORCE PROTECTION GUID


Figure 2-8 Concept of stand-off distanc


SOURCE: U.S. AIR FORCE, INSTALLATION FORCE PROTECTION GUID


SOURCE: DEPARTMENT OF DEFENSE UNIFIED FACILITIES CRITERI


Figure 2-9 Stand-off distance and building separatio


SOURCE: U.S. AIR FORCE, INSTALLATION FORCE PROTECTION GUID


Figure 2-10 Exclusive and non-exclusive zone


SOURCE: U.S. AIR FORCE, INSTALLATION FORCE PROTECTION GUID


Figure 2-11 Application of perimeter barrier element


Figure 2-12 Using street closing to create a controlled access area


SOURCE: U.S. AIR FORCE, INSTALLATION FORCE PROTECTION GUID


Figure 2-13 Sample bollard application


Barrier Design Considerations
The effectiveness of a barrier is based on the amount of energy it can absorb versus the amount of 
kinetic energy, KE, imparted by a head-on vehicle impact:    
where M is the mass of the vehicle and v is the velocity at the time of impact with the barrier. The 
angle of approach reduces this energy in non-head-on situations and the energy absorbed by the 
crushing of the bumper also reduces the energy imparted to the barriers. Because the velocity is 
squared in this equation, a change in velocity affects the result more than a change in vehicle weight. 
For this reason, it is important to review lines of approach to ensure that a vehicle does not have a 
long, straight road to pick up speed before impact.  
The vehicle weight used for the design of barriers typically ranges from 4,000 pounds for cars up to 
40,000 pounds for trucks. Impact velocities typically range from 30 mph for slanted impact areas (i.e., 
where the oncoming street is parallel to the curb) up to 50 mph where there is straight-on access (i.e., 
where the oncoming street is perpendicular to the curb)


Figure 2-14 Examples of active and passive vehicle barrier


SOURCE: U.S. AIR FORCE, INSTALLATION ENTRY CONTROL FACILITIES DESIGN GUID


Figure 2-15 Combined multi-user gat


SOURCE: U.S. AIR FORCE, INSTALLATION FORCE PROTECTION GUID



1.   Locate assets stored on site, but outside the 
building within view of occupied rooms in the 
facility.
8.   Minimize vehicle access points.
2.   Eliminate parking beneath buildings.
9.   Eliminate potential hiding places near the 
building; provide an unobstructed view around 
building.
3.   Minimize exterior signage or other 
indications of asset locations.
10. Site building within view of other occupied 
buildings on the site.
4.   Locate trash receptacles as far from the 
building as possible.
11. Maximize distance from the building to the 
site boundary.
5.   Eliminate lines of approach perpendicular to 
the building.
12. Locate building away from natural or 
manmade vantage points.
6.   Locate parking to obtain stand-off distance 
from the building.
13. Secure access to power/heat plants, gas 
mains, water supplies, and electrical service.
7.   Illuminate building exteriors or sites where 
exposed assets are located.



Figure 2-16 Summary of site mitigation measure


Table 2-1: Correlation of Mitigation Measures to Threats




_   The 
symbo
ls 
indicat
e 
which 
of the 
protect
ive 
measu
res 
shown 
in the 
left-
hand 
colum
n can 
be 
effecti
ve in 
counte
ring 
the 
types 
of 
threats 
indicat
ed 
across 
the top 
of the 
chart.
Movin
g 
Vehicl
e 
Bomb
Stationar
y Vehicle 
Bomb
Exterio
r 
Attack
Stand-off 
Weapon
s Attack
Arme
d  
Attack
Cover
t 
Entry
Mail 
and 
Supplie
s 
Bombs
Airborne 
Contaminatio
n
Waterborne 
Contaminatio
n




LAND USE CONSIDERATIONS
Locate high-risk land uses in the interior of the 
site
_
_
_
_
_




Consolidate high-risk land uses
_
_
_
_
_




Include stand-off areas in land area 
requirements
_
_

_
_




Consider effects of off-property development
_
_
_

_





SITE PLANNING
Maximize distance from perimeter fence and developed 
areas
_
_
_
_
_


_

Site critical facilities on higher ground
_
_
_
_
_


_
_
Avoid areas with adjacent high terrain or structures


_
_
_


_
_
Avoid areas with adjacent dense vegetation


_
_
_




Avoiding low-lying topographic areas


_
_
_


_
_
Provide separation between facilities
_
_
_
_
_

_


Site facilities within view of other occupied facilities





_



Cluster facilities with similar threat levels
_
_

_
_




Create complexes to enhance surveillance opportunities
_
_
_
_
_




Eliminate vehicle parking from interior of building 
complexes
_
_







High surrounding terrain


_
_
_




Distance from non-building facilities
_
_
_
_
_
_

_
_
Areas that provide concealment

_
_
_
_
_



Earth berms

_
_
_
_




Bodies of water
_
_
_
_
_
_



Depressions


_
_
_




Protect against unwanted surveillance


_
_
_
_



"Defensible space"

_
_


_



Vehicle access
_
_







Dense thorn-bearing vegetation


_


_



Vegetation screens

_
_
_
_
_



Location of trash receptacles






_



STAND-OFF  DISTANCE 
Stand-off 
zone
_
_

_
_
_




CONTROLLED ACCESS ZONES
Exclusive zone/Non-exclusive 
zone
_
_



_



Clear zone
_
_



_



Fencing and physical barriers
_
_
_
_
_
_



Active barriers
_
_
_
_
_
_



Passive barriers
_
_
_


_




ENTRY CONTROL AND VEHICULAR ACCESS
Minimize access roads
_
_



_
_


Control points
_
_
_
_
_
_



Active monitoring
_
_
_
_
_
_
_
_
_
Provide enhanced protection at property entrances
_
_
_
_
_
_



Include pull-over lanes at checkpoints to inspect 
vehicles
_
_
_
_
_
_



Avoid straight-line vehicular access to high-risk 
resources
_
_







Avoid straight-line entry approach roads
_
_







Locate vehicle parking areas far from high-risk 
resources
_
_







Provide separate service and delivery access
_
_







Route major corridors away from high-risk resources
_
_

_
_




Locate high-risk resources remote from primary roads
_
_

_
_




Minimize directional identification signs 
_
_
_
_
_
_



Limit vehicular access to high-risk resources
_
_
_
_
_
_




SIGNAGE
Minimize 
signage
_
_
_
_
_
_
_
_
_

PARKING
View of parking

_







Parking under a building

_







Parking at interior of 
facility

_







Parking near high-risk 
areas

_







Parking in exclusive zone

_







One-way circulation
_
_
_


_




LOADING DOCKS AND SERVICE ACCESS
Loading/unloading docks

_




_


Driveways under 
facilities
_
_








PHYSICAL SECURITY 
LIGHTING 
Lighting

_
_


_





SITE UTILITIES
Provide protection at culverts, sewers, and pipelines




_
_


_
Provide protection at concrete trenches, storm drains, and duct 
systems




_
_


_
Provide and check locks on manhole covers




_
_


_
Minimize signs identifying utility systems 




_
_


_
Provide fencing at critical utility complexes





_


_
Use landscape planting to conceal aboveground systems





_


_
Install utilities underground
_
_
_
_
_
_
_


Locate fuel/lube storage downslope and away from facilities
_
_
_
_
_
_
_


Provide redundant utility systems and loop service
_
_
_
_
_
_
_


Provide utility "quick disconnects" for portable backup systems
_
_
_
_
_
_
_


Decentralize communications resources
_
_
_
_
_
_
_


Use multiple communications networks
_
_
_
_
_
_
_


Conceal and protect network control centers
_
_
_
_
_
_
_


Public address system


_

_


_
_
Underground utilities
_
_
_
_




_
Redundant utilities
_
_
_
_
_



_
Quick disconnects
_
_
_
_
_




Remote fuel storage
_
_
_
_
_









BUILDING DESIGN GUIDANCE     

This chapter addresses explosive blast and CBR concerns from terrorist attacks, 
highlighting mitigation measures that may be applied to building elements, 
including architectural, structural, and building envelope systems. After the site 
design considerations to enhance protection presented in Chapter 2 have been taken 
into account (recognizing that many may not be applicable to buildings in urban 
settings), additional building design measures, such as hardening, must be 
considered to protect building occupants. That is, when the desired level of 
protection cannot be achieved through site design, building envelope design 
measures must be considered. Catastrophic collapse of the building is a primary 
concern. Historically, the majority of fatalities that occur in terrorist attacks directed 
against buildings are due to building collapse. This was true for the Oklahoma City 
bombing in 1995 when 87 percent of the building occupants who were killed were in 
the collapsed portion of the Murrah Federal Building; however, other threats such as 
CBR agents should also be considered. 
When considering mitigation measures for explosive blast threats, the primary 
strategy is to keep explosive devices as far away from the building as possible 
(maximize stand-off distance). This is usually the easiest and least costly way to 
achieve a desired level of protection. In cases where sufficient stand-off distance is not 
available to protect the building, hardening of the buildings structural systems may 
be required, as well as design to prevent progressive collapse. In addition, designers 
should try to minimize hazardous flying debris during an explosive event because a 
high number of injuries can result from flying glass fragments and debris from walls, 
ceilings, and non-structural features. The hardening of the building envelope should 
be balanced so that the columns, walls, and windows have approximately equal 
response for damage and injury/casualty for the design basis threat weapon at the 
available stand-off distance. Window design is the element that is usually the most 
diverse in conventional construction. Good blast engineering is a multi-disciplinary 
effort that requires the concerted efforts of the architect, structural engineer, 
mechanical engineer, and the other design team members in order to achieve a bal-
anced building envelope.
When considering mitigation measures for CBR hazards, the HVAC systems are of 
particular concern. A building can provide protection against CBR agents released 
outdoors if the flow of fresh air is filtered or interrupted; however, HVAC systems can 
also become an entry point and distribution system for hazardous contaminants. If 
installed, HVAC air filtration and air-cleaning systems can reduce the effects of a CBR 
agent by removing the contaminants from the air within a building. There are a 
variety of ways to protect building occupants from airborne hazards. These protective 
measures can be as simple as defining a protective action plan or as complex as strict 
design measures practical only for new construction.
Building design should be optimized to facilitate emergency evacuation, rescue, and 
recovery efforts through effective placement, structural design, and redundancy of 
emergency exits and critical mechanical/electrical systems. Through effective 
structural design, the overall damage levels may be reduced to make it easier for 
people to get out safely and allow emergency responders to enter safely. The designer 
must also balance measures to protect people with the requirements of the ADAAG, 
UFAS, NFPC, and all applicable local building codes. 
 The primary focus of this chapter is the protection of buildings where the occupants 
are the primary asset. In this case, the objective of the designer is to save lives by 
mitigating building damages and reducing the chances of catastrophic collapse of 
the building, at least until the building is fully evacuated. The measures described in 
this chapter are designed to minimize the loss of life through deterrence and 
detection, as well as strengthening of the building against a variety of terrorist tactics. 
The design team must determine which measures are appropriate and cost-effective 
for incorporation into the building design. The measures presented here are not all-
inclusive, and additional technical information for implementation can be found in 
the referenced documents.
3.1 ARCHITECTURAL
A lot can be done architecturally to mitigate the effects of a terrorist bombing on a 
facility. These measures often cost nothing or very little if implemented early in the 
design process. Architectural considerations include building configuration, space 
design, and building detailing. It is recommended that architects be brought into the 
design process as early as site selection, to optimize the protection provided. FEMA 
430 contains an expanded discussion of incorporating security components in 
architectural design.
3.1.1 Building Configuration
The vertical or horizontal profile of a building has implications for its protection. As 
with the discussion of clustered versus dispersed buildings, designers should balance 
a number of relevant considerations to the extent that site, economic, and other 
factors allow. Some of the relevant considerations include the following:
Low, Large-footprint Buildings:
_  Distribute people, assets, and operations across a wider area, to limit damage 
_  Use vegetation, terrain, and other screening elements to protect from hostile 
surveillance 
_  Maximize the benefits of green roof technologies, which can help reduce a 
buildings heat signature and lower its visual profile
_  Require the use of  additional measures (at additional cost) to prevent introduction 
of CBR agents due to easier access to HVAC intakes by intruders
Tall, Small-footprint Buildings:
_  Suffer damage to a greater percentage of their faades, structures, and interiors at 
best, and catastrophic damage or collapse at worst, should a large blast occur near 
the building if not constructed with progressive collapse prevention in mind
_  Elevate occupied areas above vegetation, terrain, and other screening elements, 
making it potentially more difficult to protect interior spaces from outside 
surveillance
_  Minimize the amount of impervious surface, contributing to a reduction in 
stormwater runoff, which reduces the need for culverts, drainage pipes, manholes, 
and other covert site access and weapon concealment opportunities
_  Provide greater opportunity to elevate HVAC intakes to prevent the introduction of 
CBR agents
The shape of the building may also contribute to the overall damage to the structure. 
For example, "U" or "L" shaped buildings tend to trap shock waves, which may 
exacerbate the effect of explosive blasts. For this reason, it is recommended that re-
entrant corners be avoided. In general, convex rather than concave shapes are 
preferred for the exterior of the building. For example, circular buildings act to 
reduce the air-blast pressures because the angle of incidence of the shock wave 
increases more rapidly than in a rectangular building. The following design 
considerations are recommended:
_  Reduce a buildings vulnerability to attack by using earth-sheltered design 
_  Orient buildings horizontally rather than vertically to reduce the buildings profile 
and exposure
_  Place the ground floor elevation of a building at 4 feet above grade to prevent 
vehicle ramming
_  Avoid eaves and overhangs, because they can be points of high local pressure and 
suction during blasts; when these elements are used, they should be designed to 
withstand blast effects
_  Orient glazing perpendicular to the primary facade to reduce exposure to blast and 
projectiles (see Figure 3-1)
_  Avoid exposed structural elements (e.g., columns) on the exterior of the facility
_  Provide pitched roofs to allow deflection of launched explosives
_  Avoid re-entrant corners on the building exterior where blast pressures may build 
up (see Figure 3-2)
        
3.1.2Space Design
Unsecured areas should be physically separated from the main building to the extent 
possible. For example, a separate lobby pavilion or loading dock outside the main 
footprint provides enhanced protection against damages and potential building col-
lapse in the event of an explosion. Similarly, placing parking areas outside the main 
footprint of the building can be highly effective in reducing the vulnerability to 
catastrophic collapse.
The protection of the building interior can be divided into two categories: functional 
layout and structural layout. In terms of functional layout, public areas such as the 
lobby, loading dock, mail room, garage, and retail areas need to be separated from 
the more secured areas of the facility. This can be done by creating internal "hard 
lines" or buffer zones, using secondary stairwells, elevator shafts, corridors, and 
storage areas between public and secured areas.
In lobby areas, the architect would be wise to consider the queuing requirements in 
front of the inspection stations so that visitors are not forced to stand outside during 
bad weather conditions or in a congested line inside a small lobby while waiting to 
enter the secured areas.
Emergency functions (e.g., sprinkler systems and generators, which are critical for 
mitigating the effects of an explosion) and elevator shafts should be placed away from 
internal parking areas and loading docks. In the 1993 World Trade Center bombing 
incident, elevator shafts became chimneys, transmitting smoke and heat from the 
explosion in the basement to all levels of the building. This hindered evacuation and 
caused smoke inhalation injuries. When it is not possible to separate mechanical 
areas and parking, the walls need to be designed to resist explosive forces. The 
following design measures should be considered:
_  Do not collocate high-risk facilities with lower risk tenants. For example, a post 
office or supply center/room should not be located in the same building as a 
childcare facility.
_  Locate key assets as far into the interior of a building as possible.
_  Place areas of high visitor activity away from key assets.
_  Locate critical assets in spaces that are occupied 24 hours per day.
_  Locate assets in areas where they are visible to more than one person.
_  Eliminate hiding places within the building.
_  Use interior barriers to differentiate levels of security within a building.
_  Stagger doors located across from one another in interior hallways to limit the 
effects of a blast through a structure (see Figure 3-3).
_  Provide foyers with reinforced concrete walls, and offset interior and exterior doors.
_  Consider methods to facilitate the venting of explosive forces and gases from the 
interior spaces to the outside of the structure. Examples of such methods include 
the use of blow-out panels and window system designs that provide protection 
from blast pressure applied to the outside, but that readily fail and vent if exposed 
to blast pressure on the inside.
_ Physically isolate lobbies, mailrooms (includes various mail processing areas), 
loading docks, and other entry and storage areas from the rest of the building. 
These are areas where bulk quantities of CBR agents are likely to enter a building. 
Building doors, including vestibule and loading dock doors, should remain 
closed when not in use.
_ Design buildings so that lobbies, mailrooms, and loading docks do not share a 
return-air system or return pathway (e.g., ceiling plenum) with other areas of the 
building. Some of these measures are more feasible for new construction or 
buildings undergoing major renovation. 
3.1.3 Other Design Considerations
When designing high-risk buildings, engineers and architects should consider the 
following:
_  Safe havens. The innermost layer of protection within a physical security system is 
the safe haven. Safe havens are not intended to withstand a disciplined, 
paramilitary attack featuring explosives and heavy weapons. The safe haven should 
be designed such that the time attackers need to penetrate the protected area is 
greater than the time that first responders need to reach the protected area. For 
additional information on safe havens, see FEMA 428, Primer to Design Safe School 
Projects in Case of Terrorist Attacks.
_  Office locations. Offices considered to be high risk (more likely to be targeted by 
terrorists) should be placed or glazed so that the occupants cannot be seen from 
an uncontrolled public area such as a street. Whenever possible, these spaces 
should face courtyards, internal sites, or controlled areas. If this is not possible, 
suitable obscuring glazing or window treatment should be provided, including 
ballistic-resistant glass, blast curtains, or other interior protection systems.
_  Mixed occupancies. High-risk tenants should not be housed with low-risk tenants. 
Terrorists may identify some targets based on their symbology, visibility, ideology, 
political views, potential for publicity, or simply the consequences of their loss. 
_  Public toilets and service areas. Public toilets, service spaces, or access to vertical 
circulation systems should not be located in any non-secure areas, including the 
queuing area before visitor screening at the public entrance.
_  Retail uses in the lobby. Retail and other mixed uses, which have been encouraged 
in public buildings by the Public Buildings Cooperative Use Act of 1976, create 
spaces that are open and inviting. Although important to the public nature of the 
buildings, the presence of retail and other mixed uses may present a risk to 
buildings and their occupants and should be carefully considered on a project-
specific basis during project design. In areas exposed to potential terrorist attacks, 
retail and mixed uses may be accommodated through such means as separating 
entryways, controlling access, and hardening shared partitions, as well as with 
special security operational countermeasures.
_  Stairwells. Stairwells required for emergency egress should be located as remotely as 
possible from areas where blast events might occur and, wherever possible, should 
not discharge into lobbies, parking, or loading areas. 
_  Mailroom. The mailroom should be located away from facility main entrances areas 
containing critical services, utilities, distribution systems, and important assets. In 
addition, the mailroom should be located at the perimeter of the building with an 
outside wall or window designed for pressure relief. It should have adequate space 
for explosive disposal containers. An area near the loading dock is a preferred 
mailroom location. Where these rooms are located in occupied areas or adjacent 
to critical utilities, walls, ceilings, and floors, they should be blast- and fragment-
resistant. Significant structural damage to the walls, ceilings, and floors of the 
mailroom is acceptable; however, the areas adjacent to the mailroom should not 
experience severe damage or collapse.
_  Non-structural elements. False ceilings, light fixtures, venetian blinds, ductwork, air 
conditioners, and other equipment may become flying debris in the event of an 
explosion. Wherever possible, it is recommended that the design be simplified to 
limit these hazards. Placing heavy equipment such as air conditioners near the 
floor rather than the ceiling is one idea; using curtains rather than venetian 
blinds, and using exposed ductwork as an architectural device are others.
3.2 BUILDING STRUCTURAL AND NON-STRUCTURAL SYSTEMS
3.2.1 Building Design to Achieve a Desired Protection Level
The assessment process described in Chapter 1 determines the level of protection 
sought for the building structure and defines the threat/hazard specific to the 
facility. Explosive blast threats usually govern building structural design for high-risk 
buildings. A structural engineer should determine the building design features 
needed to achieve the desired level of protection against the design blast threat, 
considering collapse of the building, as well as incipient injuries and fatalities. In 
addition, Chapter 4 discusses other structural systems related to explosive blast.
3.2.2 Progressive Collapse
Progressive collapse is a situation where local failure of a primary structural 
component leads to the collapse of adjoining members, which, in turn, leads to 
additional collapse. Hence, the total damage is disproportionate to the original 
cause. Progressive collapse is a chain reaction of structural failures that follows from 
damage to a relatively small portion of a structure. Information on progressive 
collapse can also be found in FEMA 427, Primer for Design of Commercial Buildings to 
Mitigate Terrorist Attacks.
All buildings should be designed with the intent of reducing the potential for 
progressive collapse as a result of an abnormal loading event, regardless of the 
required level of protection. The following structural characteristics (from GSA 
Progressive Collapse Analysis and Design Guidelines for New Federal Office Buildings and Major 
Modernization Projects, November 2000) should be considered in the initial phases of 
structural design. Incorporation of these features will provide a more robust structure 
and decrease the potential for progressive collapse. Designers should consider the 
following:
_  Redundancy. The use of redundant lateral and vertical force resisting systems is 
highly encouraged when considering progressive collapse. Redundancy tends to 
promote a more robust structure and helps to ensure that alternate load paths are 
available in the case of a structural element(s) failure. Additionally, redundancy 
provides multiple locations for yielding to occur, which increases the probability 
that damage will be constrained.
_  The use of ductile structural elements and detailing. It is critical that both the 
primary and secondary structural elements be capable of deforming well beyond 
the elastic limit, without experiencing structural collapse. The use of ductile 
construction materials (i.e., steel, cast-in-place reinforced concrete, etc.) for both 
the structural elements and connection detailing is encouraged. The capability of 
achieving a ductile response is imperative when considering an extreme 
redistribution of loading such as that encountered in structural element(s) 
failure.
_  Capacity for resisting load reversals. Both the primary and secondary structural 
elements should be designed to resist load reversals in case of a structural 
element(s) failure.
_  Capacity for resisting shear failure. Primary structural elements maintain sufficient 
strength and ductility under an abnormal loading event to preclude a shear 
failure. If the shear capacity is reached before flexural capacity, the sudden, non-
ductile failure of the element could potentially lead to a progressive collapse of the 
structure.
Both the GSA and DoD take a threat-independent approach to progressive collapse. 
The goal of a threat-independent approach is not to prevent collapse from a specific 
design threat, but to control and stop the continuing spread of damage after 
localized damage or localized collapse has occurred.
The GSA and DoD require that the structural response of a building be analyzed in a 
test that removes a key structural element (e.g., vertical load carrying column, section 
of bearing wall, beam, etc.) to simulate local damage from an explosion. If effective 
alternative load paths are available for redistributing the loads, originally supported 
by the removed structural element, the building has a low potential for progressive 
collapse. The details of the GSA and DoD guidelines and criteria can be found in GSA 
Progressive Collapse Analysis and Design Guidelines for New Federal Office Buildings and Major 
Modernization Projects (November 2000) and DoD Unified Facilities Criteria (UFC) 4-010-01 
(31 July 2002). Although these criteria provide specific guidance on which structural 
elements must be analyzed for removal from the structural design configuration, they 
do not provide specific guidance for choosing an engineering structural response 
model for verifying the effectiveness of alternate load paths.  
Several other design codes and guidelines in use throughout the world (notably in 
the United Kingdom and Sweden) require some form of analysis or measures to 
reduce the potential for progressive collapse. However, there is no specific 
engineering design method prescribed for the structural design process to prevent 
progressive collapse. Unless a building is being designed to meet the GSA or DoD 
criteria, it is up to the owner and the design team to decide how much progressive 
collapse analysis and mitigation to incorporate into their design. 
To address blast resistance (Chapter 4 contains a detailed discussion of explosive 
blast theory) and to minimize the possibility of progressive collapse, the priority of 
upgrades should be based on the relative importance of a structural or non-structural 
element, in the order below:
_  Primary structural elements. These are the essential parts of the buildings 
resistance to catastrophic blast loads and progressive collapse (e.g., columns, 
girders, roof beams, and the main lateral resistance system).
_  Secondary structural elements. These include all other load bearing members (e.g., 
floor beams, slabs, etc.).
_  Primary non-structural elements. These are the elements (including their 
attachments) that are essential for life safety systems or elements that can cause 
substantial injury if failure occurs (e.g., ceilings or heavy suspended mechanical 
units).
_  Secondary non-structural elements. These include elements not covered in primary 
non-structural elements (e.g., partitions, furniture, and light fixtures).
Priority should be given to the critical elements that are essential to mitigating the 
extent of collapse. Designs for secondary structural elements should minimize injury 
and damage. Consideration should be given to reducing damage and injury from 
primary as well as secondary non-structural elements. For example, if an explosive 
event causes the local failure of one column, which results in major collapse within a 
structural bay, a design that mitigated progressive collapse would preclude the 
additional loss of primary structural members beyond this localized damage zone 
(i.e., the loss of additional columns, main girders, etc.). This would not necessarily 
preclude the additional loss of secondary structural or non-structural elements 
outside the initial zone of localized damage, provided the loss of such members is 
acceptable for that performance level and the loss does not precipitate the onset of 
progressive collapse.
3.2.3 Loads and Stresses
Structures should be designed to resist blast loads. The DoD designates the level of 
blast protection a building must meet based on how many occupants it contains and 
its function. The demands on the structure will be equal to the combined effects of 
dead, live, and blast loads. Blast loads or dynamic rebound may occur in directions 
opposed to typical gravity loads.
For purposes of designing against progressive collapse, loads should be defined as 
dead load plus a realistic estimate of actual live load. The value of the live load may be 
as low as 25 percent of the code-prescribed live load. The design should use ultimate 
strengths with dynamic enhancements based on strain rates. Allowable responses are 
generally post elastic.
3.2.4 Good Engineering Practice Guidelines
The following guidelines are commonly used to mitigate the effects of blast on 
structures and to mitigate the potential for progessive collapse. Details and more 
complete guidance are available in the references below. These guidelines are not 
meant to be complete, but are provided to assist the designer in the initial evaluation 
and selection of design approaches. For higher levels of protection from blast, cast-
in-place reinforced concrete is normally the construction type of choice. Other types 
of construction such as properly designed and detailed steel structures are also 
allowed. Several material and construction types, although not disallowed by these 
criteria, may be undesirable and uneconomical for protection from blast. 
_  Consider incorporating internal damping into the 
structural system to absorb the blast impact. 
_  The use of symmetric reinforcement can increase the 
ultimate load capacity of the structure. 
_  Consider wire mesh in plaster to reduce the incidence 
of flying fragments.
_  Avoid the use of masonry when blast is a threat. 
Masonry walls break up readily and become secondary 
fragments during blasts. 
_  The use of multiple barrier materials and construction techniques can sometimes 
accomplish the same goal with less expense than a single material or technique.
_  The designer should recognize that components might act in directions for which 
they were not designed. This is due to the engulfment of structural members by 
blast, the negative phase, the upward loading of elements, and dynamic rebound 
of members. Making steel reinforcement (positive and negative faces) symmetric 
in all floor slabs, roof slabs, walls, beams, and girders will address this issue. 
Symmetric reinforcement also increases the ultimate load capacity of the 
members.
_  Lap splices should fully develop the capacity of the reinforcement.
_  Lap splices and other discontinuities should be staggered.
_  Deflections around certain members, such as windows, should be controlled to 
prevent premature failure. Additional reinforcement is generally required.
_  In general, column spacing should be minimized so that reasonably sized members 
can be designed to resist the design loads and increase the redundancy of the 
system. A practical upper level for column spacing is 30 feet for the levels of blast 
loads described herein.
_  In general, floor to floor heights should be minimized. Unless there is an 
overriding architectural requirement, a practical limit is generally less than or 
equal to 16 feet.
_  It is recommended that the designer use fully grouted and reinforced concrete 
masonry unit (CMU) construction when CMU is selected.
_  It is essential that the designer actively coordinate structural requirements for blast 
with other disciplines, including architectural and mechanical.
_  The use of one-way wall elements spanning from floor-to-floor is generally a 
preferred method to minimize blast loads imparted to columns.
_  In many cases, the ductile detailing requirements for seismic design and the 
alternate load paths provided by progressive collapse design assist in the 
protection from blast. The designer must bear in mind, however, that the design 
approaches are, at times, in conflict. These conflicts must be worked out on a case 
by case basis.
_  It is recommended that architectural or structural features be used that deny 
contact with exposed primary vertical load members. A minimum stand-off of at 
least 6 inches from these members is required.
3.2.5 Building Materials
All building materials and types acceptable under model building codes are allowed; 
however, special consideration should be given to materials that have inherent 
flexibility and that are better able to respond to load reversals (i.e., cast in place 
reinforced concrete and steel construction). Careful detailing is required for material 
such as pre-stressed concrete, pre-cast concrete, and masonry (brick and concrete 
masonry unit) to adequately respond to the design loads. The construction type 
selected must meet all performance criteria of the specified level of protection.
3.2.6    Methods and References
All building components requiring blast resistance should be designed using 
established methods and approaches for determining dynamic loads, structural 
detailing, and dynamic structural response. Design and analysis approaches should 
be consistent with those in the technical manuals or the GSA Security Design Criteria 
and the American Society of Civil Engineers Minimum Design Loads for Buildings and 
Other Structures, ASCE 7. Alternative analysis and mitigation methods are permitted, 
provided that the performance level is attained. A peer group should evaluate new and 
untested methods.
3.3 BUILDING ENVELOPE
3.3.1 Building Exterior
At the building exterior, the focus shifts from deterring and delaying the attack, to 
mitigating the effects of an explosion. The exterior envelope of the building is the 
most vulnerable to an exterior explosive threat because it is the part of the building 
closest to the weapon. 
It also is a critical line of defense for protecting the occupants of the building from 
CBR threats. Significant quantities of air can enter a building by means of infiltration 
through unintentional leakage paths in the building envelope. Such leakage is of 
more concern during an exterior CBR release, such as a large-scale attack, than for a 
directed terrorist act. The reduction of air leakage is a matter of tight building 
construction in combination with building pressurization. Although building 
pressurization may be a valuable CBR-protection strategy in any building, it is much 
more likely to be effective in a tight building. However, to be effective, filtration of 
building supply air must be appropriate for the CBR agent introduced. Although 
increasing the air tightness of an existing building can be more challenging than 
during new construction, it should still be seriously considered.
The design philosophy to be used here is that simpler is better. Generally, simple 
geometries, with minimal ornamentation (which may become flying debris during 
an explosion) are recommended. If ornamentation is used, it is recommended that it 
consist of lightweight material such as timber or plastic, which is less likely to 
become a projectile in the event of an explosion than, for example, brick, stone, or 
metal.
Soil can be highly effective in reducing the impact of a major explosive attack. 
Bermed walls and buried rooftops have been found to be highly effective for military 
applications and can be effectively extended to conventional construction. This type 
of solution can also be effective in improving the energy efficiency of the building. 
Note that, if this approach is taken, no parking should be permitted on top of the 
building. 
3.3.2 Exterior Wall Design
The exterior walls provide the first line of defense to prevent air-blast pressures and 
hazardous debris from entering the building. They would be subject to direct 
reflected pressures from an explosive threat located directly across from the wall 
along the secured perimeter line. If the building is more than four stories high, it 
may be advantageous to consider the reduction in pressure with height due to the 
increased distance and angle of incidence. At a minimum, the objective of design is 
to ensure that these members fail in a flexible mode rather than a brittle mode such 
as shear. The walls also need to be able to resist the loads transmitted by the windows 
and doors. It is not uncommon for bullet-resistant windows to have a higher ultimate 
capacity than the walls to which they are attached. Beyond ensuring a flexible failure 
mode, the exterior wall may be designed to resist the actual or reduced pressure levels 
of the defined threat. Special reinforcing and anchors should be provided around 
blast-resistant window and door frames. 
Poured-in-place reinforced concrete will provide the highest level of protection, but 
solutions like pre-cast concrete, reinforced CMU block, and metal studs may also be 
used to achieve lower levels of protection. 
For pre-cast panels, consider a minimum thickness of 5 inches with two-way 
reinforcing bars spaced not greater than the thickness of the panel. Connections 
into the structure should provide a straight line of load transmittal, using as few 
connecting pieces as possible.
For CMU block walls, use 8-inch block walls, fully grouted with vertical centered 
reinforcing bars placed in each cell and horizontal reinforcement at each layer. 
Connections into the structure should be able to resist the ultimate lateral capacity of 
the wall. A preferred system is to have a continuous exterior CMU wall that laterally 
bears against the floor system. For increased protection, consider using 12-inch 
blocks with two layers of reinforcement.
For metal stud systems, use metal studs back to back and mechanically attached, to 
minimize lateral torsion effects. To catch exterior cladding fragments, attach a wire 
mesh to the exterior side of the metal stud system. The supports of the wall are to be 
designed to resist the ultimate lateral capacity load of the system.
Exterior Walls. For the design of exterior walls, consider the following:
_  Exterior walls should resist the actual pressures and impulses acting on the exterior 
wall surfaces from the threats defined for the facility.
_  Exterior walls should be capable of withstanding the dynamic reactions from the 
windows.
_  Shear walls that are essential to the lateral and vertical load bearing system, and 
that also function as exterior walls, should be considered primary structures. 
Design exterior shear walls to resist the actual blast loads predicted from the 
threats specified.
_  Special consideration should be given to construction types that reduce the 
potential for collapse where exterior walls are not designed for the full design 
loads.
_  By U.S. military standards (per Army Technical Manual 5-853), a medium 
protection level for walls would be the equivalent of 4-inch concrete with #5 
reinforcing steel at 6-inch intervals each way or 8-inch CMU with #4 reinforcing 
steel at 8-inch intervals. TM 5-853 provides other alternatives for low, medium, and 
high protection.
Cladding and Finishes. Designers should consider the following:
_  Substitute strengthened building elements and systems when stand-off distances 
cannot be accommodated.
_  Use ductile materials capable of very large plastic deformations without complete 
failure.
_  Provide blast-resistant walls when a high threat is present.
_  Consider use of sacrificial exterior wall panels to absorb blast.
_  Use earthtone-colored materials and finishes on exterior surfaces to diminish the 
prominence of a building.
_  Consider reinforced concrete wall systems in lieu of masonry or curtain walls to 
minimize flying debris in a blast.
_  Reinforced wall panels can protect columns and assist in preventing progressive 
collapse, because the wall will assist in carrying the load of a damaged column.
Exterior Column Design. Exterior columns should be designed to resist the peak 
reflected pressure of an explosive event, including the load transmitted by supported 
walls. Because these elements are slender, the air-blast tends to "wash around" them if 
they are free standing, reducing the duration of the loading. This is referred to as a 
"clearing time" effect. Although it is conservative to neglect these effects, it may be 
advantageous to take them into account in some situations, like close-in explosions. 
The design must provide for both the axial and flexible loads and stability. For 
concrete columns, spiral reinforcing or closed stirrups should be placed at a spacing 
of not less than half the minimum thickness of the member to ensure that adequate 
confinement and ductility are provided. For steel columns, the connections are the 
most vulnerable part of the design. If possible, place the base plate below ground level 
and protect with concrete and use multi-story segments for the lower floors.
3.3.3 Window Design
Window systems on the exterior faade of a building should be designed to mitigate 
the hazardous effects of flying glass during an explosion event. Designs should 
integrate the features of the glass, connection of the glass to the frame (bite), and 
anchoring of the frame to the building structure to achieve a "balanced design."  
This means all the components should have compatible capacities and theoretically 
would all fail at the same pressure-pulse levels. In this way, the damage sequence and 
extent of damage are controlled. Table 3-1 presents six GSA glazing protection levels 
based on how far glass fragments would enter a space and potentially injure its 
occupants. Figure 3-4 depicts how far glass fragments could enter a structure for each 
GSA performance condition. 
The divide between performance conditions 3a and 3b can be equated to the 
"threshold of injury."  The divide between performance conditions 4 and 5 can be 
equated to the "threshold of lethality."  The GSA glazing performance conditions 
shown below correlate with the DoD levels of protection presented in Table 3-2.Glass 
Design. Four types of glass are commonly used in window glazing systems: annealed 
glass, heat strengthened glass, fully thermally tempered glass, and polycarbonate. 
Other types of glass materials exist, but are not commonly used in typical commercial 
window systems. Of the four common types, annealed glass and fully thermally 
tempered glass are the type of windows for most office buildings. 
Annealed glass, also known as float, plate, or sheet glass, is the most common glass 
type used in commercial construction. Annealed glass is of relatively low strength 
and upon failure, fractures into razor sharp, dagger-shaped fragments (see Figure 3-
5). 
Fully thermally tempered glass (TTG) is typically four to five times stronger than 
annealed glass with a design stress of 16,000 psi (112,000 kPa). The fracture 
characteristics of tempered glass are superior to those of annealed glass. Upon 
failure, it will eventually fracture into small cube-shaped fragments. Breakage 
patterns of side and rear windows in American automobiles are a good example of the 
failure mode of thermally tempered glass. Current building codes generally require 
thermally tempered glass anywhere the public can physically touch the glass such as 
entrance doors and sidelights. Although thermally tempered glass exhibits a 
relatively safe failure mode for conventional usage, failure under blast loading still 
presents a significant health hazard. Results from blast tests reveal that, upon 
fracture, TTG fragments may be propelled into cohesive clumps that only fragment 
upon impact into smaller rock salt-type fragments. Even if the tempered glass breaks 
up initially into small fragments, the blast overpressure can propel the fragments at a 
high enough velocity to constitute a severe hazard.
Wire-reinforced glass is a common glazing material. It consists of annealed glass with 
an embedded layer of wire mesh. Its primary use is as a fire-resistant and forced entry 
barrier. Wire-reinforced glass has the fracture and low strength characteristics of 
annealed glass and, although the wire binds some fragments, it still ejects a 
considerable amount of sharp glass and metal fragments. Wire-reinforced glass is not 
recommended for blast-resistant windows. 
Laminated glass is a pane with multiple glass layers and a pliable interlayer material 
(usually made from polyvinyl butyral (PVB)) between the glass layers. Combining 
interlayer bonding materials with layers of glass produces cross-sections that perform 
well against blast, ballistic, and forced entry attacks. The interlayer acts as the glue 
that bonds the multiple layers of glass into a single pane of a given thickness and 
provides a membrane response after the glass layers crack under loading. Laminated 
glass offers significant advantages over monolithic glass. It is stronger and, if failure 
occurs, the interlayer material may retain most of the glass fragments. Also, if a 
projectile passes through the glass, most spalling glass fragments will be retained. 
Increased safety for fragment retention can be obtained in the event of catastrophic 
failure from an explosive blast by placing a decorative crossbar or grillwork on the 
interior of the glazing. Note, crossbars must be mounted across the center of mass of 
each window pane to be effective. 
Another treatment used for mitigating the effects of an explosive attack is security 
window film. The polyester film used in commercial products is commonly referred 
to as fragment retention film (FRF), safety film, security film, protective film, or 
shatter-resistant film. These films are adhered to the interior surface of the window to 
provide fragment retention and reduce the overall velocity of the glass fragments at 
failure. Fragment retention film combines a strong pressure sensitive adhesive with a 
tough polyester layer. Four methods are used to attach security film to windows: a 
daylight attachment (applied only to the vision opening); edge-to-edge attachment 
(applied out to the edge of the glass); wet-glazed attachment (daylight or edge-to-edge 
film with a silicone bead along edge of the frame); and a mechanical attachment. 
Because fragment retention film applies directly to the glass surface of a window 
pane, it is beneficial for retrofitting existing windows as well as on new windows. 
Fragment retention film behaves similarly to relatively thin laminated and 
polycarbonate glazing in terms of fragmentation. It is available in common 
thicknesses of 2, 4, 7, and 10 mils. Fragment retention film improves the performance 
of the glass under blast loading to varying degrees, depending on the thickness, 
quality, and type of film installation. The best performance is achieved when the film 
is installed into the bite of the glazing or is connected to the frame. Fragment 
retention film can also provide solar control benefits. As with laminates, increased 
safety can be obtained with window films by placing a decorative crossbar or grillwork 
on the interior of the glazing.
Thermoplastic polycarbonates are very strong and suitable for blast- and forced entry-
resistant window design. Monolithic polycarbonate is available in thicknesses up to 
12 inch, but can be fused together to obtain any thickness needed. However, 
polycarbonate is expensive and subject to environmental degradation (especially 
from exposure to aromatic hydrocarbons) and abrasion. Local building codes should 
be consulted when considering polycarbonates. There are several fire safety issues 
associated with its use (thermoplastic polycarbonate is rated as a class CC-1 material 
and will often test with a smoke density rating over 500). Additionally, because of its 
strength, local fire codes may require a percentage of polycarbonate glazing to pop 
out for emergency egress.
Frame and Anchorage Design. Window frames need to retain the glass so that the 
entire pane does not fall out and also should be designed to resist the breaking stress 
of the window glass. To retain the glass in the frame, a minimum of a 14-inch bead of 
structural sealant (i.e., silicone or polyvinyl butyral) should be used around the inner 
perimeter of the window. The allowable tensile strength should be at least 20 psi. 
Also, the window bite (i.e., the depth of window captured by the frame) needs to be at 
least 12 inch. In some applications (e.g., the lobby area where large panes of glass are 
used), a larger bite with more structural sealant may be needed. Frame and anchorage 
design is performed by applying the breaking strength of the window to the frame 
and the fasteners. In most conventionally designed buildings, the frames will be 
aluminum; however, in some applications, steel frames are used. 
Mullion and Wall Design. The frame members connecting adjoining windows are 
referred to as mullions. These members may be designed using a static approach 
when the breaking strength of the window glass is applied to the mullion, or a 
dynamic load may be applied using the peak pressure and impulse values. Although 
the static approach may seem easier, it often yields a design that is not practical, 
because the mullion can become very deep and heavy, driving up the weight and cost 
of the window system. In addition, it may not be consistent with the overall 
architectural objectives of the project. A dynamic approach is likely to provide a 
section that meets the design constraints of the project. To accomplish this, a single-
degree-of-freedom solution is often used. The governing equation of motion may be 
solved using numerical methods. There are also charts available for linearly decaying 
loads that circumvent the need to solve differential equations. These charts only 
require that the fundamental period of the mullion (including the tributary area of 
the window glass), the ultimate resistance force of the mullion, the peak pressure, 
and the equivalent linear decay time are known.
Peak lateral response of the mullion is to be limited to a 2-degree support rotation. 
Also, the displacement ductility is to be limited to a 4-degree support rotation. As with 
frames, it is good engineering practice to limit the number of interlocking parts used 
for the mullion. 
A similar approach may be used for checking the response of the supporting wall 
response. It makes no sense to have blast mitigating windows if they are stronger 
than the wall that they are anchored into. The maximum strength of any window and 
anchorage system should be equal to the wall strength. This becomes particularly 
important in the design of ballistic-resistant and forced entry mitigating windows, 
which consist of one or more inches of glass and polycarbonate. These windows can 
easily become stronger than the supporting wall. In some applications, even the use 
of tempered glass can become problematic.
Design up to Specified Load. Window systems design (glazing, frames, anchorage to 
supporting walls, etc.) on the exterior facade should be balanced to mitigate the 
hazardous effects of flying debris in an explosive event. The walls, anchorage, and 
window framing should fully develop the capacity of the glazing material selected. 
The designer may use a combination of methods such as government produced and 
sponsored computer programs (e.g., Window Lite Analysis Code (WINLAC), Safety 
Viewport Analysis Code (SAFEVU), Blast-Resistant Window Program (BLASTOP), and 
Window Glazing Analysis Response and Design (WINGARD)) coupled with test data 
and recognized dynamic structural analysis techniques to show that the glazing 
either survives the specified threats or the post damage performance of the glazing 
protects the occupants in accordance with the conditions specified in Table 3-2. In 
general, laminated glass is the preferred glazing material for new construction. Tests 
have shown that laminated glass performs well under blast loads if mounted in 
properly designed window frames and it can be engineered to offer the highest levels 
of protection from glass fragments.  
Limitation of Glass Hazard Mitigation. Keep in mind that the pressures exerted on a 
building in a large explosion (e.g., a truck bomb) are often significantly greater than 
the pressures for which protected windows are designed. For these large events, the 
upgraded solutions may not be effective, except for windows on the sides of the 
building not facing the explosion or adjacent buildings. This is particularly true if 
structural damage occurs. Flying debris generated by structural damage typically 
causes more severe injuries than window damage alone; however, blast mitigating 
window designs are expected to be effective for a large number of threats where the 
pressures are low. Two such scenarios include a package bomb near the building and 
a truck bomb that goes off a block away.
Although these solutions do provide protection at modest pressure levels, they are not 
a "magic shield." The threat of attack still exists and injuries may still occur if an 
attack occurs. These measures will be most effective if considered a "last resort" 
measure used in conjunction with a full range of physical and operational security 
measures at the facility.
General Guidelines for Windows and Glazing. General guidelines for windows and 
glazing include the following:
_  Do not place windows adjacent to doors because, if the windows are broken, the 
doors can be unlocked.
_  Minimize the number and size of windows in a facade. If possible, limit the amount 
of glazed area in building facades to 15 percent. The amount of blast entering a 
space is directly proportional to the amount of openings on the facade.
_  Consider using burglary- and ballistic-resistant glazing in high-risk buildings.
_  Consider using laminated glass in place of conventional glass.
_  Consider window safety laminate (such as mylar) or another fragment retention 
film over glazing (properly installed) to reduce fragmentation.
_  Consider placing guards, such as grills, screens, or meshwork, across window 
openings to protect against covert entry. Affix protective window guards firmly to 
the structure.
_  Consider installing blast curtains, blast shades, or spall shields to prevent glass 
fragments from flying into the occupied space.
_  Consider curtains, blinds, and shades to limit entry of incendiary devices.
_  Consider narrow recessed windows with sloped sills because they are less vulnerable 
than conventional windows (see Figure 3-6).
_  Consider windows with key-operated locks because they provide a greater level of 
protection than windows with simple latches. Stationary, non-operating windows 
are preferred for security. 
_  Position the operable section of a sliding window on the inside of the fixed section 
and secure it with a broomstick, metal rod, or similar device placed at the bottom 
of the track. 
_  Provide horizontal windows 6 feet above the finished floor to limit entry.
_  Harden the windows by using steel window frames securely fastened or cement 
grouted to the surrounding structure.
Additional Glazing Requirements. Additional glazing requirements include the 
following:
_  Ballistic windows, if required, should meet the requirements of Underwriters 
Laboratory (UL) 752 Bullet-Resistant Glazing for a level appropriate for the 
project. Glassclad polycarbonate or laminated polycarbonate are two types of 
acceptable glazing material.
_  Security glazing, if required, should meet the requirements of the American Society 
for Testing and Materials (ASTM) F1233 or UL 972, Burglary-Resistant Glazing 
Material.
_  Glazing should meet the minimum performance specified in Table 3-2; however, 
special consideration should be given to frames and anchorages for ballistic-
resistant windows and security glazing because their inherent resistance to blast 
may impart large reaction.
_  Resistance of window assemblies to forced entry (excluding glazing) should meet 
the requirements of ASTM F 588 for a grade appropriate for the project.
_  Interior glazing should be minimized where a threat exists. The designer should 
avoid locating critical functions next to high-risk areas with glazing, such as 
lobbies, loading docks, etc.
Multi-hazard Considerations. Under normal operating conditions, windows function 
in a variety of ways, including:
_  Allowing light into a building
_  Conserving energy by reducing thermal transmission 
_  Reducing noise through acoustic transmission 
Explosions are one of a number of abnormal loading conditions that the building 
may be designed to mitigate. Some of the others are fire, earthquake, hurricane, 
gunfire, and forced entry.
In developing a protection strategy for windows to mitigate the effects of a particular 
explosion threat scenario, it is important to consider how this protection may 
interfere with some of these other functions or other explosion threat scenarios. 
Some questions that may be worthwhile to consider are:
_  If an internal explosion occurs, will the upgraded windows increase smoke 
inhalation injuries by preventing the smoke from venting through windows that 
would normally break in an explosion event?
_  If a fire occurs, will it be more difficult to break protected windows in order to vent 
the building and gain access to the injured?
_  Will a window upgrade that is intended to protect the occupants worsen the 
hazards to passersby?
3.3.4 Doors
A door system includes the door, frame, and anchorage to the building. As part of a 
balanced design approach, exterior doors in high-risk buildings should be designed 
to withstand the maximum dynamic pressure and duration of the load from the 
design threat explosive blast. Other general door considerations are as follows:
_  Provide hollow steel doors or steel-clad doors with steel frames.
_  Provide blast-resistant doors for high threats and high levels of protection.
_  Limit normal entry/egress through one door, if possible.
_  Keep exterior doors to a minimum while accommodating emergency egress. Doors 
are less attack-resistant than adjacent walls because of functional requirements, 
construction, and method of attachment. 
_  Ensure that exterior doors open outward from inhabited areas. In addition to 
facilitating egress, the doors can be seated into the door frames so that they will 
not enter the buildings as hazardous debris in an explosion.
_  Replace externally mounted locks and hasps with internally locking devices 
because the weakest part of a door system is the latching component. 
_  Install doors, where practical, so that they present a blank, flush surface to the 
outside to reduce their vulnerability to attack.
_  Locate hinges on the interior or provide concealed hinges to reduce their 
vulnerability to tampering.
_  Install emergency exit doors so that they facilitate only exiting movement.
_  Equip any outward-opening double door with protective hinges and key-operated 
mortise-type locks.
_  Provide solid doors or walls as a backup for glass doors in foyers.
_  Strengthen and harden the upright surfaces of door jambs.
3.3.5 Roof System Design
For an explosive threat, the primary loading on the roof is downward over-pressure. 
Secondary loads include upward pressure due to the blast penetrating through 
openings and upward suction during the negative loading phase. The upward 
pressures may have an increased duration due to multiple reflections of the air-blast 
internally. It is conservative to consider the downward and upward loads separately. 
The preferred system is to use poured-in-place reinforced concrete with beams in two 
directions. If this system is used, beams should have stirrups along the entire span 
spaced not greater than one half the beam depths. A second system uses steel frames 
with a concrete and metal deck slab to achieve higher levels of protection. For this 
system to work well, a two-way system of reinforcing bars spaced not more than the 
total thickness of the slab should be provided. Also, puddle welds or other robust 
systems are needed along the perimeter to resist the shear forces on the slab as it 
deflects downward. 
Less desirable systems include metal plate systems without concrete, and precast and 
pre/post tensioned systems. The metal plate system is prone to fail due to its light 
weight and direct pressure, or by the negative phase pressure that creates a suction 
effect on the roof. Precast panels are problematic because of the tendency to fail at 
the connections. Pre/post tensioned systems tend to fail in a brittle manner if 
stressed beyond their elastic limit and they also are not able to accept upward loads 
without additional reinforcement. If pre/post tensioned systems are used, continuous 
mild steel needs to be added to the top and the bottom faces to provide the flexibility 
needed to resist explosion loads.
Flat slab/plate systems are also less desirable because of limited two-way action and 
the potential of shear failure at the columns. 
Miscellaneous Roof System. Designers should consider the following:
_  Designing buildings with a sacrificial sloping roof that is above a protected ceiling 
(see Figure 3-7).
_  Controlling access to roofs to minimize the possibility of aggressors placing 
explosives or chemical, biological, or radiological agents there or otherwise 
threatening building occupants or critical infrastructure. For new buildings, 
eliminate all external roof access by providing access from internal stairways or 
ladders, such as in mechanical rooms. For existing buildings, eliminate external 
access where possible or make roof access ladders removable, retractable, or 
lockable.
_  Protecting roof openings to a facility from covert entry by installing screens or 
grates or attaching Intrusion Detection System sensors.
3.4 MECHANICAL SYSTEMS
Mechanical system design standards address limiting damage to critical 
infrastructure and protecting building occupants against CBR threats. The primary 
goal of a mechanical system after a terrorist attack should be to continue to operate 
key life safety systems. This can be accomplished by locating components in less 
vulnerable areas, limiting access to mechanical systems, and providing a reasonable 
amount of redundancy. Other aspects of mechanical systems are discussed in Section 
2.10.
During an interior bombing event, smoke removal and control are of paramount 
importance. The designer should consider the fact that, if window glazing is 
hardened, a blast may not blow out windows, and smoke may be trapped in the 
building. In the event of a blast, the available smoke removal system may be essential 
to smoke removal, particularly in large, open spaces. This equipment should be 
located away from high-risk areas (e.g., garages and loading docks). The system 
controls and power wiring to the equipment should be protected, and the system 
should be connected to emergency power to provide smoke removal. Smoke removal 
equipment should be provided with standalone local control panels that can 
continue to individually function in the event the control wiring is severed from the 
main control system.
Designers should consider the following:
_  Do not mount plumbing, electrical fixtures, or utility lines on the inside of 
exterior walls, but, when this is unavoidable, mount fixtures on a separate wall at 
least 6 inches from the exterior wall face.
_  Avoid placing plumbing on the roof slab.
_  Avoid suspending plumbing fixtures and piping from the ceiling.
_  Reduce the number of utility openings, manholes, tunnels, air conditioning ducts, 
filters, and access panels into the structure.
_  Locate utility systems away from likely areas of potential attack, such as loading 
docks, lobbies, and parking areas.
_  Protect building operational control areas and utility feeds to lessen the negative 
effects of a blast.
_  Design operational redundancies to survive all kinds of attack.
_  Use lockable systems for utility openings and manholes where appropriate. 
Infrequently used utility covers/manholes can be tack-welded as an inexpensive 
alternative to locking tamper-resistant covers.
Key HVAC System Considerations. The following HVAC design measures (from 
Centers for Disease Control and Prevention, National Institute for Occupational 
Safety and Health, Guidance for Protecting Building Environments from Airborne Chemical, 
Biological, or Radiological Attacks, May 2002) should be considered to mitigate the risk of 
CBR threats for high security buildings. HVAC protective actions are discussed in 
Chapter 5. 
_  Elevating the fresh-air intakes to reduce the potential for hazardous materials 
entering a building from a ground-level outdoor release is most easily applied in 
new construction (see Figures 3-8 and 3-9). This has two main benefits. The first 
benefit is that it provides passive security against malicious acts, which makes it 
more difficult for a container of hazardous material to be inserted directly into the 
buildings HVAC system and to be conveyed to various parts of the building. The 
second benefit is that it makes it less likely that high concentrations of hazardous 
material will occur at the intakes if there is a ground-level release near the 
building. 
_  Locating ground-level intakes near streets or parking areas can cause exhaust 
fumes to be drawn indoors under certain conditions of wind and stability (see 
Figure 3-10). In elevating the intakes, the dilution increases with the distance from 
the source. In stable conditions, contaminants released near the ground will likely 
remain close to the ground unless the airflow over the building lifts it upward. 
Contaminants that are heavier than air will also tend to remain close to the 
ground under calm conditions.
_  Placing intakes at the highest practical level on the building is beneficial. For 
protection against malicious acts, the intakes should also be covered by screens so 
that objects cannot be tossed into the intakes or into air wells from the ground 
(see Figure 3-10). Such screens should be sloped to allow thrown objects to roll or 
slide off the screen, away from the intake. Many existing buildings have air intakes 
that are located at or below ground level. For those that have wall-mounted or 
below-grade intakes close to the building, the intakes can be elevated by 
constructing a plenum or external shaft over the intake (see Figure 3-11). An 
extension height of 12 feet will place the intake out of reach of individuals without 
some assistance.
_  Effectively elevating intakes has practical limits. A plume or cloud of hazardous 
materials can reach the intakes, particularly if the source is large and distant. For 
low-rise buildings (i.e., those having a width more than twice the height), a plume 
originating at ground level near the building will travel over the building rather 
than around it; thus, the wind will convey contaminants to the top of the building, 
with some dilution occurring.
_  For existing buildings with air intakes below grade, at ground level, or wall-
mounted outside secure areas, some protection can be gained with physical 
security measures (e.g., placing fencing, surveillance cameras, and motion 
detectors around the intakes to facilitate monitoring by security personnel). These 
measures can help prevent malicious acts, but are less effective than elevating the 
intakes, because ground level releases under certain conditions can enter the 
intakes from points outside the area fenced or under surveillance.
_  Physical security for mechanical rooms to prevent the direct introduction of 
hazardous materials into the system of ducts that distributes air to the building 
should be maintained. This includes locking and controlling the access to all 
mechanical rooms containing HVAC equipment.
_  Public access to building roofs should be prevented. Access to the roof may allow 
entry to the building and access to air intakes and HVAC equipment (e.g., self-
contained HVAC units, laboratory or bathroom exhausts) located on the roof. 
From a physical security perspective, roofs are like other entrances to the building 
and should be secured appropriately. Roofs with HVAC equipment should be 
treated like mechanical areas. Fencing or other barriers should restrict access 
from adjacent roofs.
_  Access to building operation systems by outsiders should be restricted. A building 
staff member should escort maintenance workers throughout their service visit 
and should visually inspect their work before final acceptance of the service. 
Alternatively, building managers can ensure the reliability of pre-screened service 
personnel from a trusted contractor.
_   Access to information on building operations (including mechanical, electrical, 
vertical transport, fire and life safety, security system plans and schematics, and 
emergency operations procedures) should be strictly controlled. Such information 
should be released to authorized personnel through the development of an access 
list and controlled copy numbering.
_  To prevent widespread dispersion of a contaminant released within lobbies, 
mailrooms, and loading docks, their HVAC systems should be isolated and the 
areas maintained at a negative pressure relative to the rest of the building, but at 
positive pressure relative to the outdoors. Physical isolation of these areas (well-
sealed floor to roof-deck walls, sealed wall penetrations) is critical to maintaining 
the pressure differential. It requires special attention to ensure airtight boundaries 
between these areas and adjacent spaces. In some building designs (those having 
lobbies with elevator access, for example), establishing a negative pressure 
differential presents a challenge. A qualified mechanical engineer can assist in 
determining if the recommended isolation is feasible for a given building.
_  Large buildings usually have multiple HVAC zones, with each zone served by its 
own air handling unit and duct system. In practice, these zones are not completely 
separated if they are on the same floor. Air flows between zones through hallways, 
atria, and doorways that are normally left open. Isolating the separate HVAC zones 
minimizes the potential spread of an airborne hazard within a building, and 
reduces the number of people potentially exposed if an internal release occurs. 
Zone separation provides a limited benefit against an external release. It increases 
internal resistance to air movement that is produced by wind forces and chimney 
effect, therefore reducing the rate of infiltration. In essence, isolating zones divide 
the building into separate environments, limiting the effects of single release to 
an isolated portion of the building. Isolation of zones requires full-height walls 
between each zone and its adjacent zone and hallway.
_  Consider "shelter-in-place" rooms or areas where people can congregate in the 
event of an outdoor release. The goal is to create areas where outdoor air 
infiltration is very low. Usually such rooms will be in the inner part of the 
building in an area with no exterior windows. The rooms should have doors that 
are effective at preventing airflow and should contain staging supplies such as 
duct tape and plastic to help further seal the areas from the hallways. Typically, 
restrooms are a bad choice, because they have exhaust ducts that lead directly to 
the outside. Opening and closing a conventional hinged door can pump large 
amounts of air into the room. If practical, replace the door with a code compliant 
sliding door to reduce this effect. Shelter-in-place is discussed in detail in Section 
5.2. 
_  Many central HVAC systems have energy management and control systems that can 
regulate airflow and pressures within a building on an emergency response basis. 
Some fire alarm systems provide useful capabilities during CBR events. In some 
cases, the best response option (given sufficient warning) might be to shut off the 
buildings HVAC and exhaust system(s), thus avoiding the introduction of a CBR 
agent from outside. In other cases, interior pressure and airflow control may 
prevent the spread of a CBR agent released in the building and/or ensure the 
safety of egress pathways. The decision to install emergency HVAC control options 
should be made in consultation with a qualified mechanical engineer who 
understands the ramifications of various HVAC operating modes on building 
operation and safety systems. 
_  HVAC control may not be appropriate in all emergency situations. Protection from 
CBR attacks depends upon the design and operation of the HVAC system and the 
nature of the CBR agent release. Lobbies, loading docks, and mailrooms might be 
provided with manually operated exhaust systems, activated by trained personnel 
to remove contaminants in the event of a known release, exhausting air to an 
appropriate area. Manipulation of the HVAC system could minimize the spread of 
an agent. If an HVAC control plan is pursued, building personnel should be 
trained to recognize a terrorist attack and know when to initiate the control 
measures. For example, emergency egress stairwells should remain pressurized 
(unless they are known to contain the CBR source). Other areas, such as 
laboratories, clean rooms, or pressure isolation rooms in hospitals, may need to 
remain ventilated. All procedures and training associated with the control of the 
HVAC system should be addressed in the buildings Emergency Response Plan 
(ERP).
_  Ducted returns offer limited access points to introduce a CBR agent. The return 
vents can be placed in conspicuous locations, reducing the risk of an agent being 
secretly introduced into the return system. Non-ducted return air systems 
commonly use hallways or spaces above suspended ceilings as a return-air path or 
plenum. CBR agents introduced at any location above the suspended ceiling in a 
ceiling plenum return system will probably migrate back to the HVAC unit and, 
without highly efficient filtration for the particular agent, redistribute it to 
occupied areas. Buildings should be designed to minimize interaction between 
air-handling zones. This can be partially accomplished by limiting shared returns. 
Where ducted returns are not feasible or warranted, hold-down clips may be used 
for the accessible areas of suspended ceilings that serve as the return plenum. This 
issue is closely related to the isolation of lobbies and mailrooms, because shared 
returns are a common way for contaminants from these areas to disperse into the 
rest of the building. These modifications may be more feasible for new building 
construction or those undergoing major renovation.
_  A rapid response, such as shutting down an HVAC system, may involve closing 
various dampers, especially those controlling the flow of outdoor air (in the event 
of an exterior CBR release). When the HVAC system is turned off, the building 
pressure compared to outdoors may still be negative, drawing outdoor air into the 
building via many leakage pathways, including the HVAC system. Consideration 
should be given to installing low leakage dampers to minimize this flow pathway. 
Damper leakage ratings are available as part of the manufacturers specifications 
and range from ultra-low to normal categories. Assuming that there is some 
warning prior to a direct CBR release, the speed with which these dampers 
respond to a "close" instruction can also be important. From a protective 
standpoint, dampers that respond quickly are preferred over dampers that might 
take 30 seconds or more to respond.
Emergency Plans, Training, and Procedures for HVAC Systems. All buildings should 
have current emergency plans to address fire, weather, and other types of 
emergencies. In light of past U.S. experiences with anthrax and similar threats, these 
plans should be updated to consider CBR attack scenarios and the associated 
procedures. Emergency plans should have procedures for communicating 
instructions to building occupants, identifying suitable shelter-in-place areas (if they 
exist), identifying appropriate use and selection of personal protective equipment 
(i.e., clothing, gloves, respirators), and directing emergency evacuations. Individuals 
developing emergency plans and procedures should recognize that there are 
fundamental differences between chemical, biological, and radiological agents. In 
general, chemical agents will show a rapid onset of symptoms, while the response to 
biological and radiological agents will be delayed. Issues such as designated areas 
and procedures for chemical storage, HVAC control or shutdown, and 
communications with building occupants and emergency responders, should all be 
addressed. The plans should be as comprehensive as possible, but, as described 
earlier, protected by limited and controlled access. When appropriately developed, 
these plans, policies, and procedures can have a major impact upon occupant 
survivability in the event of a CBR release. Staff training, particularly for those with 
specific responsibilities during an event, is essential and should cover both internal 
and external events. Holding regularly scheduled practice drills, similar to the 
common fire drill, allows for plan testing, as well as occupant and key staff rehearsal 
of the plan, and increases the likelihood for success in an actual event. For 
protection systems in which HVAC control is done via the energy management and 
control system, emergency procedures should be exercised periodically to ascertain 
that the various control options work (and continue to work) as planned.
Periodic training of HVAC maintenance staff in system operations and maintenance 
should be conducted. This training should include the procedures to be followed in 
the event of a suspected CBR agent release. Training should also cover health and 
safety aspects for maintenance personnel, as well as the potential health 
consequences to occupants of poorly performing systems. Development of current, 
accurate HVAC diagrams and HVAC system labeling protocols should be addressed. 
These documents can be of great value in the event of a CBR release.
Procedures and preventive maintenance schedules should be implemented for 
cleaning and maintaining ventilation system components. Replacement filters, parts, 
etc., should be obtained from known manufacturers and examined prior to 
installation. It is important that ventilation systems be maintained and cleaned 
according to the manufacturers specifications. To do this requires information on 
HVAC system performance, flow rates, damper modulation and closure, sensor 
calibration, filter pressure loss, filter leakage, and filter change-out 
recommendations. These steps are critical to ensure that protection and mitigation 
systems, such as particulate filtration, operate as intended.
3.5 ELECTRICAL SYSTEMS
The major security functions of the electrical system are to maintain power to 
essential building services, especially those required for life safety and evacuation; 
provide lighting and surveillance to deter criminal activities; and provide emergency 
communications. Thus, the operability of electrical systems is an important element 
for deferring terrorist attacks and can become a critical component for life safety 
systems after an attack. Designers should consider the following recommendations 
for buildings requiring high security:
_  Emergency and normal electric panels, conduits, and switchgear should be 
installed separately, at different locations, and as far apart as possible. Electric 
distribution should be run from separate locations.
_  Emergency generators should be located away from loading docks, entrances, and 
parking. More secure locations include the roof, protected grade level, and 
protected interior areas. 
_  Fuel tanks should be mounted near the generator, given the same protection as the 
emergency generator, and sized to store an appropriate amount of fuel. A battery 
and/or UPS could serve a smaller building or leased facility.
_  Conduits and lines should be installed outside to allow a trailer-mounted generator 
to connect to the buildings electrical system. If tertiary power is required, other 
methods include generators and feeders from alternative substations.
_  Site lighting should be coordinated with the CCTV system.
_  Emergency lighting should be provided in restrooms.
_  Building access points should be illuminated to aid in threat detection. 
_  Self-contained battery lighting should be provided in stairwells and for exit signs.
_  Suspending electrical conduits from the ceiling should be avoided.
_  Adequate lighting of perimeters and parking areas should be provided to aid in 
visual surveillance and to support the use of physical security systems.
3.6 FIRE PROTECTION SYSTEMS
The fire protection system inside the building should maintain life safety protection 
after an incident and allow for safe evacuation of the building when appropriate. 
Although fire protection systems are designed to perform well during fires, they are 
not traditionally designed to survive bomb blasts. To enhance the performance of fire 
protection systems, especially in the case of an explosive blast, the designer should 
consider the following:
_  The fire protection water system should be protected from single-point failure in 
case of a blast event. The incoming line should be encased, buried, or located 50 
feet away from high-risk areas. The interior mains should be looped and 
sectionalized.
_  To increase the reliability of the fire protection system in strategic locations, a dual 
pump arrangement should be considered, with one electric pump and one diesel 
pump. The pumps should be located away from each other.
_  All security locking arrangements on doors used for egress must comply with 
requirements of the National Fire Protection Association (NFPA) 101, Life Safety 
Code.
3.7COMMUNICATIONS SYSTEMS
For buildings requiring greater protection, the designer should consider the 
following:
_  Redundant communications. The facility could have a second telephone service to 
maintain communications in case of an incident. A base radio communication 
system with antenna should be installed in the stairwell, and portable sets 
distributed on floors. This is the preferred alternative.
_  Radio telemetry. Distributed antennas could be located throughout the facility if 
required for emergency communications through wireless transmission of data.
_  Alarm and information systems. Alarm and information systems should not be 
collected and mounted in a single conduit, or even collocated. Circuits to various 
parts of the building should be installed in at least two directions and/or risers. 
Low voltage signal and control copper conductors should not share conduits with 
high voltage power conductors. Fiber-optic conductors are generally preferred 
over copper.
_  Empty conduits. Empty conduits and power outlets can be provided for future 
installation of security control equipment.
_  Mass notification. All inhabited buildings should have a timely means to notify 
occupants of threats and give instructions as to responses. Building 
communications systems should provide real-time notification of occupants and 
passersby in the immediate vicinity of the building during emergency situations. 
The information relayed should be specific enough to determine the appropriate 
response actions.
3.8 ELECTRONIC SECURITY SYSTEMS
Electronic security, including surveillance, intrusion detection, and screening, is a 
key element of facility protection. Many aspects of electronic security and the posting 
of security personnel have been adequately dealt with in other criteria and guideline 
documents. These criteria primarily address access control design, including stair 
and lobby design, because access control must be considered when design concepts 
for a building are first conceived. Although fewer options are available for 
modernization projects, some designs can be altered to consider future access control 
objectives.
The purpose of electronic security is to improve the reliability and effectiveness of life 
safety systems, security systems, and building functions. When possible, 
accommodations should be made for future developments in security systems.
This chapter is not a design guide for Electronic Security Systems (ESS). The 
following criteria are only intended to stress those concepts and practices that 
warrant special attention to enhance public safety. Consult design guides pertinent to 
the specific project for detailed information about electronic security. A description 
of Electronic Security Systems is provided in Appendix D.
For control centers and building management systems, designers should consider 
the following:
_ The Operational Control Center (OCC), Fire Command Center (FCC), and Security 
Control Center (SCC) may be collocated. If collocated, the chain of command 
should be carefully pre-planned to ensure the most qualified leadership is in 
control for specific types of events. Secure information links should be provided 
between the OCC, FCC, and SCC.
_  A Backup Control Center (BCC) should be provided in a different location, such as 
a manager's or engineer's office. If feasible, an off-site location should be 
considered.
_ A fully redundant BCC should be installed (this is an alternative to the above).
_ Basic intrusion detection devices should be provided: magnetic reed switches for 
interior doors and openings, glass break sensors for windows up to scalable 
heights, and balanced magnetic contact switch sets for all exterior doors, 
including overhead/roll-up doors. Roof intrusion detection should be reviewed.
_ Monitoring should be done at an off-site facility.
_ An on-site monitoring center should be used during normal business hours and be 
operational 24 hours.
_ A color CCTV surveillance system with recording capability should be provided to 
view and record activity at the perimeter of the building, particularly at primary 
entrances and exits. A mix of monochrome cameras should be considered for 
areas that lack adequate illumination for color cameras.
The following considerations apply when lighting systems are intended to support 
CCTV assessment or surveillance: field of view of the camera; lighting intensity levels; 
maximum light-to-dark ratio; scene reflectance; daylight-to-darkness transitions; 
camera mounting systems relative to lighting; spectral response of the camera; cold-
start time; and restrike time.
3.9ENTRY-CONTROL STATIONS
Entry-control stations should be provided at main perimeter entrances where security 
personnel are present (see Figure 3-12). In addition, entry-control stations should be 
located close to the perimeter entrance to permit people inside the station to 
maintain constant surveillance over the entrance and its approaches. Additional 
considerations at entry-control stations include:
_  A holding area for unauthorized vehicles or those needing further inspection 
should be established. A turnaround area should be provided so that traffic is not 
impeded.
_  Control measures such as displaying a decal on the window or having a specially 
marked vehicle should be established.
_  Entry-control stations that are manned 24 hours each day should have interior and 
exterior lighting, interior heating and cooling (where appropriate), and a 
sufficient glassed area to afford adequate observation for people inside. Where 
appropriate, entry-control stations should be designed for optimum personnel ID 
and movement control. Each station should include a telephone, a radio, and 
badge racks (if required).
_  Signs should be erected to assist in controlling authorized entry, to deter 
unauthorized entry, and to preclude accidental entry. Signs should be plainly 
displayed and legible from any approach to the perimeter from a reasonable 
distance. The size and coloring of a sign, its letters, and the interval of posting 
must be appropriate to each situation.
_  Entry-control stations should be hardened against attacks according to the type of 
threat. The methods of hardening may include:
  Reinforced concrete or masonry
  Steel plating
  Bullet-resistant glass
  Commercially fabricated, bullet-resistant building components or 
assemblies

3.10PHYSICAL SECURITY SYSTEMS
Physical security concerns the physical measures designed to safeguard people; 
prevent unauthorized access to equipment, installations, material, and documents; 
and safeguard against terrorist attacks. As such, all security operations face new and 
complex physical security challenges across the full spectrum of operations. 
Challenges relative to physical security include the control of populations, 
information dominance, multi-national and interagency connectivity, antiterrorism, 
and the use of physical security assets as a versatile force multiplier.
The rapid evolution of physical security equipment technology leads to physical 
security challenges, which are exponentially multiplied by the introduction of the 
information age (see Appendix D). Physical security challenges must be understood, 
and measures must be taken to minimize them to enhance the protection of people 
within a facility. 
3.11 SUMMARY OF BUILDING ENVELOPE MITIGATION MEASURES
A general spectrum of building envelope mitigation measures ranging from the least 
protection, cost, and effort going to the greatest protection, cost, and effort is 
provided below. Detailed discussions of individual measures can be found earlier in 
the chapter. Please note this is a nominal ranking of mitigation measures. In 
practice, the effectiveness and cost of individual mitigation measures may deviate 
from this example based on specific applications. 

   Ensure that exterior doors into inhabited areas open outward. Ensure emergency exit doors only facilitate 
exiting.
   Secure roof access hatches from the interior. Prevent public access to building roofs.
   Restrict access to building operation systems.
   Conduct periodic training of HVAC operations and maintenance staff.
   Evaluate HVAC control options. 
   Install empty conduits for future security control equipment during initial construction or major renovation.
   Do not mount plumbing, electrical fixtures, or utility lines on the inside of exterior walls.
   Minimize interior glazing near high-risk areas.
   Establish emergency plans, policies, and procedures.
   Establish written plans for evacuation and sheltering in place.
   Illuminate building access points.
   Restrict access to building information.
   Secure HVAC intakes and mechanical rooms.
   Limit the number of doors used for normal entry/egress.
   Lock all utility access openings.
   Provide emergency power for emergency lighting in restrooms, egress routes, and any meeting room without 
windows.
   Install an internal public address system.
   Stagger interior doors and offset interior and exterior doors.
   Eliminate hiding places.
   Install a second and separate telephone service.
   Install radio telemetry distributed antennas throughout the facility.
   Use a badge identification system for building access.
   Install a CCTV surveillance system.
   Install an electronic security alarm system.
   Install rapid response and isolation features into HVAC systems.
   Use interior barriers to differentiate levels of security.
   Locate utility systems away from likely areas of potential attack.
   Install call buttons at key public contact areas.
   Install emergency and normal electric equipment at different locations.
   Avoid exposed structural elements.
   Reinforce foyer walls.
   Use architectural features to deny contact with exposed primary vertical load members.
   Isolate lobbies, mailrooms, loading docks, and storage areas.
   Locate stairwells remotely. Do not discharge stairs into lobbies, parking, or loading areas.
   Elevate HVAC fresh-air intakes.
   Create "shelter-in-place" rooms or areas.
   Separate HVAC zones. Eliminate leaks and increase building air tightness.
   Install blast-resistant doors or steel doors with steel frames. 
   Physically separate unsecured areas from the main building.
   Install HVAC exhausting and purging systems.
   Connect interior non-load bearing walls to structure with non-rigid connections.
   Use structural design techniques to resist progressive collapse.
   Treat exterior shear walls as primary structures.
   Orient glazing perpendicular to the primary faade facing uncontrolled vehicle approaches.
   Use reinforced concrete wall systems in lieu of masonry or curtain walls.
   Ensure active fire system is protected from single-point failure in case of a blast event.
   Install a Backup Control Center (BCC).
   Avoid eaves and overhangs or harden to withstand blast effects.
   Establish ground floor elevation 4 feet above grade.
   Avoid re-entrant corners on the building exterior.
 



Leadership in Energy and Environmental Design (LEED)
As with CPTED, some of the Leadership in Energy and Environmental Design (LEED) concepts 
complement security concerns and others conflict with physical security principles. The LEED Green 
Building Rating System represents the U.S. Green Building Councils (USGBCs) effort to provide a 
national standard for what constitutes a "green building." Through its use as a design guideline and 
third-party certification tool, it aims to improve occupant well-being, environmental performance, and 
economic returns of buildings using established and innovative practices, standards, and 
technologies.1 LEED is a voluntary building assessment tool that is most applicable to commercial, 
institutional, and high-rise residential construction. Owners, architects, and engineers must work 
together to strike a balance between building design objectives.
LEED looks at six basic categories: Sustainable Sites, Water Efficiency, Energy and Atmosphere, 
Materials and Resources, Indoor Environmental Quality, and Innovation and Design Process. Within 
each category, points are awarded for achieving specific goals. A total of 69 points is possible. A 
score of 26-32 points achieves basic certification; 33-38 achieves Silver; 39-51 achieves Gold; and 
52-69 points achieve Platinum certification. The LEED rating is awarded after the project has been 
documented by the USGBC.
Another goal in the LEED effort is to encourage more sustainable construction practices. LEED 
encourages manufacturers to provide materials that:
_  contain high recycled content and sustainable use raw materials
_  are manufactured close to the construction site
_  have low volatile organic compound emissions
_  are designed to minimize energy consumption and packaging
1  U.S. Green Building Council, LEED Green Building Rating System for New Construction & Major      Renovations Version 2.1, November 
2002. http://www.usgbc.or


SOURCE: U.S. AIR FORCE, INSTALLATION FORCE PROTECTION GUID


Figure 3-1 Glazed areas perpendicularly oriented away from street


SOURCE: U.S. AIR FORCE, INSTALLATION FORCE PROTECTION GUID


Figure 3-2 Re-entrant corners in a floor pla


SOURCE: U.S. AIR FORCE, INSTALLATION FORCE PROTECTION GUID


Figure 3-3 Offset doors through foye


The following additional references are recommended:
_  Biggs, John M. Introduction to Structural Dynamics. McGraw-Hill. (1964).
_  The Institute of Structural Engineers. The Structural Engineers Response to Explosive Damage. 
SETO, Ltd., 11 Upper Belgrave Street, London SW1X8BH. (1995).
_  Mays, G.S. and Smith, P.D. Blast Effects on Buildings: Design of Buildings to Optimize 
Resistance to Blast Loading. Thomas Telford Publications, 1 Heron Quay, London E14 4JD. 
(1995).
_  National Research Council. Protecting Buildings from Bomb Damage. National Academy Press. 
(1995).


Table 3-1: Glazing Protection Levels Based on Fragment Impact Locations1

PerformanceConditio
n
ProtectionLev
el
HazardLev
el
Description of WindowGlazing 
Response
1
Safe
None
Glazing does not break. No visible 
damage to glazing or frame.
2*
Very High
None
Glazing cracks, but is retained by the 
frame. Dusting or very small fragments 
near sill or on floor acceptable. 
3a*
High
Very Low
Glazing cracks. Fragments enter space 
and land on floor no more than 3.3 feet 
from the window.
3b*
High
Low
Glazing cracks. Fragments enter space 
and land on floor no more than 10 feet 
from the window.
4*
Medium
Medium
Glazing cracks. Fragments enter space 
and land on floor and impact a vertical 
witness panel at a distance of no more 
than 10 feet from the window at a height 
no greater than 2 feet above the floor.
5*
Low
High
Glazing cracks and window system fails 
catastrophically. Fragments enter space, 
impacting a vertical witness panel at a 
distance of no more than 10 feet from the 
window at a height greater than 2 feet 
above the floor.



*  In conditions 2, 3a, 3b, 4 and 5, glazing fragments may be thrown to the outside of the protected 
space toward the detonation location.



1   From GSA PBS-PQ100.1, Facilities Standards for the Public Building Service, June 14, 199


Figure 3-4 Side view of a test structure illustrating performance conditions of Table 3-


Table 3-2: Correlation of GSA Glazing Performance Conditions and DoD Levels of Protection for 
New Buildings

GSA Glazing Performance 
Condition
Corresponding DoD Level of Protection for New 
Buildings
1
High
2
Medium
3a
Low
3b/4
Very Low
5
Below antiterrorism (AT) Standards


Figure 3-5 An unprotected window subject to a large explosio


Figure 3-6 Narrow and recessed windows with sloped sill


SOURCE: U.S. AIR FORCE, INSTALLATION FORCE PROTECTION GUID


Figure 3-7 Sacrificial roo


Figure 3-8 Example of protecting outdoor air intake


SOURCE: CDC/NIOSH, PUBLICATION NO. 2002-139, GUIDANCE FOR PROTECTING BUILDING ENVIRONMENTS FROM AIRBORNE 
CHEMICAL, BIOLOGICAL, OR RADIOLOGICAL ATTACKS, MAY 200


Figure 3-9 Example of elevated air intak


SOURCE: CDC/NIOSH, PUBLICATION NO. 2002-139, GUIDANCE FOR PROTECTING BUILDING ENVIRONMENTS FROM AIRBORNE 
CHEMICAL, BIOLOGICAL, OR RADIOLOGICAL ATTACKS, MAY 200


Figure 3-10 Another example of protecting outdoor air intake


SOURCE: CDC/NIOSH, PUBLICATION NO. 2002-139, GUIDANCE FOR PROTECTING BUILDING ENVIRONMENTS FROM AIRBORNE 
CHEMICAL, BIOLOGICAL, OR RADIOLOGICAL ATTACKS, MAY 200


Figure 3-11 Example of enclosing an existing vulnerable air intak


Ground-level Outdoor Air Intak


Raised-level Outdoor Air Intak


SOURCE: CDC/NIOSH, PUBLICATION NO. 2002-139, GUIDANCE FOR PROTECTING BUILDING ENVIRONMENTS FROM AIRBORNE 
CHEMICAL, BIOLOGICAL, OR RADIOLOGICAL ATTACKS, MAY 200


Figure 3-12 Physical security device


Continued on next pag




EXPLOSIVE BLAST     


This chapter discusses blast effects, building damage, injuries, levels of 
protection, stand-off distance, and predicting blast effects. Specific blast design 
concerns and mitigation measures are discussed in Chapters 2 and 3. Explosive events 
have historically been a favorite tactic of terrorists for a variety of reasons and this is 
likely to continue into the future. Ingredients for homemade bombs are easily 
obtained on the open market as are the techniques for making bombs. Also, 
explosive events are easy and quick to execute. Vehicle bombs have the added 
advantage of being able to bring a large quantity of explosives to the doorstep of the 
target undetected. Finally, terrorists often attempt to use the dramatic component of 
explosions, in terms of the sheer destruction they cause, to generate media coverage 
in hopes of transmitting their political message to the public. The DoD, GSA, and 
DOS have considerable experience with blast effects and blast mitigation. However, 
many architects and building designers do not have such experience. For additional 
information on explosive blast, see FEMA 427, Primer for Design of Commercial Buildings to 
Mitigate Terrorist Attacks.
4.1 BLAST EFFECTS
When a high order explosion is initiated, a very rapid exothermic chemical reaction 
occurs. As the reaction progresses, the solid or liquid explosive material is converted 
to very hot, dense, high-pressure gas. The explosion products initially expand at very 
high velocities in an attempt to reach equilibrium with the surrounding air, causing 
a shock wave. A shock wave consists of highly compressed air, traveling radially 
outward from the source at supersonic velocities. Only one-third of the chemical 
energy available in most high explosives is released in the detonation process. The 
remaining two-thirds is released more slowly as the detonation products mix with air 
and burn. This afterburning process has little effect on the initial blast wave because 
it occurs much slower than the original detonation. However, later stages of the blast 
wave can be affected by the afterburning, particularly for explosions in confined 
spaces. As the shock wave expands, pressures decrease rapidly (with the cube of the 
distance) because of geometric divergence and the dissipation of energy in heating 
the air. Pressures also decay rapidly over time (i.e., exponentially) and have a very brief 
span of existence, measured typically in thousandths of a second, or milliseconds . An 
explosion can be visualized as a "bubble" of highly compressed air that expands until 
reaching equilibrium with the surrounding air.
Explosive detonations create an incident blast wave, characterized by an almost 
instantaneous rise from atmospheric pressure to a peak overpressure. As the shock 
front expands pressure decays back to ambient pressure, a negative pressure phase 
occurs that is usually longer in duration than the positive phase as shown in Figure 4-
1. The negative phase is usually less important in a design than the positive phase.
When the incident pressure wave impinges on a structure that is not parallel to the 
direction of the waves travel, it is reflected and reinforced, producing what is known 
as reflected pressure. The reflected pressure is always greater than the incident 
pressure at the same distance from the explosion. The reflected pressure varies with 
the angle of incidence of the shock wave. When the shock wave impinges on a 
surface that is perpendicular to the direction it is traveling, the point of impact will 
experience the maximum reflected pressure. When the reflecting surface is parallel to 
the blast wave, the minimum reflected pressure or incident pressure will be 
experienced. In addition to the angle of incidence, the magnitude of the peak 
reflected pressure is dependent on the peak incident pressure, which is a function of 
the net explosive weight and distance from the detonation.
Figure 4-2 shows typical reflected pressure coefficients versus the angle of incidence 
for four different peak incident pressures. The reflected pressure coefficient equals 
the ratio of the peak reflected pressure to the peak incident pressure (Cr = Pr / Pi). 
This figure shows that reflected pressures for explosive detonations can be almost 13 
times greater than peak incident pressures and, for all explosions, the reflected 
pressure coefficients are significantly greater closer to the explosion.
Impulse is a measure of the energy from an explosion imparted to a building. Both 
the negative and positive phases of the pressure-time waveform contribute to impulse. 
Figure 4-3 shows how impulse and pressure vary over time from a typical explosive 
detonation. The magnitude and distribution of blast loads on a structure vary greatly 
with several factors:
_		Explosive properties (type of material, energy output, and quantity of 
explosive)
_		Location of the detonation relative to the structure
_		Reinforcement of the pressure pulse through its interaction with the ground 
or structure (reflections)
The reflected pressure and the reflected impulse are the forces to which the building 
ultimately responds. These forces vary in time and space over the exposed surface of 
the building, depending on the location of the detonation in relation to the 
building. Therefore, when analyzing a structure for a specific blast event, care should 
be taken to identify the worst case explosive detonation location.
In the context of other hazards (e.g., earthquakes, winds, or floods), an explosive 
attack has the following distinguishing features:
_		The intensity of the pressures acting on a targeted building can be several 
orders of magnitude greater than these other hazards. It is not uncommon for the 
peak incident pressure to be in excess of 100 psi on a building in an urban setting 
for a vehicle weapon parked along the curb. At these pressure levels, major 
damages and failure are expected. 
_		Explosive pressures decay extremely rapidly with distance from the source. 
Therefore, the damages on the side of the building facing the explosion may be 
significantly more severe than on the opposite side. As a consequence, direct air-
blast damages tend to cause more localized damage. In an urban setting, however, 
reflections off surrounding buildings can increase damages to the opposite side.
_		The duration of the event is very short, measured in thousandths of a second, 
or milliseconds. This differs from earthquakes and wind gusts, which are 
measured in seconds, or sustained wind or flood situations, which may be 
measured in hours. Because of this, the mass of the structure has a strong 
mitigating effect on the response because it takes time to mobilize the mass of the 
structure. By the time the mass is mobilized, the loading is gone, thus mitigating 
the response. This is the opposite of earthquakes, whose imparted forces are 
roughly in the same timeframe as the response of the building mass, causing a 
resonance effect that can worsen the damage.
4.1.1 Building Damage
The extent and severity of damage and injuries in an explosive event cannot be 
predicted with perfect certainty. Past events show that the unique specifics of the 
failure sequence for a building significantly affect the level of damage. Despite these 
uncertainties, it is possible to give some general indications of the overall level of 
damage and injuries to be expected in an explosive event, based on the size of the 
explosion, distance from the event, and assumptions about the construction of the 
building. 
Damage due to the air-blast shock wave may be divided into direct air-blast effects and 
progressive collapse. Direct air-blast effects are damage caused by the high-intensity 
pressures of the air-blast close in to the explosion and may induce the localized 
failure of exterior walls, windows, floor systems, columns, and girders. A discussion of 
progressive collapse can be found in Chapter 3.
The air blast shock wave is the primary damage mechanism in an explosion. The 
pressures it exerts on building surfaces may be several orders of magnitude greater 
than the loads for which the building is designed. The shock wave also acts in 
directions that the building may not have been designed for, such as upward on the 
floor system. In terms of sequence of response, the air-blast first impinges on the 
weakest point in the vicinity of the device closest to the explosion, typically the 
exterior envelope of the building. The explosion pushes on the exterior walls at the 
lower stories and may cause wall failure and window breakage. As the shock wave 
continues to expand, it enters the structure, pushing both upward and downward on 
the floors (see Figure 4-4).
Floor failure is common in large-scale vehicle-delivered explosive attacks, because 
floor slabs typically have a large surface area for the pressure to act on and a 
comparably small thickness. In terms of the timing of events, the building is 
engulfed by the shock wave and direct air-blast damage occurs within tens to 
hundreds of milliseconds from the time of detonation. If progressive collapse is 
initiated, it typically occurs within seconds.
Glass is often the weakest part of a building, breaking at low pressures compared to 
other components such as the floors, walls, or columns. Past incidents have shown 
that glass breakage may extend for miles in large external explosions. High-velocity 
glass fragments have been shown to be a major contributor to injuries in such 
incidents. For incidents within downtown city areas, falling glass poses a major 
hazard to passersby on the sidewalks below and prolongs post-incident rescue and 
cleanup efforts by leaving tons of glass debris on the street. Specific glazing design 
considerations are discussed in Chapter 3.
4.1.2 Injuries
Severity and type of injury patterns incurred in explosive events may be related to the 
level of structural damage. The high pressure of the air-blast that enters through 
broken windows can cause eardrum damage and lung collapse. As the air-blast 
damages the building components in its path, missiles are generated that cause 
impact injuries. Airborne glass fragments typically cause penetration or laceration-
type injuries. Larger fragments may cause non-penetrating, or blunt trauma, injuries. 
Finally, the air-blast pressures can cause occupants to be bodily thrown against 
objects or to fall. Lacerations due to high-velocity flying glass fragments have been 
responsible for a significant portion of the injuries received in explosion incidents. 
In the bombing of the Murrah Federal Building in Oklahoma City, for instance, 40 
percent of the survivors in the Murrah Federal Building cited glass as contributing to 
their injuries. Within nearby buildings, laceration estimates ranged from 25 percent 
to 30 percent.
4.1.3 Levels of Protection
The amount of explosive and the resulting blast dictate the level of protection 
required to prevent a building from collapsing or minimizing injuries and deaths. 
Table 4-1 shows how the DoD correlates levels of protection with potential damage 
and expected injuries. The GSA and the Interagency Security Committee (ISC) also 
use the level of protection concept. However, wherein the DoD has five levels, they 
have established four levels of protection. The GSA and ISC levels of protection can be 
found in GSA PBS-P100, Facilities Standards for the Public Buildings Service, November 2000, 
Section 8.6.
The levels of protection above can roughly be correlated for conventional 
construction without any blast hardening to the incident pressures shown in Table 4-
2.
Table 4-2: Correlation of DoD Level of Protection to Incident Pressure

Level of 
Protection
Incident Pressure 
(psi)
High
1.1
Medium
1.8
Low
2.3

Figure 4-5 shows an example of a range-to-effect chart that indicates the distance or 
stand-off to which a given size bomb will produce a given effect (see Section 4.2). This 
type of chart can be used to display the blast response of a building component or 
window at different levels of protection. It can also be used to consolidate all building 
response information to assess needed actions if the threat weapon-yield changes. 
For example, an amount of explosives are stolen and indications are that they may be 
used against a specific building. A building-specific range-to-effect chart will allow 
quick determination of the needed stand-off for the amount of explosives in question, 
after the explosive weight is converted to TNT equivalence. 
Research performed as part of the threat assessment process should identify bomb 
sizes used in the locality or region. Security consultants have valuable information 
that may be used to evaluate the range of likely charge weights. Given an explosive 
weight and a stand-off distance, Figure 4-5 can be used to predict damage for nominal 
building construction.
Figures 4-6 and 4-7 show blast effects predictions for a building based on a typical car 
bomb and a typical large truck bomb detonated in the buildings parking lot, 
respectively. A computer-based Geographic Information System (GIS) was used to 
analyze the building's vehicular access and circulation pattern to determine a 
reasonable detonation point for a vehicle bomb. Structural blast analysis was then 
performed using nominal explosive weights and a nominal building structure. The 
results are shown in Figures 4-6 and 4-7. The red ring indicates the area in which 
structural collapse is predicted. The orange and yellow rings indicate predictions for 
lethal injuries and severe injuries from glass, respectively. Please note that nominal 
inputs were used in this analysis and they are not a predictive examination.
In the case of a stationary vehicle bomb, knowing the size of the bomb (TNT 
equivalent in weight), its distance from the structure, how the structure is put 
together, and the materials used for walls, framing, and glazing allows the designer 
to determine the level of damage that will occur and the level of protection achieved. 
Whether an existing building or a new construction, the designer can then select 
mitigation measures as presented in this chapter and in Chapters 2 and 3 to achieve 
the level of protection desired.
4.2 STAND-OFF DISTANCE AND THE EFFECTS OF BLAST   
Energy from a blast decreases rapidly over distance. In general, the cost to provide 
asset protection will decrease as the distance between an asset and a threat increases, 
as shown in Figure 4-8. However, increasing stand-off also requires more land and 
more perimeter to secure with barriers, resulting in an increased cost not reflected in 
Figure 4-8. As stand-off increases, blast loads generated by an explosion decrease and 
the amount of hardening necessary to provide the required level of protection 
decreases. Figure 4-9 shows how the impact of a blast will decrease as the stand-off 
distance increases, as indicated in the blast analysis of the Khobar Towers incident. 
Increasing the stand-off distance from 80 to 400 feet would have significantly limited 
the damage to the building and hazard to occupants, the magnitude of which is 
shown as the yellow and red areas in Figure 4-9. Additional concepts of stand-off 
distance are discussed in Section 2.3. 
The critical location of the weapon is a function of the site, the building layout, and 
the security measures in place. For vehicle bombs, the critical locations are 
considered to be at the closest point that a vehicle can approach on each side, 
assuming that all security measures are in place. Typically, this is a vehicle parked 
along the curb directly outside the building, or at the entry control point where 
inspection takes place. For internal weapons, location is dictated by the areas of the 
building that are publicly accessible (e.g., lobbies, corridors, auditoriums, cafeterias, 
or gymnasiums). Range or stand-off is measured from the center of gravity of the 
charge located in the vehicle or other container to the building component under 
consideration. 
Defining appropriate stand-off distance for a given building component to resist 
explosive blast effects is difficult. Often, in urban settings, it is either not possible or 
practical to obtain appropriate stand-off distance. Adding to the difficulty is the fact 
that defining appropriate stand-off distance requires a prediction of the explosive 
weight of the weapon. In the case of terrorism, this is tenuous at best.
The DoD prescribes minimum stand-off distances based on the required level of 
protection. Where minimum stand-off distances are met, conventional construction 
techniques can be used with some modifications. In cases where the minimum stand-
off cannot be achieved, the building must be hardened to achieve the required level 
of protection (see Unified Facilities Criteria  DoD Minimum Antiterrorism 
Standards for Buildings, UFC 4-010-01, 31 July 2002).
The GSA and ISC Security Criteria do not require or mandate specific stand-off 
distances. Rather, they provide protection performance criteria. In order to 
economically meet these performance standards, they present recommended stand-
off distances for vehicles that are parked on adjacent properties and for vehicles that 
are parked on the building site (see GSA Security Criteria, Draft Revision, October 8, 1997, 
and ISC Security Design Criteria for New Federal Office Buildings and Major Modernization 
Projects, May 28, 2001). 
Site and layout design guidance as well as specific mitigation measures to enhance 
stand-off and enhance protection from explosive blast are discussed in Chapter 2. 
4.3 PREDICTING BLAST EFFECTS
4.3.1 Blast Load Predictions
The first step in predicting blast effects on a building is to predict blast loads on the 
structure. For a detonation that is exterior to a building, it is the blast pressure pulse 
that causes damage to the building. Because the pressure pulse varies based on stand-
off distance, angle of incidence, and reflected pressure over the exterior of the 
building, the blast load prediction should be performed at multiple threat locations; 
however, worse case conditions are normally used for decision-making.
For complex structures requiring refined estimates of blast load, blast consultants 
may use sophisticated methods such as Computational Fluid Dynamics (CFD) 
computer programs to predict blast loads. These complex programs require special 
equipment and training to run.
In most cases, especially for design purposes, more simplified methods may be used 
by blast consultants to predict blast loads. The overpressure is assumed to 
instantaneously rise to its peak value and decay linearly to zero in a time known as the 
duration time. In order to obtain the blast load, a number of different tools can be 
used. Tables of pre-determined values may be used (see GSA Security Reference Manual: 
Part 3  Blast Design & Assessment Guidelines, July 31, 2001) or computer programs may be 
used, such as: 1
_ ATBLAST (GSA)
_ CONWEP (U.S. Army Engineer Research and Development Center)
Figure 4-10 provides a quick method for predicting the expected overpressure 
(expressed in pounds per square inch or psi) on a building for a specific explosive 
weight and stand-off distance. Enter the x-axis with the estimated explosive weight a 
terrorist might use and the y-axis with a known stand-off distance from a building. By 
correlating the resultant effects of overpressure with other data, the degree of damage 
that the various components of a building might receive can be estimated. The 
vehicle icons in Figures 4-5 and 4-10 indicate the relative size of the vehicles that 
might be used to transport various quantities of explosives.
4.3.2 Blast Effects Predictions
After the blast load has been predicted, damage levels may be evaluated by explosive 
testing, engineering analysis, or both. Explosive testing is actively conducted by 
Federal Government agencies such as the Defense Threat Reduction Agency, DOS, 
and GSA. Manufacturers of innovative products also conduct explosive test programs 
to verify the effectiveness of their products. 
Often, testing is too expensive an option for the design community and an 
engineering analysis is performed instead. To accurately represent the response of an 
explosive event, the analysis needs to be time dependent and account for non-linear 
behavior.
Non-linear dynamic analysis techniques are similar to those currently used in 
advanced seismic analysis. Analytical models range from equivalent single-degree-of-
freedom (SDOF) models to finite element (FEM) representation. In either case, 
numerical computation requires adequate resolution in space and time to account 
for the high-intensity, short-duration loading and non-linear response. The main 
problems are the selection of the model, the appropriate failure modes, and, finally, 
the interpretation of the results for structural design details. Whenever possible, 
results are checked against data from tests and experiments on similar structures and 
loadings. Available computer programs include:
_ AT Planner (U.S. Army Engineer Research and Development Center)
_ BEEM (Technical Support Working Group)
_ BLASTFX (Federal Aviation Administration)
Components such as beams, slabs, or walls can often be modeled by a SDOF system. 
The response can be found by using the charts developed by Biggs and military 
handbooks. For more complex elements, the engineer must resort to numerical time 
integration techniques. The time and cost of the analysis cannot be ignored in 
choosing analytical procedures. SDOF models are suitable for numerical analysis on 
PCs and micro-computers, but the most sophisticated FEM systems (with non-linear 
material models and options for explicit modeling of reinforcing bars) may have to 
be carried out on mainframes. Because the design analysis process is a sequence of 
iteration, the cost of analysis must be justified in terms of benefits to the project and 
increased confidence in the reliability of the results. In some cases, an SDOF 
approach will be used for the preliminary design and a more sophisticated approach, 
using finite elements, will be used for the final design.
Table 4-3 provides estimates of incident pressures at which damage may occur.
Table 4-3: Damage Approximations

Damage
Incident Overpressure 
(psi)
Typical window glass breakage
0.15  0.22
Minor damage to some buildings
0.5  1.1
Panels of sheet metal buckled
1.1  1.8
Failure of concrete block walls
1.8  2.9
Collapse of wood framed buildings
Over 5.0
Serious damage to steel framed buildings
4  7
Severe damage to reinforced concrete 
structures
6  9
Probable total destruction of most buildings
10  12

SOURCE: EXPLOSIVE SHOCKS IN AIR, KINNEY & GRAHM, 1985; FACILITY DAMAGE AND PERSONNEL INJURY FROM 
EXPLOSIVE BLAST, MONTGOMERY & WARD, 1993; AND THE EFFECTS OF NUCLEAR WEAPONS, 3RD EDITION, GLASSTONE 
& DOLAN, 1977

Additional sources of information: 
_ Air Force Engineering and Services Center. Protective Construction Design Manual, ESL-
TR-87-57. Prepared for Engineering and Services Laboratory, Tyndall Air Force 
Base, FL. (1989).
_ U.S. Department of the Army. Fundamentals of Protective Design for Conventional Weapons, 
TM 5-855-1. Washington, DC, Headquarters, U.S. Department of the Army. (1986).
_ U.S. Department of the Army. Security Engineering, TM 5-853 and Air Force AFMAN 32-
1071, Volumes 1, 2, 3, and 4. Washington, DC, Departments of the Army and Air 
Force. (1994).
_ U.S. Department of the Army. Structures to Resist the Effects of Accidental Explosions, Army 
TM 5-1300, Navy NAVFAC P-397, AFR 88-2. Washington, DC, Departments of the 
Army, Navy, and Air Force. (1990).
_ U.S. Department of Energy. A Manual for the Prediction of Blast and Fragment Loading on 
Structures, DOE/TIC 11268. Washington, DC, Headquarters, U.S. Department of 
Energy. (1992).
_ U.S. General Services Administration. GSA Security Reference Manual: Part 3 Blast Design 
and Assessment Guidelines. (2001).
_ Biggs, John M. Introduction to Structural Dynamics. McGraw-Hill. (1964).
_ The Institute of Structural Engineers. The Structural Engineers Response to Explosive 
Damage. SETO, Ltd., 11 Upper Belgrave Street, London SW1X8BH. (1995).
_ Mays, G.S. and Smith, P.D. Blast Effects on Buildings: Design of Buildings to Optimize 
Resistance to Blast Loading. Thomas Telford Publications, 1 Heron Quay, London E14 
4JD. (1995).
_ National Research Council. Protecting Buildings from Bomb Damage. National Academy 
Press. (1995)


Figure 4-1 Typical pressure-time histor


Figure 4-2 Reflected pressure coefficient vs. angle of incidenc


The integrated area under the pressure verse time function is known as the impulse: 
 I = P(t)dt
 I = impulse (psi-ms or Mpa-ms)
 P = Pressure (psi or MPa)
 T = time (ms


Figure 4-3 Typical impulse wavefor


Figure 4-4 Blast pressure effects on a structur


SOURCE: NAVAL FACILITIES ENGINEERING SERVICE CENTER, USERS GUIDE ON PROTECTION AGAINST TERRORIST 
VEHICLE BOMBS, MAY 199


Table 4-1: DoD Minimum Antiterrorism (AT) Standards for New Buildings*

Level of 
Protection
Potential Structural Damage
Potential Door and Glazing 
Hazards
Potential Injury
Below AT 
standards
Severely damaged. Frame 
collapse/massive destruction. 
Little left standing. 
Doors and windows fail and 
result in lethal hazards 
Majority of 
personnel suffer 
fatalities. 
Very Low
Heavily damaged - onset of 
structural collapse. Major 
deformation of primary and 
secondary structural members, 
but progressive collapse is 
unlikely. Collapse of non-
structural elements. 
Glazing will break and is 
likely to be propelled into 
the building, resulting in 
serious glazing fragment 
injuries, but fragments will 
be reduced. Doors may be 
propelled into rooms, 
presenting serious hazards. 
Majority of 
personnel suffer 
serious injuries. 
There are likely to 
be a limited number 
(10 percent to 25 
percent) of fatalities. 
Low
Damaged  unrepairable. 
Major deformation of non-
structural elements and 
secondary structural members, 
and minor deformation of 
primary structural members, but 
progressive collapse is unlikely. 
Glazing will break, but fall 
within 1 meter of the wall or 
otherwise not present a 
significant fragment hazard. 
Doors may fail, but they will 
rebound out of their frames, 
presenting minimal hazards. 
Majority of 
personnel suffer 
significant injuries. 
There may be a few 
(<10 percent) 
fatalities. 
Medium
Damaged  repairable. 
Minor deformations of non-
structural elements and 
secondary structural members 
and no permanent deformation 
in primary structural members. 
Glazing will break, but will 
remain in the window frame. 
Doors will stay in frames, 
but will not be reusable. 
Some minor injuries, 
but fatalities are 
unlikely. 
High
Superficially damaged. 
No permanent deformation of 
primary and secondary structural 
members or non-structural 
elements. 
Glazing will not break. 
Doors will be reusable. 
Only superficial 
injuries are likely. 


* THE DoD UNIFIED FACILITIES CRITERIA (UFC), DoD MINIMUM ANTITERRORISM STANDARDS FOR BUILDINGS, UFC 4-010-
01 31 JULY 200


For design purposes, large-scale truck bombs typically contain 10,000 pounds or more of TNT 
equivalent, depending on the size and capacity of the vehicle used to deliver the weapon. Vehicle 
bombs that utilize vans down to small sedans typically contain 4,000 to 500 pounds of TNT 
equivalent, respectively. A briefcase bomb is approximately 50 pounds, and a pipe bomb is generally 
in the range of 5 pounds of TNT equivalent


SOURCE: DEFENSE THREAT REDUCTION AGENC


Figure 4-5 Explosives environments - blast range to effect


Figure 4- 6 Blast analysis of a building for a typical car bomb detonated in the buildings parking lot


Figure 4-7 Blast analysis of a building for a typical large truck bomb detonated in the buildings 
parking lot


SOURCE: U.S. AIR FORCE, INSTALLATION FORCE PROTECTION GUID


Figure 4-8 Relationship of cost to stand-off distanc


SOURCE: U.S. AIR FORCE, INSTALLATION FORCE PROTECTION GUID


Figure 4-9 Stand-off distance and its relationship to blast impact as modeled on the Khobar Towers 
sit


SOURCE: U.S. AIR FORCE, INSTALLATION FORCE PROTECTION GUID


Figure 4-10 Incident overpressure measured in pounds per square inch, as a function of stand-off 
distance and net explosive weight (pounds-TNT


 1For security reasons, the distribution of these computer programs is limited.




CHEMICAL, BIOLOGICAL, AND RADIOLOGICAL MEASURES     




This chapter is based on guidance from the CDC/NIOSH and the DoD and 
presents protective measures and actions to safeguard the occupants of a building 
from CBR threats. Evacuation, sheltering in place, personal protective equipment, air 
filtration and pressurization, and exhausting and purging will be discussed, as well as 
CBR detection1. Additionally, CBR design mitigation measures are discussed in 
Chapter 3 and Appendix C contains a glossary of CBR terms and a summary of CBR 
agent characteristics.
Recent terrorist events have increased interest in the vulnerability of buildings to 
CBR threats. Of particular concern are building HVAC systems, because they can 
become an entry point and distribution system for airborne hazardous contaminants. 
Even without special protective systems, buildings can provide protection in varying 
degrees against airborne hazards that originate outdoors. Conversely, the hazards 
produced by a release inside a building can be much more severe than a similar 
release outdoors. Because buildings allow only a limited exchange of air between 
indoors and outdoors, not only can higher concentrations occur when there is a 
release inside, but hazards may persist longer indoors.
After the presence of an airborne hazard is detected, there are five possible protective 
actions for a building and its occupants. In increasing order of complexity and cost, 
these actions are:
1. Evacuation
2. Sheltering in Place
3. Personal Protective Equipment
4. Air Filtration and Pressurization
5. Exhausting and Purging
These actions are implemented, singly or in combination, when a hazard is present 
or known to be imminent. To ensure these actions will be effective, a protective-
action plan specific to each building, as well as training and familiarization for 
occupants, is required. Exhausting and purging is listed last because it is usually the 
final action after any airborne hazard incident.
5.1 EVACUATION
Evacuation is the most common protective action taken when an airborne hazard, 
such as smoke or an unusual odor, is perceived in a building. In most cases, existing 
plans for fire evacuation apply. Orderly evacuation is the simplest and most reliable 
action for an internal airborne hazard. However, it may not be the best action in all 
situations, especially in the case of an external CBR release or plume, particularly one 
that is widespread. If the area covered by the plume is too large to rapidly and safely 
exit, sheltering in place should be considered. If a CBR agent has infiltrated the 
building and evacuation is deemed not to be safe, the use of protective hoods may be 
appropriate. Two considerations in non-fire evacuation are: 1) to determine if the 
source of the airborne hazard is internal or external, and 2) to determine if 
evacuation may lead to other risks. Also, evacuation and assembly of occupants 
should be on the upwind side of the building and at least 100 feet away, because any 
airborne hazard escaping the building will be carried downwind.
5.2 SHELTERING IN PLACE 
In normal operations, a building does little to protect occupants from airborne 
hazards outside the building because outdoor air must be continuously introduced to 
provide a comfortable, healthy indoor environment. However, a building can provide 
substantial protection against agents released outdoors if the flow of fresh air is 
filtered/cleaned, or temporarily interrupted or reduced. Interrupting the flow of fresh 
air is the principle applied in the protective action known as sheltering in place.
The advantage of sheltering in place is that it can be implemented rapidly. The 
disadvantage is that its protection is variable and diminishes with the duration of the 
hazard. Sheltering requires that two distinct actions be taken without delay to 
maximize the passive protection a building provides: 
_	First, reduce the indoor-outdoor air exchange rate before the hazardous plume 
arrives. This is achieved by closing all windows and doors, and turning off all fans, 
air conditioners, and combustion heaters.
_	Second, increase the indoor-outdoor air exchange rate as soon as the hazardous 
plume has passed. This is achieved by opening all windows and doors, and turning 
on all fans to ventilate the building. 
The level of protection that can be attained by sheltering in place is substantial, but it 
is less than can be provided by high efficiency filtration of the fresh air introduced 
into the building. The amount of protection varies with:
_		The buildings air exchange rate. The tighter the building (i.e., the lower the 
air exchange rate), the greater the protection it provides. In most cases, air 
conditioners and combustion heaters cannot be operated while sheltering in 
place because operating them increases the indoor-outdoor exchange of air. 
_		The duration of exposure. Protection varies with time, diminishing as the time 
of exposure increases. Sheltering in place is, therefore, suitable only for exposures 
of short duration, roughly 2 hours or less, depending on conditions. 
_		Purging or period of occupancy. How long occupants remain in the building 
after the hazardous plume has passed also affects the level of protection. Because 
the building slowly purges contaminants that have entered it, at some point 
during plume passage, the concentration inside exceeds the concentration 
outside. Maximum protection is attained by increasing the air exchange rate after 
plume passage or by exiting the building into clean air. 
_		Natural filtering. Some filtering occurs when the agent is deposited in the 
building shell or upon interior surfaces as air passes into and out of the building. 
The tighter the building, the greater the effect of this natural filtering. 
In a home, taking the actions required for sheltering (i.e., closing windows and 
doors, and turning off all air conditioners, fans, and combustion heaters) is relatively 
simple. Doing so in a commercial or apartment building may require more time and 
planning. All air handling units must be turned off and any dampers for outside air 
must be closed. Procedures for a protective action plan, therefore, should include:
_	Identifying all air handling units, fans, and the switches needed to deactivate 
them.
_	Identifying cracks, seams, joints, and pores in the building envelope to be 
temporarily sealed to further reduce outside air infiltration. Keeping emergency 
supplies, such as duct tape and polyethylene sheeting, on hand.
_	Identifying procedures for purging after an internal release (i.e., opening windows 
and doors, turning on smoke fans, air handlers, and fans that were turned off) to 
exhaust and purge the building. 
_	Identifying sheltering rooms (i.e., interior rooms having a lower air exchange 
rate) that may provide a higher level of passive protection. It may be desirable to go 
to a predetermined sheltering room (or rooms) and:
   Shut and lock all windows and doors
   Seal any windows and vents with plastic sheeting and duct tape
   Seal the door(s) with duct tape around the top, bottom, and sides
   Firmly pack dampened towels along the bottom of each door
   Turn on a TV or radio that can be heard within the shelter and listen for 
further instructions
   When the "all clear" is announced, open windows and doors
Important considerations for use of sheltering in place are that stairwells must be 
isolated by closed fire doors, elevators must not be used, and clear evacuation routes 
must remain open if evacuation is required. Escape hoods may be needed if the only 
evacuation routes are through contaminated areas. 
One final consideration for sheltering in place is that occupants cannot be forced to 
participate. It is important to develop a plan in cooperation with likely participants 
and awareness training programs that include discussions of sheltering in place and 
events (CBR attacks, hazardous material releases, or natural disasters) that might 
make sheltering preferable to evacuation. During an event, some building protective 
action plans call for making a concise information announcement, and then giving 
occupants 3 to 5 minutes to proceed to the sheltering area or evacuate the building 
before it is sealed. Training programs and information announcements during an 
event should be tailored to help occupants to make informed decisions.
5.3 PERSONAL PROTECTIVE EQUIPMENT
A wide range of individual protection equipment is available, including respirators, 
protective hoods, protective suits, CBR detectors, decontamination equipment, etc. 
The DOJ, National Institute of Justice (NIJ), Guide for the Selection of Personal Protective 
Equipment for Emergency First Responders (NIJ Guide 102-00, Volumes I-IV) provides 
summarizes and evaluates a wide range of personal protective equipment. The U.S. 
Joint Service Materiel Group (JSMG) has sponsored the Nuclear Biological Chemical 
(NBC) Industry Group to produce a catalogue of CBR products and services 
manufactured and provided by companies in the United States. 
Of particular note, new models of universal-fit escape hoods have been developed for 
short-duration "escape-only" wear to protect against chemical agents, aerosols 
(including biological agents), and some toxic industrial chemicals. These hoods are 
compact enough to be stored in desks or to be carried on the belt. They should be 
stored in their sealed pouches and opened only when needed. Most of these hoods 
form protective seals at the neck and do not require special fitting techniques or 
multiple sizes to fit a large portion of the population. Training is required to use the 
hoods properly. Depending on hood design, the wearer must breathe through a 
mouth bit or use straps to tighten a nose cup around the nose and mouth (see Figure 
5-1). 
The protective capability and shelf life of these hoods varies with the design. The 
filters of the hoods contain both high efficiency particulate air (HEPA) filters and 
packed carbon beds, so they will remove chemical and biological aerosols, as well as 
chemical vapors and gases. Although the carbon filters are designed to filter a broad 
range of toxic chemicals, they cannot filter all chemicals. An important 
consideration in planning for use of escape hoods is that their filters are not effective 
against certain chemicals of high vapor pressure. Chemical masks provide no 
protection against carbon monoxide, which is produced in fires. Manufacturers data 
should be checked closely when ordering. Other escape hoods are available that 
employ compressed oxygen cylinders, rather than air filters, to provide eye and 
respiratory protection for very short periods. 
There are no government standards for hoods intended for protection against the 
malicious use of chemical or biological agents. In selecting an escape hood, a 
purchaser should, therefore, require information on laboratory verification testing. 
Plans should be made for training, fitting, storing, and maintaining records relative 
to storage life, and there should be procedures for instructing building occupants as 
to when to put on the hoods. Wearing a mask can cause physiological strain and may 
cause panic or stress that could lead to respiratory problems in some people. Finally, 
it should be recognized that no single selection of personal protective equipment is 
effective against every possible threat. Selection must be tied to specific threat/hazard 
characteristics.
5.4 AIR FILTRATION AND PRESSURIZATION
Among the various protective measures for buildings, high efficiency air 
filtration/cleaning provides the highest level of protection against an outdoor 
release of hazardous materials. It can also provide continuous protection, unlike 
other approaches for which protective measures are initiated upon detecting an 
airborne hazard. 
Two basic methods of applying air filtration to a building are external filtration and 
internal filtration. External filtration involves drawing air from outside, filtering 
and/or cleaning it, and discharging the air inside the building or protected zone. 
This provides the higher level of protection, but involves substantially higher costs. 
Internal filtration involves drawing air from inside the building, filtering and/or 
cleaning it, and discharging the air back inside the building. 
The relative levels of protection of the two methods can be illustrated in terms of 
protection factor, and the ratio of external dose and internal dose (concentration 
integrated over time). External filtration systems with high efficiency filters can yield 
protection factors greater than 100,000. For internal filtration, the protection factors 
are likely to be less and are highly variable. The protection of internal filtration varies 
with a number of factors, including those listed in sheltering in place, the efficiency 
of the filter, flow rate of the filter unit, and size of the room or building in which the 
filter unit operates. 
5.4.1 Air Filtration and Cleaning Principles
Air filtration is the removal of particulate contaminants from the air. Air cleaning is 
the removal of gases or vapors from the air. The collection mechanisms for these two 
types of systems are very different.
Particulate Air Filters. Particulate air filters consist of fibrous materials (see Figure 5-
2), which capture aerosols. Their efficiency will depend on the size of the aerosol, the 
type of filter, the velocity of the air, and the type of microbe. The basic principle of 
particulate air filtration is not to restrict the passage of particles by the gap between 
fibers, but by altering the airflow streamlines. The airflow will slip around the fiber, 
but higher density aerosols and particulates will not change direction as rapidly. 
Four different collection mechanisms govern particulate air filter performance: iner-
tial impaction, interception, diffusion, and electrostatic attraction (see Figure 5-3). 
The first three mechanisms are the most important for mechanical filters and are 
influenced by particle size. Impaction occurs when a particle in an air stream passing 
around a filter fiber, because of its inertia, deviates from the air stream and collides 
with a fiber. Interception occurs when a particle in the air stream passing around 
filter fibers comes in contact with a fiber because of its size. Impaction and 
interception are dominant for large particles (> 0.2 microns). Diffusion occurs when 
the random (Brownian) motion of a particle causes that particle to contact a fiber. 
Diffusion is the dominant collection mechanism for smaller particles (< 0.2 
microns). The combined effect of these three collection mechanisms results in the 
classic collection efficiency curve that is shown in Figure 5-4. The fourth mechanism, 
electrostatic attraction, plays a minor role in mechanical filtration because, after 
fiber contact is made, small particles are retained on the fibers by a weak electrostatic 
force. 
Electrostatically enhanced filters are different from electrostatic precipitators, also 
known as electronic air cleaners. Electrostatic precipitators require electrical power 
and charged plates to attract and capture particles. In electrostatic filters, the elec-
trostatically enhanced fibers actually attract the particles to the fibers, in addition to 
retaining them. Electrostatic filters use polarized fibers to increase the collection 
efficiency, typically have less packing density, and consequently will have a much 
lower pressure drop than a similar efficiency mechanical filter. 
Particulate air filters are classified as mechanical filters or electrostatic filters. As a 
mechanical filter loads with particles over time, its collection efficiency and pressure 
drop typically increase. The pressure drop caused by particulate air filters must be 
taken into account in HVAC system design. Higher capacity fan units may be needed 
to overcome increased resistance caused by higher efficiency filters. Eventually, the 
increased pressure drop significantly inhibits airflow, and the filters must be 
replaced. For this reason, pressure drop across mechanical filters is often monitored 
because it indicates when to replace filters. Conversely, electrostatic filters may lose 
their collection efficiency over time when exposed to certain chemicals, aerosols, or 
high relative humidities. Pressure drop in an electrostatic filter generally increases at 
a slower rate than it does in a mechanical filter of similar efficiency. Thus, unlike the 
mechanical filter, pressure drop for the electrostatic filter is a poor indicator of the 
need to change filters. Periodic aerosol measurements may be appropriate to verify 
their performance. When selecting an HVAC filter, the differences between 
mechanical and electrostatic filters will have an impact on the filters performance 
(collection efficiency over time), as well as on maintenance requirements (change-
out schedules).
Particulate air filters are commonly rated based on their collection efficiency, 
pressure drop (airflow resistance), and particulate holding capacity. Two filter-rating 
systems are currently used in the United States, the American Society of Heating, Re-
frigerating, and Air-conditioning Engineers (ASHRAE) Standard 52.1-1992 and 
ASHRAE Standard 52.2-1999. Standard 52.1 measures arrestance, dust spot efficiency, 
and dust holding capacity. Arrestance refers to a filters ability to capture a mass 
fraction of coarse test dust and is better suited for describing low- and medium-
efficiency filters. Dust spot efficiency measures a filters ability to remove particles 
that tend to soil the interior of buildings. Arrestance values may be high even for low 
efficiency filters, and may not adequately differentiate the effectiveness of different 
filters for CBR protection. Dust holding capacity is a measure of the total amount of 
dust a filter is able to hold during a dust-loading test.
ASHRAE Standard 52.2 measures particle size efficiency (PSE). This newer standard is 
a more descriptive test, which quantifies filtration efficiency in different particle size 
ranges and is more applicable in determining a filters effectiveness to capture a 
specific agent. Standard 52.2 reports the particle size efficiency results as a minimum 
efficiency reporting value (MERV) rating between 1 and 20. A higher MERV rating 
indicates a more efficient filter. The standard provides a table (see Table 5-1) showing 
minimum PSE for three size ranges for each of the MERV numbers 1 through 16. 
Thus, if the size of a contaminant is known, an appropriate filter with the desired PSE 
for that particular particle size can be identified.
A wide variety of particulate air filters are available to meet many specialized needs. 
They range from the low efficiency dust filters, such as roll-type filters used in 
commercial buildings, to HEPA and ultra low penetration air (ULPA) filters used in 
clean rooms and operating rooms (see Figure 5-5). 
HEPA filters are typically rated as 99.97 percent effective in removing dust and 
particulate matter greater than 0.3 micron in size. The performance of high 
efficiency ASHRE filters is defined in terms of their total arrestance. Graphs of filter 
efficiency versus particle size do not constitute performance requirements and are 
merely a convenient way of describing performance (see Figure 5-6). Filters with the 
same total arrestance may have different performance curves. 
Figure 5-7 is the characteristic performance curve of a typical HEPA filter with the 
design point indicated. The dip between 0.1 and 0.3 microns represents the most 
penetrating particle size. Many bacteria and viruses fall into this size range. 
Fortunately, microbes in this range are also vulnerable to ultraviolet radiation. For 
this reason, many health care facilities couple particulate air filters with ultraviolet 
germicidal irradiation (UVGI). UVGI will be discussed later in this section. 
Sorbent Filters. Particulate filters are not intended to remove gases and vapors. 
Sorbent filters use one of two mechanisms for capturing and controlling gas-phase 
air contaminants, physical absorption or chemisorption. 
Both mechanisms remove specific types of gas-phase contaminants in indoor air. 
Unlike particulate filters, sorbents cover a wide range of highly porous materials (see 
Figure 5-8), ranging from simple clays and carbons to complex engineered polymers. 
Many sorbents, with the exception of those that are chemically active, can be 
regenerated by application of heat or other processes. 
Understanding the precise removal mechanism for gases and vapors is often difficult 
due to the nature of the adsorbent and the processes involved. Although knowledge 
of adsorption equilibrium helps in understanding vapor protection, filter per-
formance depends on such properties as mass transfer, chemical reaction rates, and 
chemical reaction capacity. Some of the most important parameters include the 
following:
_ Breakthrough concentration. Breakthrough concentration is the downstream 
contaminant concentration, above which the sorbent is considered to be 
performing inadequately. Its concentration indicates the agent has broken 
through the sorbent, which is no longer providing maximum protection. This 
parameter is a function of loading history, relative humidity, and other factors.
_ Breakthrough time. Breakthrough time is the elapsed time between initial contact 
of the toxic agent, at a reported challenge concentration, with the upstream 
surface of the sorbent bed and the time at which the breakthrough concentration 
occurs on the downstream side of the sorbent bed.
_ Challenge concentration. Challenge concentration is the airborne concentration of 
the hazardous agent entering the sorbent. 
_ Residence time. Residence time is the length of time that the hazardous agent 
spends in contact with the sorbent. This term is generally used in the context of 
superficial residence time, which is calculated on the basis of the adsorbent bed 
volume and the volumetric flow rate.
_ Mass transfer zone or critical bed depth. Mass transfer zone or critical bed depth are 
interchangeably used terms. They refer to the adsorbent bed depth required to 
reduce the chemical vapor challenge to the breakthrough concentration. When 
applied to the challenge chemicals that are removed by chemical reaction, mass 
transfer is not as precise a descriptor, but is often used in that context. The 
portion of the adsorbent bed not included in the mass transfer zone is often 
termed the capacity zone.
Choosing the appropriate sorbent or sorbents for an airborne contaminant is a 
complex decision that involves many factors. The installation of sorbent filters for 
the removal of gaseous contaminants from a buildings air is a less common practice 
than the installation of particulate filtration. Sorbents have different affinities, 
removal efficiencies, and saturation points for each chemical agent. The EPA states 
that a well-designed adsorption system should have removal efficiencies ranging 
from 95 percent to 98 percent for industrial contaminant concentrations in the range 
of 500 to 2,000 ppm; higher collection efficiencies are needed for high toxicity CBR 
agents. Sorbent physicochemical properties (e.g., pore size and shape, surface area, 
pore volume, and chemical inertness) all influence the ability of a sorbent to collect 
gases and vapors. Sorbent manufacturers have published extensive information 
regarding the proper use of gas-phase sorbents, based upon contaminants and 
conditions. The air contaminants concentration, molecular weight, molecule size, 
and temperature are all important.
Sorbents are rated in terms of adsorption capacity (i.e., the amount of the chemical 
that can be captured) for many chemicals. This capacity rises as concentration 
increases and temperature decreases. The rate of adsorption (i.e., the efficiency) falls 
as the amount of contaminant captured grows. Adsorption capacity information 
(available from manufacturers, scientific literature, and the Internet) allows users to 
predict the service life of a sorbent bed. 
Gases are removed in the sorbent beds mass transfer zone. As the sorbent bed 
removes gases and vapors, the leading edge of this zone is saturated with the 
contaminant, while the trailing edge is clean, as dictated by the adsorption capacity, 
exposure history, and filtration dynamics. Significant quantities of the air 
contaminant may pass through the sorbent bed if breakthrough occurs. Break-
through may be avoided by selecting the appropriate quantity of sorbent and 
performing regular maintenance.
Activated carbon (see Figure 5-9) is the most common sorbent. The huge surface area 
of activated carbon gives it countless bonding sites. Typically, the pores in highly 
activated carbon have a total surface area of over 1,000 square meters per gram. 
Common substances used as a base material for producing carbon are wood, coal, 
and coconut shell. Impregnating carbon with special chemicals can enhance the 
absorption of specific gases. A broad-based chemical addition typically used is copper-
silver-zinc-molybdenum-triethylenediamine (ASZM-TEDA). Both the DOS and DoD 
currently recommend ASZM-TEDA sorbent for collecting classical chemical warfare 
agents.
Sorbent filters should be located downstream of the particulate filters. This 
arrangement allows the sorbent to collect vapors generated from liquid aerosols 
collected on the particulate filter and reduces the amount of particulate reaching the 
sorbent. Gas-phase contaminant removal can potentially be a challenging and costly 
undertaking, and different factors should be addressed. 
All sorbents have limited adsorption capacities and require scheduled maintenance. 
The effective residual capacity of an activated carbon sorbent bed is not easily 
determined while in use, and saturated sorbents can re-emit collected contaminants. 
Sorbent life depends upon bed volume or mass, along with shape, which influences 
airflow through the sorbent bed. Chemical agent concentrations and other gases 
(including humidity) affect the bed capacity. Because of differences in affinities, it is 
possible that one chemical may displace another chemical, which can be re-adsorbed 
downstream or forced out of the bed. Most sorbents come in pellet form, which 
makes it possible to mix them. Mixed- and/or layered-sorbent beds permit effective 
removal of a broader range of contaminants than possible with a single sorbent. 
Many sorbents can be regenerated, and it is important to closely follow 
manufacturers guidance to ensure that sorbents are replaced or regenerated in a safe 
and effective manner.
Some chemically active sorbents are impregnated with strong oxidizers, such as 
potassium permanganate. The adsorbent part of the bed captures the target gas and 
gives the oxidizer time to react and destroy other agents. Chemically active sorbents 
should not be reused because the oxidizer is consumed over time. If the adsorbent 
bed is exposed to high concentrations of vapors, exothermic adsorption could lead to 
a large temperature rise and filter bed ignition. This risk can be exacerbated by the 
nature of impregnation materials. It is well known that lead and other metals can 
significantly lower the spontaneous ignition temperature of a carbon filter bed. 
Sorbent bed fires are extremely dangerous, and steps should be taken to avoid this 
hazard. These systems should be located away from heat sources and automatic shut-
off and warning capabilities should be included in the system.
Air Filtration Considerations. In addition to proper filter or sorbent selection, the 
following must be considered when installing or upgrading filtration systems:
_ Filter bypass is a common problem found in many HVAC filtration systems. It 
occurs when air, rather than moving through the filter, goes around it, decreasing 
collection efficiency and defeating the intended purpose of the filtration system. 
Filter bypass is often caused by poorly fitting filters, poor sealing of filters in their 
framing systems, missing filter panels, or leaks and openings in the air handling 
unit downstream of the filter bank and upstream of the blower. Simply improving 
filter efficiency without addressing filter bypass provides little, if any, improvement 
to system efficiency.
_ Cost is another issue affected by HVAC filtration systems. Both first and life-cycle 
costs should be considered (e.g., initial installation, replacement, operating, 
maintenance, etc.). Not only are higher-efficiency filters and sorbent filters more 
expensive than the filters traditionally used in HVAC systems, but fan units may 
also need to be upgraded to handle the increased pressure drop associated with 
the upgraded filtration systems. Although improved filtration will normally come 
at a higher cost, many of these costs can be partially offset by the beneficial effects, 
such as cleaner (and more efficient) HVAC components and improved indoor 
environmental quality.
_ Filtration and air-cleaning affect only the air that passes through the filtration and 
air-cleaning device, whether it is outdoor air, recirculated air, or a mixture of the 
two. Building envelopes in residential and commercial buildings are, in general, 
quite leaky, and significant quantities of air can infiltrate the building envelope 
with minimal filtration. Field studies have shown that, unless specific measures 
are taken to reduce infiltration, as much air may enter a building through 
infiltration as through the mechanical ventilation system. Therefore, building 
managers should not expect filtration alone to protect a building from outdoor 
releases, particularly for systems in which no make-up air or inadequate over-
pressure is present. Instead, filtration in combination with other steps, such as 
building pressurization and tightening the building envelope, should be 
considered to increase the likelihood that the air entering the building actually 
passes through the filtration and air-cleaning systems.
Ultraviolet Germicidal Irradiation (UVGI). UVGI has long been used in laboratories 
and health care facilities. Ultraviolet radiation in the range of 2,250-3,020 Angstroms 
is lethal to microorganisms. All viruses and almost all bacteria (excluding spores) are 
vulnerable to moderate levels of UVGI exposure. Spores, which are larger and more 
resistant to UVGI than most bacteria, can be effectively removed through high 
efficiency air filtration. For these reasons, today most UGVI systems are installed in 
conjunction with high efficiency filtration systems in many health care facilities. 
Ultraviolet (UV) lamps resemble ordinary fluorescent lamps (see Figure 5-10), but are 
specially designed to emit germicidal UV and include a glass envelope to filter out 
harmful, ozone forming radiation. The lamps are available in a variety of sizes and 
shapes and must be mounted in special housings and located so that people are not 
exposed to direct irradiation. Newer more advanced compact UV tubes provide 
higher output in the UV-C bandwidth (253.7 nanometer wavelength) and increased 
reliability. UVGI safety measures, such as duct access interlocks that turn off the 
lamps when the duct housing is opened, should be used. 
Manufacturers offer UVGI systems suitable for in-duct or large plenum installations. 
Retrofitting UVGI systems can also be relatively simple if sufficient space is available. 
There are UV lamps that can be mounted externally in ductwork and pressure losses 
across such lamps are often negligible. When installing a UVGI system, attention 
must be paid to maintaining design air velocity and temperature of the UV lamps. 
Cooling the plasma inside a UV lamp can significantly affect its UV output. Polished 
aluminum reflective panels can also be used to increase the intensity of a UVGI field 
in an enclosed duct or chamber. The design velocity for a typical UVGI unit is similar 
to that of particulate filters (about 400 feet per minute). It is very important to 
properly design and install UVGI systems in order to obtain the desired effects. 
Improper systems may provide a false sense of protection. For a discussion of the 
factors that should be considered when designing and sizing a UVGI system, 
additional information can be found in W. J. Kowalski, Immune Building Systems 
Technology (McGraw Hill, 2003).
A design utilizing a combination of filtration and UVGI can be very effective against 
biological agents. Smaller microbes, which are difficult to filter out, tend to be more 
susceptible to UVGI; while larger microbes, such as spores, which are more resistant 
to UVGI, tend to be easier to filter out. 
5.4.2 Applying External Filtration 
Applying external filtration to a building requires modifications to the buildings 
HVAC system and electrical system, and it also usually requires minor architectural 
changes to reduce air leakage from the selected protective envelope. These changes 
are necessary to ensure that, when the protective system is in operation, all outside air 
enters the building through the filters. The air exchange that normally occurs due to 
wind, chimney effect, and operation of fans must be reduced to zero. This is achieved 
mainly by introducing filtered air at a rate sufficient to produce an overpressure in 
the building and create an outward flow through all cracks, pores, seams, and other 
openings in the building envelope. For standby systems, dampers are normally 
required to tighten the envelope in transitioning to the protective mode. The level of 
overpressure required varies with weather conditions and height of the building. 
The capacity of filtration units needed for protection is determined by the leakage 
characteristics and size of the building. The cost of installing a high efficiency 
filtration system varies directly with the leakage rate; higher leakage rate equals 
higher costs, and the need for additional heating and cooling capacity for the 
filtered air. 
Filtration system capacity must be matched to the leakage of the building to achieve 
maximum protection. Fan-pressurization tests are usually performed on buildings to 
determine their normalized leakage rates. Nominal data on the leakage rates of 
various types of buildings are available in the U.S. Army Corps of Engineers 
Engineering Technical Letter (ETL) 1110-3-498, Design of Collective Protection Shelters to 
Resist Chemical, Biological, and Radiological (CBR) Agents, (February 24, 1999) and can be 
used to estimate the leakage rate of a building.  
For a terrorist threat, the U.S. Army Corps of Engineers recommends a minimum 
HVAC CBR filtration system overpressure goal of 5 Pa (0.02 inch water gauge [wg]). 
This overpressure corresponds to an impact pressure normal to a wall from a 12-
km/hr (7-mph) wind. After installation of an overpressure system (see Figure 5-11), it 
is possible that a pressure greater than 5 Pa (0.02 inch wg) will be achieved. A higher 
pressure provides a higher factor of safety and should not be intentionally lowered.
Currently, there are no criteria or guidance for the performance of filtration systems 
designed for protecting building occupants against CBR agents. The U.S. military has 
issued very conservative criteria in the ETL referenced above, which is not based on 
analytical or empirical research. Recent research in the field suggests significant 
levels of protection can be achieved with medium to high efficiency filters (see Figure 
5-12), especially when used in combination with UVGI.1 In a recent simulation in the 
Architectural Engineering Department of Pennsylvania State University, various 
combinations of MERV and UVGI Rating Values (URV) systems were modeled for a 
20-story building subject to releases of anthrax, smallpox, and botulinum. No 
significant benefits were shown for filtration/URV levels beyond MERV 13/URV 13.2
Various types of high efficiency filter systems, both commercial and military, have 
been used for building protection. The current DoD recommended carbon for 
filtering a broad range of toxic chemical vapors and gases is ASZM-TEDA carbon per 
military specification EA-C-1704A maintained by the U.S. Army Edgewood Chemical 
Biological Center, Aberdeen Proving Ground, MD. 
High efficiency air filtration can be most economically applied by integrating it into 
the HVAC system in the design of new construction. Application of filtration systems 
in retrofit involves greater costs.
Filter systems can be applied to protect either all or part of a building. At least part of 
the building is always excluded from the envelope being protected (i.e., areas having 
or requiring high rates of air exchange with the outdoors, such as mechanical rooms 
containing boilers or generators and receiving areas). Mechanical rooms that 
contain air handling units must be included within the protective envelope. Filter 
systems may be designed to operate on either a continuous duty cycle or on standby. 
The assumption with the latter is that they will be turned on when there is greater 
likelihood of an airborne hazard occurring. 
The disadvantage of external air filtration is its high costs for hardware, installation, 
operation, and maintenance. The main cost component of operating the filter units 
is the electrical power required to force air through the filters. The airflow resistance 
of HEPA filters is typically about 1 inch wg, and this resistance increases steadily as 
the filter loads with dust or other fine particles in service. For high efficiency carbon 
filters, the pressure drop may range from about 1 to 4 inch wg. Maintenance costs 
involve periodic filter replacement. Particulate filter change-out is generally based on 
the airflow resistance rising to unacceptable levels.
There is no simple means for determining how much capacity remains in a carbon 
filter. Because the service life varies with the environment in which it operates, it can 
be replaced according to time in service using a conservative estimate, or its 
remaining capacity can be measured by the use of test canisters. With the reserve 
capacity normally designed into carbon filters, a filter can maintain efficiency greater 
than 99.999 percent for about 3 years of continuous use with ASZM-TEDA carbon, 
depending upon the quality of air in the environment it operates. 
5.4.3 Applying Internal Filtration (Recirculation Filter Units) 
Internal filtration can be applied much more easily, in many cases without any 
modifications to the building or installation costs; however, it provides a much lower 
level of protection against an external release than does high efficiency external 
filtration. One advantage of internal filtration is in purging contaminants from a 
building following an internal release. Also referred to as recirculation filtering, the 
protection it provides against an external release is dependent upon the rate at which 
air in the building envelope is exchanged with outdoor air. The tighter the building, 
the greater the protection achieved with internal filtration.
Recirculation filter units can be employed to increase protection achieved by 
sheltering in place. This involves the use of free-standing units referred to as indoor 
air purifiers or indoor air quality filter units. Many of these contain filters for removal 
of both aerosols and chemicals vapors. These typically have high efficiency filters for 
the removing aerosols (HEPA filters); however, the chemical filters are of relatively 
low efficiency, typically ranging from less than 50 percent to as high as 99 percent. 
Because of the relatively high efficiency of the HEPA filter versus the carbon filter, 
typically available in recirculation filter units, these units can provide a higher level 
of protection against an aerosol than against chemical vapors. The carbon filters also 
do not typically contain the impregnated carbon capable of removing chemicals of 
high vapor pressure. Manufacturers provide guidance on the size of room a single 
unit will accommodate. Because these filters are designed mainly for filtering pollen 
and dust and removing odors, there are no claims or guidance as to their protective 
capability. 
Internal filtration can also be applied by simply installing higher efficiency 
particulate filters and/or carbon filters in place of standard dust filters in air 
handling units. Air handling units are not designed, however, to accommodate the 
large increase in airflow resistance a high efficiency filter or carbon filter would add. 
The capability of the existing air handling unit must be examined before such 
installations are attempted. In typical air handling units, dust filter slots allow 
relatively high bypass around the filter media, reducing overall efficiency of the 
HEPA filters. Internal filtration protection against biological agents can also be 
enhanced through the installation of an UVGI system as discussed earlier. 
5.4.4 Radiological Hazards
Radiological hazards can be divided into three general forms: alpha, beta, and 
gamma radiation, which are emitted by radioisotopes that may occur as an aerosol, be 
carried on particulate matter, or occur in a gaseous state. Alpha particles, consisting 
of two neutrons and two protons, are the least penetrating and the most ionizing 
form of radiation. They are emitted from the nucleus of radioactive atoms and 
transfer their energy at very short distances. Alpha particles are readily shielded by 
paper or skin and are most dangerous when inhaled and deposited in the respiratory 
tract. Beta particles are negatively charged particles emitted from the nucleus of 
radioactive atoms. Beta particles are more penetrating than alpha particles, 
presenting an internal exposure hazard. They can penetrate the skin and cause 
burns. If they contact a high density material, they may generate x-rays also known as 
"Bremmstrahlung radiation." Gamma particles are emitted from the nucleus of an 
atom during radioactive decay. Gamma radiation can cause ionization in materials 
and biological damage to human tissues, presenting an external radiation hazard. 
There are three primary scenarios in which radioactive materials could be dispersed 
by a terrorist: use of conventional explosives or other means to spread radioactive 
materials (a dirty bomb), attack on a fixed nuclear facility, and use of a nuclear 
weapon. In any of these events, filtration and air cleaning devices would be ineffective 
at stopping the radiation itself; however, they would be useful in collecting the 
material from which the radiation is emitted. Micrometer-sized aerosols from a 
radiological event are effectively removed from air streams by HEPA filters. This 
collection could prevent distribution throughout a building; however, decontami-
nation of the HVAC system would be required.
5.5 EXHAUSTING AND PURGING
Turning on building ventilation fans and smoke-purge fans is a protective action for 
purging airborne hazards from the building and reducing occupant exposure, but it 
is mainly useful when the source of the hazard is indoors. 
Purging must be carefully applied with regard to the location of the source and the 
time of the release. It must be clear that the source of the hazard is inside the 
building and, if not, purging should not be attempted. If the hazardous material has 
been identified before release or immediately upon release, purging should not be 
employed, because it may spread the hazardous material throughout the building or 
HVAC zone. In this case, all air handling units should be turned off to isolate the 
hazard while evacuating or temporarily sheltering in place. 
Additionally, the ventilation system and smoke purge fans can be used to purge the 
building following an external release after the hazard outdoors has dissipated, and it 
has been confirmed that the agent is no longer present near the building. 
5.6 CBR DETECTION
Most strategies for protecting people from airborne hazards require a means of 
detection (i.e., determining that a hazard exists). Although effective and inexpensive 
devices are widely available to detect, for example, smoke and carbon monoxide, there 
are no detectors that can rapidly alert occupants to a broad range of chemical and 
biological hazards.
Chemical detection technology has improved vastly since Operation Desert Storm, 
where many military detection systems experienced high false alarm rates, but 
biological detection technology has not matured as fast. Biological signatures are not 
as distinctive as chemical signatures and can take 30 minutes or more to detect. 
Biological detection systems are expensive and generally require trained specialists to 
operate. Current chemical detectors work in approximately 10 seconds; however, the 
current state of biological and chemical detection is limited to detecting specific 
agents. There currently is no all-inclusive detection system available. Wide varieties of 
efficient radiological detectors have been developed for the nuclear industry and are 
commercially available. The NBC Products and Services Handbook, which was 
discussed in Section 5.3, contains a catalogue of CBR detection equipment. 
Additionally, the NIJ has reviewed chemical and biological detection devices in NIJ 
Guide 100-00: Guide for the selection of Chemical Agent and Toxic Industrial Material Detection 
Equipment for Emergency First Responders, June 2000; and NIJ Guide 101-00: An Introduction to 
Biological Agent Detection Equipment for Emergency First Responders, December 2001. 
Chemical Detectors. Driven largely by a desire to protect workers from toxic vapors in 
industrial environments, considerable information is known on the toxicity of 
chemical warfare agents, which often have dual uses in industry. A variety of detection 
technologies exist, ranging from inexpensive manual point detection devices (e.g., 
paper strips and calorimetric tubes) utilizing basic chemical reactions to trigger 
color changes, to sophisticated detection systems utilizing advanced technologies.
Chemical agents do not possess universal properties that permit detection by any 
single method. Therefore, most chemical detectors are designed to detect specific 
agents or a group of related agents. Most broad range detection systems actually 
combine several different sensors utilizing different technologies and can be very 
expensive and complex. Nevertheless, today there are numerous commercially 
available chemical detectors. The most capable detectors utilize ion mobility 
spectrometry (IMS), surface acoustic wave (SAW), or gas chromatograph/mass 
spectrometer (GC/MS) technologies to detect chemical agents and toxic industrial 
materials (TIMs).
IMS detectors draw gaseous samples with an air pump into a reaction chamber where 
a radioactive source ionizes the sample. The ionized sample is then injected into a 
closed drift tube through a shutter that isolates the sample from atmospheric air. The 
drift tube has a weak electric field that draws the sample toward an ion detector. An 
electrical charge is generated upon impact with the ion detector. The time it takes for 
species to traverse the field and the intensity of the charge generated are used as a 
means of identifying the chemical agent. 
SAW detectors consist of piezoelectric crystals coated with a film specially designed to 
absorb chemical agents from the air. They typically use multiple piezoelectric crystals 
coated with different polymeric films, each designed to absorb a particular class of 
volatile compound. The piezoelectric crystals absorb chemical vapors, which cause 
the resonant frequency of the crystal to change. By monitoring the resonant 
frequency of the different piezoelectric crystals, a response pattern of the system for a 
particular vapor is generated. Many SAW devices use pre-concentration tubes to re-
duce environmental interferences and increase detector sensitivity.
A GC uses inert gas to transport a sample of air through a long chromatographic 
column. Each molecule sticks to the column with a different amount of force and 
does not travel down the column at the same speed as the carrier gas. This causes the 
chemical agents and interferants to come out of the end of the column at different 
times (called the retention time). Because the retention time is known for the 
chemical agents, the signal from an associated detector is only observed for a short 
period starting before and ending just after the retention time of the chemical agent, 
eliminating false alarms from similar compounds that have different retention times. 
Using a pre-concentrator specific to the analyte can also reduce false alarms caused 
by interferants.
Mass spectrometry is a technique that can positively identify a chemical agent at very 
low concentrations. In this technique, a volatilized sample is ionized, typically by an 
electron beam, which also causes the molecule to fragment into smaller ionized 
pieces. The ionized molecules and fragments are then passed into a mass analyzer 
that uses electric fields to separate the ions according to the ratio of their mass 
divided by their electric charge. The analyzer allows only ions of the same mass over 
charge ratio to impinge upon the detector. By scanning the electric potentials in the 
mass analyzer, all the different mass/charge ions can be detected. The result is a mass 
spectrum that shows the relative amount and the mass of each fragment, and the 
unfragmented parent molecule. Because each molecule forms a unique set of 
fragments, mass spectroscopy provides positive identification. To simplify in-
terpretation of the mass spectrum, it is best to introduce only one compound at a 
time. This is often achieved by using a gas chromatograph to separate the 
components in the sample. The end of the gas chromatography column is connected 
directly to the inlet of the mass spectrometer. When used in combination, a GC/MS is 
one of the most sensitive and discerning tools for identifying chemical and 
biological compounds; however, it requires significant skill to operate and interpret 
the results.
Today, there are commercially available IMS detection systems that will detect most 
chemical agents and many TIMs (see Figure 5-13). They are suitable for integration 
into a building's HVAC system, can interface with HVAC control systems, have 
reasonable maintenance requirements (every 3 months), low false alarm rates, and 
can be programmed to detect specific chemical agents. 
Biological Detectors. The current state of biological detection technology is very 
different from that of chemical agent detection technology. In general, most 
biological detection systems are currently in the research and early development 
stages. There are some commercially available devices that have limited utility 
(responding only to a small number of agents) and are generally high cost items. 
Because commercially available biological warfare (BW) detection systems and/or 
components exhibit limited utility in detecting and identifying BW agents and are 
also costly, it is strongly recommended that purchasers be very careful when con-
sidering any device that claims to detect BW agents. 
One reason for the lack of available biological detection equipment is that detection 
of biological agents requires extremely high sensitivity (because of the very low 
effective dose needed to cause infection and spread the disease) and an unusually 
high degree of selectivity (because of the large and diverse biological background in 
the environment). Another reason for the lack of biological detection equipment is 
that biological agents, compared to chemical agents, are very complex systems of 
molecules, which makes them much more difficult to identify. For example, 
ionization/ion mobility spectrometry, an excellent system for collection, detection, 
and identification of chemical agents, cannot detect or discriminate biological 
agents in their current forms. In fact, the need for high efficiency collection and 
concentration of the sample, high sensitivities, and high selectivities make almost all 
chemical detectors in their current form unusable for biological agent detection. 
Because of the need for high selectivity and sensitivity, biological detection systems 
are necessarily complex and expensive devices. In general, biological sensors can 
detect one specific agent, and can usually only be used once. Some biological sensors 
are in current use in the food industry. The U.S. military is developing several de-
tection systems that show some promise. However, these systems are very complicated, 
require highly trained operators, extensive maintenance, and are extremely expensive 
to purchase and operate. 
For all these reasons, biological detection technologies will not be discussed herein. 
One alternative could be to use particle detectors. In theory, biological agents could 
be identified by a particle detector based on their characteristic size range. In fact, 
most biological detectors use trigger or cue technology to identify a change in the 
particulate background at the sensor to trigger the additional components of the 
detection system into operation. However, in practice, there are numerous problems 
when attempting to identify biological agents with particle detectors. Particulates in 
the atmosphere originate from a number of sources. Dust, dirt, pollen, and fog are all 
examples of naturally occurring particulates found in the air. Manmade particulates 
such as engine exhaust, smoke, and industrial effluents (smokestacks) also 
contribute significantly to the environmental particulate background. The 
particulate background can change on a minute-by-minute basis, depending on the 
meteorological conditions at the time. For example, the particulate background next 
to a road will change dramatically, depending on whether there is traffic on the road 
disturbing the dust, or if the road is empty. Likewise, if there is little wind, not many 
particulates are carried into the atmosphere; however, when the wind begins to blow, 
it can carry many particulates from the immediate vicinity, as well as from remote 
locations. The challenge for a biological detection system is to be able to 
discriminate between all of the naturally occurring particulates and the biological 
agent particulates. Thus, identification of biological agents with particle detectors 
alone may be extremely difficult.
5.7 INDICATIONS OF CBR CONTAMINATION
Most hazardous chemicals have warning properties that provide a practical means for 
detecting a hazard and initiating protective actions. Such warning properties make 
chemicals perceptible; for example, vapors or gases can be perceived by the human 
senses (i.e., smell, sight, taste, or irritation of the eyes, skin, or respiratory tract) 
before serious effects occur. The distinction between perceptible and imperceptible 
agents is not an exact one. The concentrations at which a person can detect an odor 
vary from person to person, and these thresholds also vary relative to the 
concentration that can produce immediate, injurious effects.
Most of the industrial chemicals and chemical-warfare agents are readily detectable 
by smell. Soldiers in World Wars I and II were taught to identify, by smell, such agents 
as mustard, phosgene, and chlorine, and this detection method proved effective for 
determining when to put on and take off a gas mask. An exception is the chemical-
warfare agent sarin, which is odorless and colorless in its pure form and, therefore, 
imperceptible. Among the most common toxic industrial chemicals, carbon 
monoxide is one of the few that is imperceptible. 
Biological agents are also imperceptible and there are no detection devices that can 
determine their presence in the air in real time. Current methods for detecting 
bacterial spores, such as anthrax, require a trained operator and expensive 
equipment. It is not currently possible to base protective responses to biological 
agents on detection.
Researchers are working on a prototype device to automatically and continuously 
monitor the air for the presence of bacterial spores. The device would continuously 
sample the air and use microwaves to trigger a chemical reaction, the intensity of 
which would correspond to the concentration of bacterial spores in the sample. If an 
increase in spore concentration is detected, an alarm similar to a smoke detector 
would sound and a technician would respond and use traditional sampling and 
analysis to confirm the presence of anthrax spores. Researchers hope the device 
response time will be fast enough to help prevent widespread contamination.
In the absence of a warning property, people can be alerted to some airborne hazards 
by observing symptoms or effects in others. This provides a practical means for 
initiating protective actions, because the susceptibility to hazardous materials varies 
from person to person. The concentrations of airborne materials may also vary 
substantially within a given building or room, producing a hazard that may be greater 
to some occupants than to others.
Other warning signs of a hazard may involve seeing and hearing something out of 
the ordinary, such as the hiss of a rapid release from a pressurized cylinder. 
Awareness to warning properties, signs, and symptoms in other people is the basis of 
a protective action plan. Such a plan should apply four possible protective actions: 
sheltering in place, using protective masks, evacuating, and purging, as already 
discussed in this chapter.
For protection against imperceptible agents, the only practical protective measures 
are those that are continuously in place, such as filtering all air brought into the 
building on a continuous basis and using automatic, real-time sensors that are 
capable of detecting the imperceptible agents.
Chemical, biological, and radiological materials, as well as industrial agents, may 
travel in the air as a gas or on surfaces we physically contact. Dispersion methods may 
be as simple as placing a container in a heavily used area, opening a container, or 
using conventional (garden)/commercial spray devices, or as elaborate as detonating 
an aerosol. 
Chemical incidents are characterized by the rapid onset (minutes to hours) of 
medical symptoms and easily observed indicators (e.g., colored residue, dead foliage, 
pungent odor, and dead animals, birds, fish, or insects; see Table 5-2 and Figure 5-14). 
In the case of a biological incident, the onset of symptoms takes days to weeks and, 
typically, there will be no characteristic indicators (see Table 5-3 and Figure 5-15). 
Because of the delayed onset of symptoms in a biological incident, the area affected 
may be greater due to the migration of infected individuals.
In the case of a radiological incident, the onset of symptoms also takes days to weeks 
to occur and typically there will be no characteristic indicators (see Table 5-4 and 
Figure 5-16). Radiological materials are not recognizable by the senses because they 
are colorless and odorless. 
Specialized equipment is required to determine the size of the affected area and if the 
level of radioactivity presents an immediate or long-term health hazard. Because of 
the delayed onset of symptoms in a radiological incident, the affected area may be 
greater due to the migration of contaminated individuals


1This chapter includes a number of protective measures that are included for informational purposes only. It is not the intention of FEMA to endorse 
any particular product or protective measure


 SOURCE: MSA INTERNATIONA


Figure 5-1 Universal-fit escape hoo


Airborne contaminants can be gases, vapors, or aerosols (small solid and liquid particles). Most 
biological and radiological agents are aerosols, whereas most chemical warfare agents are gaseous


Figure 5-2 Scanning electron microscope image of a polyester-glass fiber filte


SOURCE: CDC/NIOSH PUBLICATION NO. 2003-136, GUIDANCE FOR FILTRATION AND AIR CLEANING SYSTEMS TO PROTECT 
BUILDING ENVIRONMENTS FROM AIRBORNE CHEMICAL, BIOLOGICAL, OR RADIOLOGICAL ATTACKS, APRIL 200


Figure 5-3 Four primary filter collection mechanism


SOURCE: CDC/NIOSH PUBLICATION NO. 2003-136, GUIDANCE FOR FILTRATION AND AIR CLEANING SYSTEMS TO PROTECT 
BUILDING ENVIRONMENTS FROM AIRBORNE CHEMICAL, BIOLOGICAL, OR RADIOLOGICAL ATTACKS, APRIL 200


Figure 5-4 Classic collection efficiency curv


SOURCE: CDC/NIOSH PUBLICATION NO. 2003-136, GUIDANCE FOR FILTRATION AND AIR CLEANING SYSTEMS TO PROTECT 
BUILDING ENVIRONMENTS FROM AIRBORNE CHEMICAL, BIOLOGICAL, OR RADIOLOGICAL ATTACKS, APRIL 200


Table 5-1: Comparison of ASHRAE Standards 52.1 and 52.2

ASHRAE 52.2
ASHRAE 
52.1
Particl
e Size 
Range, 
m
Application
s

Particle Size Range


Tes
t
MER
V
3 to 
10 
m


1 to 
3 
m
0.3 
to 
1 

m
Arrestanc
e
Dus
t 
Spot
1
< 
20
%
-
-
< 
65%
< 
20
%
> 10
Residential,
light, 
pollen,
dust mites
2
< 20%
-
-
65 - 
70%
< 
20%



3
< 20%
-
-
70 - 
75%
< 
20%



4
< 20%
-
-
> 75%
< 
20%



5
20 - 
35
%
-
-
80 - 
85%
< 
20
%
3.0 - 10
Industrial,
dust, molds,
spores
6
35 - 
50%
-
-
> 90%
< 
20%



7
50 - 
70%
-
-
> 90%
20 - 
25%



8
> 70%
-
-
> 95%
25 - 
30%



9
> 
85
%
< 50%
-
> 
95%
40 - 
45
%
1.0  
3.0
Industrial,
Legionella,
dust
1
0
> 85%
50 - 
65
%
-
> 95%
50 - 
55%



1
1
> 85%
65 - 
80
%
-
> 98%
60 - 
65%



12
> 90%
> 
80
%
-
> 98%
70 - 
75%



13
> 
90
%
> 90%
< 75%
> 
98%
80 - 
90
%
0.3  
1.0
Hospitals,
Smoke 
removal, 
bacteria
1
4
> 90%
> 
90
%
75 - 85%
> 98%
90 - 
95%



1
5
> 90%
> 
90
%
85 - 95%
> 98%
~95
%



1
6
> 95%
> 
95
%
> 95%
> 98%
> 
95%



17
-
-
 
99.97
%
-
-
< 0.3
Clean 
rooms,
Surgery,
chem-bio,
viruses
18
-
-
 
99.99%
-
-



19
-
-
 
99.999%
-
-



20
-
-
 
99.9999
%
-
-





Note:  This table is adapted from American Society of Heating, Refrigerating, and Air-conditioning 
Engineers (ASHRAE) Standard 52.2: Method of Testing General Ventilation Air-cleaning Devices 
for Removal Efficiency by Particle Size, Atlanta, GA., 1999 and Spengler, J.D., Samet, J.M., and 
McCarthy, J.F., Indoor air quality Handbook, New York, NY: McGraw-Hill, 2000


Figure 5-5  A bag filter and HEPA filter


SOURCE: TRION INCORPORATE


SOURCE: CDC/NIOSH PUBLICATION NO. 2003-136, GUIDANCE FOR FILTRATION AND AIR CLEANING SYSTEMS TO PROTECT 
BUILDING ENVIRONMENTS FROM AIRBORNE CHEMICAL, BIOLOGICAL, OR RADIOLOGICAL ATTACKS, APRIL 200


Figure 5-6 Comparison of filter collection efficiency based on particle siz


Figure 5-7 Typical performance of a HEPA 99.97


Figure 5-8 Scanning electron microscope image of activated carbon pore


SOURCE: CDC/NIOSH PUBLICATION NO. 2003-136, GUIDANCE FOR FILTRATION AND AIR CLEANING SYSTEMS TO PROTECT 
BUILDING ENVIRONMENTS FROM AIRBORNE CHEMICAL, BIOLOGICAL, OR RADIOLOGICAL ATTACKS, APRIL 200


Figure 5-9 Charcoal filter bed


SOURCE: FLANDERS CORPORATIO


Figure 5-10 UVGI array used for air disinfection with reflective surface


SOURCE: LUMALIER INCORPORATE


Figure 5-11 A military FFA 580 air filtration system containing both a HEPA filter and an ASZM-
TEDA carbon adsorber as part of an overpressure syste


Figure 5-12 A commercial air filtration uni


 SOURCE: TRION INCORPORATE


1 W. J. Kowalski, W. P. Bahnfleth, and T. S. Whittam, Filtration or Airborne Microorganisms: Modeling and Prediction  
http://www.engr.psu.edu/ae/wjk/fom.html.
2 W. J. Kowalski, Defending Buildings Against Bioterrorism, Engineering Systems, September 30, 2002 
http://www.esmagazine.com/CDA/ArticleInformation/features/BNP_Features_Item/0,2503,84858,00.html


Figure 5-13  An IMS chemical detector designed for installation in HVAC systems  


SOURCE: SMITHS DETECTIO


Table 5-2: Indicators of a Possible Chemical Incident

Dead animals, 
birds, fish
Not just an occasional roadkill, but numerous animals (wild and domestic, 
small and large), birds, and fish in the same area. 
Lack of insect life
If normal insect activity (ground, air, and/or water) is missing, check the 
ground/water surface/shore line for dead insects. If near water, check for 
dead fish/aquatic birds. 
Physical symptoms
Numerous individuals experiencing unexplained water-like blisters, wheals 
(like bee stings), pinpointed pupils, choking, respiratory ailments, and/or 
rashes. 
Mass casualties
Numerous individuals exhibiting unexplained serious health problems ranging 
from nausea to disorientation to difficulty in breathing to convulsions to 
death. 
Definite pattern of 
casualties
Casualties distributed in a pattern that may be associated with possible agent 
dissemination methods. 
Illness associated 
with confined 
geographic area 
Lower attack rates for people working indoors than those working outdoors, 
and vice versa. 
Unusual liquid 
droplets
Numerous surfaces exhibit oily droplets/film; numerous water surfaces have 
an oily film. (No recent rain.) 
Areas that look 
different in 
appearance
Not just a patch of dead weeds, but trees, shrubs, bushes, food crops, and/or 
lawns that are dead, discolored, or withered. (No current drought.) 
Unexplained odors
Smells may range from fruity to flowery to sharp/pungent to 
garlic/horseradish-like to bitter almonds/peach kernels to new mown 
hay. It is important to note that the particular odor is completely out of 
character with its surroundings. 
Low-lying clouds
Low-lying cloud/fog-like condition that is not explained by its surroundings. 
Unusual metal 
debris
Unexplained bomb/munitions-like material, especially if it contains a liquid. 
(No recent rain.) 


Gases  Toxic (Corrosive


Gases  Toxic and/or Corrosiv


Substances  Toxic (Non-Combustible


Figure 5-14 Placards associated with chemical incident


Table 5-3: Indicators of a Possible Biological Incident

Unusual numbers 
of sick or dying 
people or animals 
Any number of symptoms may occur. As a first responder, strong consideration 
should be given to calling local hospitals to see if additional casualities with 
similar symptoms have been observed. Casualties may occur hours to days or 
weeks after an incident has occurred. The time required before symptoms are 
observed is dependent on the biological agent used and the dose received. 
Additional symptoms likely to occur include unexplained gastrointestinal 
illnesses and upper respiratory problems similar to flu/colds. 
Unscheduled and 
unusual spray 
being 
disseminated 
Especially if outdoors during periods of darkness. 
Abandoned spray 
devices
Devices will have no distinct odors. 



Infectious Substance


 Figure 5-15 Placards associated with biological incident


Table 5-4: Indicators of a Possible Radiological Incident

Unusual numbers of 
sick or dying people 
or animals 
As a first responder, strong consideration should be given to calling local 
hospitals to see if additional casualties with similar symptoms have been 
observed. Casualties may occur hours to days or weeks after an incident 
has occurred. The time required before symptoms are observed is dependent 
on the radioactive material used and the dose received. Additional 
symptoms likely to occur include skin reddening and, in severe cases, 
vomiting. 
Unusual metal debris
Unexplained bomb/munitions-like material. 
Radiation symbols
Containers may display a radiation symbol. 
Heat emitting 
material
Material that seems to emit heat without any sign of an external heating 
source. 
Glowing 
material/particles
If the material is strongly radioactive, it may emit a radioluminescence. 


Radioactive Material


Figure 5-16 Placards associated with radiological incident




ACRONYMS     


This appendix contains some acronyms that do not actually appear in this manual. 
They have been included to present a comprehensive list that pertains to this series of 
publications.
A
AA&E Arms, Ammunition, and Explosives
AAR After Action Report
ACL Access Control List
ACP access control point
ACSAccess Control System
ADAAmericans with Disabilities Act
ADAAGAmericans with Disabilities Act Accessibility Guidelines
AECS Automated Entry Control System
AFJMAN Air Force Joint Manual, also may be known as AFMAN (I) for Air Force 
Manual 
AFMAN Air Force Manual
ALERT Automated Local Evaluation in Real Time
AMS Aerial Measuring System
ANS Alert and Notification System
ANSI American National Standards Institute
ANSIR Awareness of National Security Issues and Response Program
AOR Area of Responsibility
AP armor piercing
APHL Agency for Public Health Laboratories
ARAC Atmospheric Release Advisory Capability
ARC American Red Cross
ARG Accident Response Group
ARS Agriculture Research Service
ASCEAmerican Society of Civil Engineers
ASHRAEAmerican Society of Heating, Refrigerating, and Air-Conditioning 
Engineers
ASTHO Association for State and Territorial Health Officials
ASTMAmerican Society for Testing and Materials
ASZM-TEDAcopper-silver-zinc-molybdenum-triethylenediamine
AT Antiterrorism
ATC Air Traffic Control
ATFBureau of Alcohol, Tobacco, and Firearms
ATSD(CS) Assistant to the Secretary of Defense for Civil Support
ATSDR Agency for Toxic Substances and Disease Registry
AWGAmerican wire gauge
B
BCA Benefit/Cost Analysis
BCCBackup Control Center
BCP Business Continuity Plan
BDC Bomb Data Center
BLASTOPBlast-Resistant Window Program
BMSbalanced magnetic switch
BWbiological warfare
C
CAMEO Computer-Aided Management of Emergency Operations
CB Citizens Band
CBIAC Chemical and Biological Defense Information and Analysis Center
CBR chemical, biological, or radiological
CBRNE chemical, biological, radiological, nuclear, or explosive
CCTV closed circuit television
CDC Centers for Disease Control and Prevention
CDR Call Detail Report
CDRG Catastrophic Disaster Response Group
CEO Chief Executive Officer
CEPPO Chemical Emergency Preparedness and Prevention Office
CERCLA Comprehensive Environmental Response, Compensation, and Liability Act
CERT Community Emergency Response Team
CFDComputational Fluid Dynamics
CFO Chief Financial Officer
CFR Code of Federal Regulations
CHEMTREC Chemical Manufacturers Association Chemical Transportation 
Emergency Center 
CHPPM Center for Health Promotion and Preventive Medicine
CIAO Chief Infrastructure Assurance Office
CIAO Critical Infrastructure Assurance Officer
CICG Critical Infrastructure Coordination Group
CIO Chief Information Officer
CIP Critical Infrastructure Protection
CIRG Crisis Incident Response Group
CJCS Chairman of the Joint Chiefs of Staff
CM Consequence Management
CMCrisis Management
CMS Call Management System
CMU concrete masonry unit
CMU Crisis Management Unit (CIRG)
COB Continuity of Business
COBIT TM Control Objectives for Information Technology
CO/DO Central Office/Direct Outdial
CONEX Container Express
CONOPS Concept of Operations
COO Chief Operating Officer
COOP Continuity of Operations Plan
COR Class of Restriction
COS Class of Service
CPG Civil Preparedness Guide
CPTED Crime Prevention Through Environmental Design
CPX Command Post Exercise
CRU Crisis Response Unit
CSEPP Chemical Stockpile Emergency Preparedness Program
CSIConstruction Specifications Institute
CSREES Cooperative State Research, Education, and Extension Service
CST Civil Support Team
CSTE Council of State and Territorial Epidemiologists
CT Counterterrorism
CW/CBD Chemical Warfare/Contraband Detection
D
DBMS Database Management System
DBT Design Basis Threat
DBU dial backup
DD Data Dictionary
DES Data Encryption Standard
DEST Domestic Emergency Support Team
DFO Disaster Field Office
DHS Department of Homeland Security
DISA Direct Inward System Access
DMA Disaster Mitigation Act of 2000
DMAT Disaster Medical Assistance Team 
DMCR Disaster Management Central Resource
DMORT Disaster Mortuary Operational Response Team
DOCDepartment of Commerce
DoD Department of Defense
DOE Department of Energy
DOJ Department of Justice
DOS Department of State
DOT Department of Transportation
DPP Domestic Preparedness Program
DRC Disaster Recovery Center
DTCTPS Domestic Terrorism/Counterterrorism Planning Section (FBI HQ)
DTIC Defense Technical Information Center
DTMdata-transmission media
DWI Disaster Welfare Information
E
EAS Emergency Alert System
ECL Emergency Classification Level
EECS Electronic Entry Control System
EFR Emergency First Responder
EM Emergency Management
EMAC Emergency Medical Assistance Compact
EMI Emergency Management Institute
EMP electromagnetic pulse
EMS Emergency Medical Services
EOC Emergency Operations Center
EOD Explosive Ordnance Disposal
EOP Emergency Operating Plan
EOP Emergency Operations Plan
EPA Environmental Protection Agency
EPCRA Emergency Planning and Community Right-to-Know Act
EPG Emergency Planning Guide
EPI Emergency Public Information
EP&RDirectorate of Emergency Preparedness and Response (DHS)
EPZ Emergency Planning Zone
ERPEmergency Response Plan
ERT Emergency Response Team
ERT-A Emergency Response Team Advance Element
ERT-N Emergency Response Team National
ERTU Evidence Response Team Unit
ESC Expandable Shelter Container
ESF Emergency Support Function
ESS Electronic Security System
EST Emergency Support Team
ETLEngineering Technical Letter
EU explosives unit

F
FAsT Field Assessment Team
FBI Federal Bureau of Investigation
FCCFederal Communications Commission
FCCFire Control Center
FCO Federal Coordinating Officer
FEMfinite element
FEMA Federal Emergency Management Agency
FEST Foreign Emergency Support Team
FHBM Flood Hazard Boundary Map
FIA Federal Insurance Administration 
FIPS Federal Information Processing Standard
FIRM Flood Insurance Rate Map
FIS Flood Insurance Study
FISCAM Federal Information Systems Control Audit Manual
FMFIA Federal Managers Financial Integrity Act
FNS Food and Nutrition Service
FOIA Freedom of Information Act
FOUO For Official Use Only
FPEIS Final Programmatic Environmental Impact Statement
FRERP Federal Radiological Emergency Response Plan
FRF fragment retention film
FRL Facility Restriction Level
FRMAC Federal Radiological Monitoring and Assessment Center
FRP Federal Response Plan
FS Forest Service
FSTFS Frame-Supported Tensioned Fabric Structure
FTP File Transfer Protocol
FTX Functional Training Exercise
G
GAO General Accounting Office
GAR Governors Authorized Representative
GC/MSgas chromatograph/mass spectrometer
GIS Geographic Information System
GP General Purpose
GPSGlobal Positioning System
GSA General Services Administration
H
HazMat hazardous material
HAZUS Hazards U.S.
HEPA high efficiency particulate air
HEUhighly enriched uranium
HFhigh frequency
HHS Department of Health and Human Services
HIRA Hazard Identification and Risk Assessment
HMRU Hazardous Materials Response Unit
HQ Headquarters
HRCQ Highway Route Controlled Quantity
HRT Hostage Rescue Team (CIRG)
HTIS Hazardous Technical Information Services (DoD)
HVAC heating, ventilation, and air conditioning
I
IC Incident Commander
ICDDC Interstate Civil Defense and Disaster Compact
ICP Incident Command Post
ICS Incident Command System
IDidentification
IDS Intrusion Detection System
IED Improvised Explosive Device
IEMS Integrated Emergency Management System
IESNAIlluminating Engineering Society of North America 
IID Improvised Incendiary Device
IMSion mobility spectrometry
IND Improvised Nuclear Device
IPL Initial Program Load
IRinfrared
IRZ Immediate Response Zone
IS Information System
ISACF Information Systems Audit and Control Foundation
ISCInteragency Security Committee
ISO International Organization for Standardization
ISP Internet Service Provider
IT Information Technology
J
JIC Joint Information Center
JIISEJoint Interagency Intelligence Support Element
JIS Joint Information System
JNACC Joint Nuclear Accident Coordinating Center
JOC Joint Operations Center
JSMGJoint Service Materiel Group
JTF-CS Joint Task Force for Civil Support
JTTF Joint Terrorism Task Force
JTWG Joint Terrorism Working Group
K
kHzkilohertz
kPakilo Pascal
L
LAN Local Area Network
LAW Light Antitank Weapon
LBNLLawrence Berkley National Lab
LCM Life-cycle Management
LEDlight-emitting diode
LEEDLeadership in Energy and Environmental Design
LEPC Local Emergency Planning Committee
LFlow frequency
LFA Lead Federal Agency
LLNL Lawrence Livermore National Laboratory
LOP level of protection
LOS line of sight
LPHA Local Public Health Agency
LPHS Local Public Health System
M
MAC Moves, Adds, Changes
MEDCOM Medical Command
MEI Minimum Essential Infrastructure
M/E/PMechanical/Electrical/Plumbing
MEP Mission Essential Process
MERVminimum efficiency reporting value
MMRS Metropolitan Medical Response System
MOU/A Memorandum of Understanding/Agreement
mph miles per hour
MPOPMinimum-Points-of-Presence
msmillisecond
MSCA Military Support to Civil Authorities 
MSDS Material Safety Data Sheet
MSS Medium Shelter System
MWmedium wave
N
NACCHO National Association for County and City Health Officials
NAP Nuclear Assessment Program
NAVFACNaval Facilities Command
NBC nuclear, biological, and chemical
NCJNational Criminal Justice
NCP National Contingency Plan (also known as National Oil and Hazardous 
Substances Pollution Contingency Plan)
NDA National Defense Area
NDMS National Disaster Medical System
NDPO National Domestic Preparedness Office
NEST Nuclear Emergency Search Team
NETC National Emergency Training Center
NFA National Fire Academy
NFIP National Flood Insurance Program
NFPANational Fire Protection Association
NFPCNational Fire Protection Code
NIJNational Institute of Justice
NIOSH National Institute for Occupational Safety and Health
NMRT National Medical Response Team
NMS Network Management System
NOAA National Oceanic and Atmospheric Administration
NRC National Response Center
NRC Nuclear Regulatory Commission
NRT National Response Team
NSC National Security Council
NTIS National Technical Information Service
NUREG Nuclear Regulation
NWS National Weather Service
O
OCCOperational Control Center
ODP Office of Disaster Preparedness
OEP Office of Emergency Preparedness
OES Office of Emergency Services
OFCM Office of the Federal Coordinator for Meteorology
OHS Office of Homeland Security
OJP Office of Justice Programs
O&Moperations and maintenance
OMB Office of Management and Budget
OPA Oil Pollution Act
OSC On-scene Coordinator
OSD Office of Secretary of Defense
OSHA Occupational Safety and Health Administration
OSLDPS Office for State and Local Domestic Preparedness Support
P
PaPascal
PA public address
PAZ Protective Action Zone
PBX Public Branch Exchange
PCpersonal computer
PCC Policy Coordinating Committee
PCCIP Presidents Commission on Critical Infrastructure Protection
PCM Procedures Control Manual
PDA personal data assistant
PDA Preliminary Damage Assessment
PDD Presidential Decision Directive
PHS Public Health Service
PIN Personal Identification Number
PIO Public Information Officer
PL Public Law
POC Point of Contact
PODprobability of detection
POIprobability of intrusion
POL Petroleum, Oils, and Lubricants
POVprivately owned vehicle
PPA Performance Partnership Agreement
ppmparts per million
PSEparticle size efficiency
psipounds per square inch
PT Preparedness, Training, and Exercises Directorate (FEMA)
PTE Potential Threat Element
PTZpan-tilt-zoom (camera)
PVBpolyvinyl butyral
PZ Precautionary Zone
R
RACES Radio Amateur Civil Emergency Service
RAP Radiological Assistance Program
RCRA Research Conservation and Recovery Act
RDD Radiological Dispersal Device
RDT&E Research, Development, Test, and Evaluation
REACT Radio Emergency Associated Communications Team
REAC/TS Radiation Emergency Assistance Center/Training Site
REMRoentgen Man Equivalent
REP Radiological Emergency Preparedness Program
RFradio frequency
ROC Regional Operations Center
ROD Record of Decision
RPG Rocket Propelled Grenade
RRIS Rapid Response Information System (FEMA)
RRP Regional Response Plan
RRT Regional Response Team
S
SAA State Administrative Agency
SAC Special Agent in Charge (FBI)
SAFEVUSafety Viewport Analysis Code 
SAME Specific Area Message Encoder
SARA Superfund Amendments and Reauthorization Act
SATCOMsatellite communications
SAWsurface acoustic wave
SBCCOM Soldier and Biological Chemical Command (U.S. Army)
SCADA Supervisory, Control, and Data Acquisition
SCBA Self-Contained Breathing Apparatus
SCCSecurity Control Center
SCO State Coordinating Officer
SDOFsingle-degree-of-freedom
SEA Southeast Asia
SEB State Emergency Board
SEL Standardized Equipment List
SEMA State Emergency Management Agency
SERC State Emergency Response Commission
SFOSenior FEMA Official
SIOC Strategic Information and Operations Center (FBI HQ)
SLA Service Level Agreement
SLG State and Local Guide
SNMSpecial Nuclear Material
SOP Standard Operating Procedure
SPCA Society for the Prevention of Cruelty to Animals
SPSA Super Power Small Arms
SSS Small Shelter System
STC Sound Transmission Class
SWAT Special Weapons and Tactics
T
TAC Trunk Access Codes
TDRtransferable development right
TEA Threat Environment Assessment
TEMPER Tent, Extendable, Modular, Personnel
TERC Tribal Emergency Response Commission
TIA Terrorist Incident Appendix
TIM toxic industrial material
TM Technical Manual
TNT trinitrotoluene
TRIS Toxic Release Inventory System
TSCtriple-standard concertina
TSO Time Share Option
TTGthermally tempered glass
U
UC Unified Command
UCS Unified Command System
UFASUniform Federal Accessibility Standards
UFCUnified Facilities Criteria
UL Underwriters Laboratories
ULPAultra low penetration air
UPS uninterrupted power supply
URVUVGI Rating Values
U.S.United States
USAUnited States Army
USAFUnited States Air Force
USC U.S. Code
USDA U.S. Department of Agriculture
USFA U.S. Fire Administration
USGBCU.S. Green Building Council
USGS U.S. Geological Survey
US&R Urban Search and Rescue
UVultraviolet
UVGIultraviolet germicidal irradiation
V
VA Department of Veterans Affairs
VAP Vulnerability Assessment Plan
VAV Variable Air Volume
VDN Vector Directory Number
VHFvery high frequency
VRU Voice Response Unit
W
WAN Wide Area Network
wgwater gauge
WINGARDWindow Glazing Analysis Response and Design
WINLACWindow Lite Analysis Code
WMD Weapons of Mass Destruction
WMD-CST WMD Civil Support Tea




GENERAL GLOSSARY     



This appendix contains some terms that do not actually appear in this manual. They 
have been included to present a comprehensive list that pertains to this series of 
publications.
A
Access control. Any combination of barriers, gates, electronic security equipment, 
and/or guards that can deny entry to unauthorized personnel or vehicles.
Access control point (ACP). A station at an entrance to a building or a portion of a 
building where identification is checked and people and hand-carried items are 
searched. 
Access controls. Procedures and controls that limit or detect access to minimum 
essential infrastructure resource elements (e.g., people, technology, applications, 
data, and/or facilities), thereby protecting these resources against loss of integrity, 
confidentiality, accountability, and/or availability. 
Access Control System (ACS). Also referred to as an Electronic Entry Control Systems; 
an electronic system that controls entry and egress from a building or area. 
Access Control System elements. Detection measures used to control vehicle or 
personnel entry into a protected area. Access Control System elements include locks, 
Electronic Entry Control Systems, and guards.  
Access group. A software configuration of an Access Control System that groups 
together access points or authorized users for easier arrangement and maintenance 
of the system. 
Access road. Any roadway such as a maintenance, delivery, service, emergency, or 
other special limited use road that is necessary for the operation of a building or 
structure.
Accountability. The explicit assignment of responsibilities for oversight of areas of 
control to executives, managers, staff, owners, providers, and users of minimum 
essential infrastructure resource elements. 
Acoustic eavesdropping. The use of listening devices to monitor voice 
communications or other audibly transmitted information with the objective to 
compromise information. 
Active vehicle barrier. An impediment placed at an access control point that may be 
manually or automatically deployed in response to detection of a threat. 
Aerosol. Fine liquid or solid particles suspended in a gas (e.g., fog or smoke).
Aggressor. Any person seeking to compromise a function or structure. 
Airborne contamination. Chemical or biological agents introduced into and fouling 
the source of supply of breathing or conditioning air. 
Airlock. A building entry configuration with which airflow from the outside can be 
prevented from entering a toxic-free area. An airlock uses two doors, only one of 
which can be opened at a time, and a blower system to maintain positive air pressures 
and purge contaminated air from the airlock before the second door is opened.  
Alarm assessment. Verification and evaluation of an alarm alert through the use of 
closed circuit television or human observation. Systems used for alarm assessment are 
designed to respond rapidly, automatically, and predictably to the receipt of alarms at 
the security center. 
Alarm printers. Alarm printers provide a hard-copy of all alarm events and system 
activity, as well as limited backup in case the visual display fails. 
Alarm priority. A hierarchy of alarms by order of importance. This is often used in 
larger systems to give priority to alarms with greater importance. 
Annunciation. A visual, audible, or other indication by a security system of a 
condition. 
Antiterrorism (AT). Defensive measures used to reduce the vulnerability of 
individuals, forces, and property to terrorist acts. 
Area Commander. A military commander with authority in a specific geographical 
area or military installation.
Area lighting. Lighting that illuminates a large exterior area. 
Areas of potential compromise. Categories where losses can occur that will impact 
either a departments or an agencys minimum essential infrastructure and its ability 
to conduct core functions and activities. 
Assessment. The evaluation and interpretation of measurements and other 
information to provide a basis for decision-making.
Assessment System elements. Detection measures used to assist guards in visual 
verification of Intrusion Detection System Alarms and Access Control System 
functions and to assist in visual detection by guards. Assessment System elements 
include closed circuit television and protective lighting. 
Asset. A resource of value requiring protection. An asset can be tangible (e.g., people, 
buildings, facilities, equipment, activities, operations, and information) or intangible 
(e.g., processes or a companys information and reputation).
Asset protection. Security program designed to protect personnel, facilities, and 
equipment, in all locations and situations, accomplished through planned and 
integrated application of combating terrorism, physical security, operations security, 
and personal protective services, and supported by intelligence, counterintelligence, 
and other security programs.
Asset value. The degree of debilitating impact that would be caused by the incapacity 
or destruction of an asset.
Attack. A hostile action resulting in the destruction, injury, or death to the civilian 
population, or damage or destruction to public and private property. 
Audible alarm device. An alarm device that produces an audible announcement (e.g., 
bell, horn, siren, etc.) of an alarm condition. 
B
Balanced magnetic switch. A door position switch utilizing a reed switch held in a 
balanced or center position by interacting magnetic fields when not in alarm 
condition. 
Ballistics attack. An attack in which small arms (e.g., pistols, submachine guns, 
shotguns, and rifles) are fired from a distance and rely on the flight of the projectile 
to damage the target.
Barbed tape or concertina. A coiled tape or coil of wires with wire barbs or blades 
deployed as an obstacle to human trespass or entry into an area.
Barbed wire. A double strand of wire with four-point barbs equally spaced along the 
wire deployed as an obstacle to human trespass or entry into an area. 
Barcode. A black bar printed on white paper or tape that can be easily read with an 
optical scanner. 
Biological agents. Living organisms or the materials derived from them that cause 
disease in or harm to humans, animals, or plants or cause deterioration of material. 
Biological agents may be used as liquid droplets, aerosols, or dry powders. 
Biometric reader. A device that gathers and analyzes biometric features. 
Biometrics. The use of physical characteristics of the human body as a unique 
identification method. 
Blast curtains. Heavy curtains made of blast-resistant materials that could protect the 
occupants of a room from flying debris.
Blast-resistant glazing. Window opening glazing that is resistant to blast effects 
because of the interrelated function of the frame and glazing material properties 
frequently dependent upon tempered glass, polycarbonate, or laminated glazing. 
Blast vulnerability envelope. The geographical area in which an explosive device will 
cause damage to assets.
Bollard. A vehicle barrier consisting of a cylinder, usually made of steel and 
sometimes filled with concrete, placed on end in the ground and spaced about 3 feet 
apart to prevent vehicles from passing, but allowing entrance of pedestrians and 
bicycles. 
Boundary penetration sensor.  An interior intrusion detection sensor that detects 
attempts by individuals to penetrate or enter a building. 
Building hardening. Enhanced construction that reduces vulnerability to external 
blast and ballistic attacks. 
Building separation. The distance between closest points on the exterior walls of 
adjacent buildings or structures.
Business Continuity Program (BCP). An ongoing process supported by senior 
management and funded to ensure that the necessary steps are taken to identify the 
impact of potential losses, maintain viable recovery strategies and recovery plans, and 
ensure continuity services through personnel training, plan testing, and 
maintenance.
C
Cable barrier. Cable or wire rope anchored to and suspended off the ground or 
attached to chain-link fence to act as a barrier to moving vehicles. 
Capacitance sensor. A device that detects an intruder approaching or touching a 
metal object by sensing a change in capacitance between the object and the ground. 
Card reader. A device that gathers or reads information when a card is presented as 
an identification method. 
Chemical agent. A chemical substance that is intended to kill, seriously injure, or 
incapacitate people through physiological effects. Generally separated by severity of 
effect (e.g., lethal, blister, and incapacitating).
Chimney effect. Air movement in a building between floors caused by differential air 
temperature (differences in density), between the air inside and outside the building. 
It occurs in vertical shafts, such as elevators, stairwells, and conduit/wiring/piping 
chases. Hotter air inside the building will rise and be replaced by infiltration with 
colder outside air through the lower portions of the building. Conversely, reversing 
the temperature will reverse the flow (down the chimney). Also known as stack effect.
Clear zone. An area that is clear of visual obstructions and landscape materials that 
could conceal a threat or perpetrator.
Closed circuit television (CCTV). An electronic system of cameras, control equipment, 
recorders, and related apparatus used for surveillance or alarm assessment. 
CCTV pan-tilt-zoom camera (PTZ). A CCTV camera that can move side to side, up and 
down, and zoom in or out. 
CCTV pan-tilt-zoom control. The method of controlling the PTZ functions of a 
camera. 
CCTV pan-tilt-zoom controller. The operator interface for performing PTZ control. 
CCTV switcher. A piece of equipment capable of presenting multiple video images to 
various monitors, recorders, etc. 
Collateral damage. Injury or damage to assets that are not the primary target of an 
attack.
Combating terrorism. The full range of federal programs and activities applied 
against terrorism, domestically and abroad, regardless of the source or motive.
Community. A political entity that has the authority to adopt and enforce laws and 
ordinances for the area under its jurisdiction.  In most cases, the community is an 
incorporated town, city, township, village, or unincorporated area of a county; 
however, each state defines its own political subdivisions and forms of government.  
Components and cladding. Elements of the building envelope that do not qualify as 
part of the main wind-force resisting system.
Confidentiality. The protection of sensitive information against unauthorized 
disclosure and sensitive facilities from physical, technical, or electronic penetration 
or exploitation. 
Consequence Management. Measures to protect public health and safety, restore 
essential government services, and provide emergency relief to governments, 
businesses, and individuals affected by the consequences of terrorism. State and local 
governments exercise the primary authority to respond to the consequences of 
terrorism. 
Contamination. The undesirable deposition of a chemical, biological, or radiological 
material on the surface of structures, areas, objects, or people. 
Continuity of services and operations. Controls to ensure that, when unexpected 
events occur, departmental/agency minimum essential infrastructure services and 
operations, including computer operations, continue without interruption or are 
promptly resumed, and that critical and sensitive data are protected through adequate 
contingency and business recovery plans and exercises.  
Control center. A centrally located room or facility staffed by personnel charged with 
the oversight of specific situations and/or equipment. 
Controlled area. An area into which access is controlled or limited. It is that portion 
of a restricted area usually near or surrounding a limited or exclusion area. Correlates 
with exclusion zone.
Controlled lighting. Illumination of specific areas or sections. 
Controlled perimeter. A physical boundary at which vehicle and personnel access is 
controlled at the perimeter of a site. Access control at a controlled perimeter should 
demonstrate the capability to search individuals and vehicles. 
Conventional construction. Building construction that is not specifically designed to 
resist weapons, explosives, or chemical, biological, and radiological effects. 
Conventional construction is designed only to resist common loadings and 
environmental effects such as wind, seismic, and snow loads.
Coordinate. To advance systematically an exchange of information among principals 
who have or may have a need to know certain information in order to carry out their 
roles in a response.
Counterintelligence. Information gathered and activities conducted to protect against: 
espionage, other intelligence activities, sabotage, or assassinations conducted for or 
on behalf of foreign powers, organizations, or persons; or international terrorist 
activities, excluding personnel, physical, document, and communications security 
programs.
Counterterrorism (CT). Offensive measures taken to prevent, deter, and respond to 
terrorism.
Covert entry. Attempts to enter a facility by using false credentials or stealth. 
Crash bar. A mechanical egress device located on the interior side of a door that 
unlocks the door when pressure is applied in the direction of egress. 
Crime Prevention Through Environmental Design (CPTED). A crime prevention 
strategy based on evidence that the design and form of the built environment can 
influence human behavior. CPTED usually involves the use of three principles: 
natural surveillance (by placing physical features, activities, and people to maximize 
visibility); natural access control (through the judicial placement of entrances, exits, 
fencing, landscaping, and lighting); and territorial reinforcement (using buildings, 
fences, pavement, signs, and landscaping to express ownership).
Crisis Management (CM). The measures taken to identify, acquire, and plan the use of 
resources needed to anticipate, prevent, and/or resolve a threat or act of terrorism. 
Critical assets. Those assets essential to the minimum operations of the organization, 
and to ensure the health and safety of the general public.
Critical infrastructure. Primary infrastructure systems (e.g., utilities, 
telecommunications, transportation, etc.) whose incapacity would have a debilitating 
impact on the organizations ability to function.
D
Damage assessment. The process used to appraise or determine the number of 
injuries and deaths, damage to public and private property, and the status of key 
facilities and services (e.g., hospitals and other health care facilities, fire and police 
stations, communications networks, water and sanitation systems, utilities, and 
transportation networks) resulting from a manmade or natural disaster.  
Data gathering panel. A local processing unit that retrieves, processes, stores, and/or 
acts on information in the field. 
Data transmission equipment. A path for transmitting data between two or more 
components (e.g., a sensor and alarm reporting system, a card reader and controller, 
a CCTV camera and monitor, or a transmitter and receiver). 
Decontamination. The reduction or removal of a chemical, biological, or radiological 
material from the surface of a structure, area, object, or person. 
Defense layer. Building design or exterior perimeter barriers intended to delay 
attempted forced entry. 
Defensive measures. Protective measures that delay or prevent attack on an asset or 
that shield the asset from weapons, explosives, and CBR effects. Defensive measures 
include site work and building design.
Delay rating. A measure of the effectiveness of penetration protection of a defense 
layer. 
Design Basis Threat (DBT). The threat (e.g., tactics and associated weapons, tools, or 
explosives) against which assets within a building must be protected and upon which 
the security engineering design of the building is based.
Design constraint. Anything that restricts the design options for a protective system or 
that creates additional problems for which the design must compensate.
Design opportunity. Anything that enhances protection, reduces requirements for 
protective measures, or solves a design problem. 
Design team. A group of individuals from various engineering and architectural 
disciplines responsible for the protective system design. 
Detection layer. A ring of intrusion detection sensors located on or adjacent to a 
defensive layer or between two defensive layers. 
Detection measures. Protective measures that detect intruders, weapons, or explosives; 
assist in assessing the validity of detection; control access to protected areas; and 
communicate the appropriate information to the response force. Detection measures 
include Detection Systems, Assessment Systems, and Access Control System elements. 
Detection System elements. Detection measures that detect the presence of intruders, 
weapons, or explosives. Detection System elements include Intrusion Detection 
Systems, weapons and explosives detectors, and guards. 
Disaster. An occurrence of a natural catastrophe, technological accident, or human-
caused event that has resulted in severe property damage, deaths, and/or multiple 
injuries. 
Disaster Field Office (DFO). The office established in or near the designated area of a 
Presidentially declared major disaster to support federal and state response and 
recovery operations. 
Disaster Recovery Center (DRC). Places established in the area of a Presidentially 
declared major disaster, as soon as practicable, to provide victims the opportunity to 
apply in person for assistance and/or obtain information relating to that assistance. 
Domestic terrorism. The unlawful use, or threatened use, of force or violence by a 
group or individual based and operating entirely within the United States or Puerto 
Rico without foreign direction committed against persons or property to intimidate 
or coerce a government, the civilian population, or any segment thereof in 
furtherance of political or social objectives. 
Door position switch. A switch that changes state based on whether or not a door is 
closed. Typically, a switch mounted in a frame that is actuated by a magnet in a door. 
Door strike, electronic. An electromechanical lock that releases a door plunger to 
unlock the door. Typically, an electronic door strike is mounted in place of or near a 
normal door strike plate.  
Dose rate (radiation). A general term indicating the quantity (total or accumulated) of 
ionizing radiation or energy absorbed by a person or animal, per unit of time.  
Dosimeter. An instrument for measuring and registering total accumulated exposure 
to ionizing radiation.  
Dual technology sensor. A sensor that combines two different technologies in one 
unit.  
Duress alarm devices. Also known as panic buttons, these devices are designated 
specifically to initiate a panic alarm. 
E
Effective stand-off distance. A stand-off distance at which the required level of 
protection can be shown to be achieved through analysis or can be achieved through 
building hardening or other mitigating construction or retrofit.
Electromagnetic pulse (EMP). A sharp pulse of energy radiated instantaneously by a 
nuclear detonation that may affect or damage electronic components and 
equipment. EMP can also be generated in lesser intensity by non-nuclear means in 
specific frequency ranges to perform the same disruptive function.
Electronic emanations. Electromagnetic emissions from computers, communications, 
electronics, wiring, and related equipment.
Electronic-emanations eavesdropping. Use of electronic-emanation surveillance 
equipment from outside a facility or its restricted area to monitor electronic 
emanations from computers, communications, and related equipment.
Electronic Entry Control Systems (EECS). Electronic devices that automatically verify 
authorization for a person to enter or exit a controlled area.  
Electronic Security System (ESS). An integrated system that encompasses interior and 
exterior sensors, closed circuit television systems for assessment of alarm conditions, 
Electronic Entry Control Systems, data transmission media, and alarm reporting 
systems for monitoring, control, and display of various alarm and system 
information.  
Emergency. Any natural or human-caused situation that results in or may result in 
substantial injury or harm to the population or substantial damage to or loss of 
property.
Emergency Alert System (EAS). A communications system of broadcast stations and 
interconnecting facilities authorized by the Federal Communications Commission 
(FCC). The system provides the President and other national, state, and local officials 
the means to broadcast emergency information to the public before, during, and 
after disasters.  
Emergency Environmental Health Services. Services required to correct or improve 
damaging environmental health effects on humans, including inspection for food 
contamination, inspection for water contamination, and vector control; providing 
for sewage and solid waste inspection and disposal; cleanup and disposal of 
hazardous materials; and sanitation inspection for emergency shelter facilities.  
Emergency Medical Services (EMS). Services including personnel, facilities, and 
equipment required to ensure proper medical care for the sick and injured from the 
time of injury to the time of final disposition, including medical disposition within a 
hospital, temporary medical facility, or special care facility; release from the site; or 
declared dead. Further, Emergency Medical Services specifically include those 
services immediately required to ensure proper medical care and specialized 
treatment for patients in a hospital and coordination of related hospital services. 
Emergency Mortuary Services. Services required to assure adequate death 
investigation, identification, and disposition of bodies; removal, temporary storage, 
and transportation of bodies to temporary morgue facilities; notification of next of 
kin; and coordination of mortuary services and burial of unclaimed bodies. 
Emergency Operations Center (EOC). The protected site from which state and local 
civil government officials coordinate, monitor, and direct emergency response 
activities during an emergency. 
Emergency Operations Plan (EOP). A document that describes how people and 
property will be protected in disaster and disaster threat situations; details who is 
responsible for carrying out specific actions; identifies the personnel, equipment, 
facilities, supplies, and other resources available for use in the disaster; and outlines 
how all actions will be coordinated. 
Emergency Planning Zones (EPZ). Areas around a facility for which planning is 
needed to ensure prompt and effective actions are taken to protect the health and 
safety of the public if an accident or disaster occurs. In the Radiological Emergency 
Preparedness Program, the two EPZs are:
Plume Exposure Pathway (10-mile EPZ). A circular geographic zone (with a 
10-mile radius centered at the nuclear power plant) for which plans are 
developed to protect the public against exposure to radiation emanating 
from a radioactive plume caused as a result of an accident at the nuclear 
power plant. 
Ingestion Pathway (50-mile EPZ). A circular geographic zone (with a 50-
mile radius centered at the nuclear power plant) for which plans are 
developed to protect the public from the ingestion of water or food 
contaminated as a result of a nuclear power plant accident. 
In the Chemical Stockpile Emergency Preparedness Program (CSEPP), the EPZ 
is divided into three concentric circular zones:
Immediate Response Zone (IRZ). A circular zone ranging from 10 to 15 
kilometers (6 to 9 miles) from the potential chemical event source, 
depending on the stockpile location on-post. Emergency response plans 
developed for the IRZ must provide for the most rapid and effective 
protective actions possible, because the IRZ will have the highest 
concentration of agent and the least amount of warning time. 
Protective Action Zone (PAZ). An area that extends beyond the IRZ to 
approximately 16 to 50 kilometers (10 to 30 miles) from the stockpile 
location. The PAZ is that area where public protective actions may still be 
necessary in case of an accidental release of chemical agent, but where the 
available warning and response time is such that most people could 
evacuate. However, other responses (e.g., sheltering) may be appropriate 
for institutions and special populations that could not evacuate within the 
available time. 
Precautionary Zone (PZ). The outermost portion of the EPZ for CSEPP, 
extending from the PAZ outer boundary to a distance where the risk of 
adverse impacts to humans is negligible. Because of the increased warning 
and response time available for implementation of response actions in the 
PZ, detailed local emergency planning is not required, although 
Consequence Management planning may be appropriate. 
Emergency Public Information (EPI). Information that is disseminated primarily in 
anticipation of an emergency or at the actual time of an emergency and, in addition 
to providing information, frequently directs actions, instructs, and transmits direct 
orders.
Emergency Response Team (ERT). An interagency team, consisting of the lead 
representative from each federal department or agency assigned primary 
responsibility for an ESF and key members of the FCOs staff, formed to assist the 
FCO in carrying out his/her coordination responsibilities. 
Emergency Response Team Advance Element (ERT-A). For federal disaster response 
and recovery activities under the Stafford Act, the portion of the ERT that is first 
deployed to the field to respond to a disaster incident. The ERT-A is the nucleus of 
the full ERT. 
Emergency Response Team National (ERT-N). An ERT that has been established and 
rostered for deployment to catastrophic disasters where the resources of the FEMA 
Region have been, or are expected to be, overwhelmed. Three ERT-Ns have been 
established. 
Emergency Support Function (ESF). In the Federal Response Plan (FRP), a functional 
area of response activity established to facilitate the delivery of federal assistance 
required during the immediate response phase of a disaster to save lives, protect 
property and public health, and to maintain public safety. ESFs represent those types 
of federal assistance that the state will most likely need because of the impact of a 
catastrophic or significant disaster on its own resources and response capabilities, or 
because of the specialized or unique nature of the assistance required. ESF missions 
are designed to supplement state and local response efforts. 
Emergency Support Team (EST). An interagency group operating from FEMA 
Headquarters. The EST oversees the national-level response support effort under the 
FRP and coordinates activities with the ESF primary and support agencies in 
supporting federal requirements in the field. 
Entity-wide security. Planning and management that provides a framework and 
continuing cycle of activity for managing risk, developing security policies, assigning 
responsibilities, and monitoring the adequacy of the entitys physical and cyber 
security controls. 
Entry control point. A continuously or intermittently manned station at which entry 
to sensitive or restricted areas is controlled. 
Entry control stations. Entry control stations should be provided at main perimeter 
entrances where security personnel are present. Entry control stations should be 
located as close as practical to the perimeter entrance to permit personnel inside the 
station to maintain constant surveillance over the entrance and its approaches. 
Equipment closet. A room where field control equipment such as data gathering 
panels and power supplies are typically located. 
Evacuation. Organized, phased, and supervised dispersal of people from dangerous or 
potentially dangerous areas. 
Evacuation, mandatory or directed. This is a warning to persons within the 
designated area that an imminent threat to life and property exists and individuals 
MUST evacuate in accordance with the instructions of local officials.  
Evacuation, spontaneous. Residents or citizens in the threatened areas observe an 
emergency event or receive unofficial word of an actual or perceived threat and, 
without receiving instructions to do so, elect to evacuate the area. Their movement, 
means, and direction of travel are unorganized and unsupervised.
Evacuation, voluntary. This is a warning to persons within a designated area that a 
threat to life and property exists or is likely to exist in the immediate future. 
Individuals issued this type of warning or order are NOT required to evacuate; 
however, it would be to their advantage to do so.  
Evacuees. All persons removed or moving from areas threatened or struck by a 
disaster. 
Exclusion area. A restricted area containing a security interest. Uncontrolled 
movement permits direct access to the item. See controlled area and limited area.
Exclusion zone. An area around an asset that has controlled entry with highly 
restrictive access. See controlled area.
Explosives disposal container. A small container into which small quantities of 
explosives may be placed to contain their blast pressures and fragments if the 
explosive detonates. 
F
Facial recognition. A biometric technology that is based on features of the human 
face.
Federal Coordinating Officer (FCO). The person appointed by the FEMA Director to 
coordinate federal assistance in a Presidentially declared emergency or major 
disaster.
Federal On-scene Commander. The FBI official designated upon JOC activation to 
ensure appropriate coordination of the overall United States government response 
with federal, state, and local authorities, until such time as the Attorney General 
transfers the LFA role to FEMA.
Federal Response Plan (FRP). The FRP establishes a process and structure for the 
systematic, coordinated, and effective delivery of federal assistance to address the 
consequences of any major disaster or emergency. 
Fence protection. An intrusion detection technology that detects a person crossing a 
fence by various methods such as climbing, crawling, cutting, etc. 
Fence sensor. An exterior intrusion detection sensor that detects aggressors as they 
attempt to climb over, cut through, or otherwise disturb a fence. 
Fiber optics. A method of data transfer by passing bursts of light through a strand of 
glass or clear plastic. 
Field Assessment Team (FAsT). A small team of pre-identified technical experts that 
conduct an assessment of response needs (not a PDA) immediately following a 
disaster. 
Field of view. The visible area in a video picture. 
First responder. Local police, fire, and emergency medical personnel who first arrive 
on the scene of an incident and take action to save lives, protect property, and meet 
basic human needs.
Flash flood. Follows a situation in which rainfall is so intense and severe and runoff 
so rapid that it precludes recording and relating it to stream stages and other 
information in time to forecast a flood condition. 
Flood. A general and temporary condition of partial or complete inundation of 
normally dry land areas from overflow of inland or tidal waters, unusual or rapid 
accumulation or runoff of surface waters, or mudslides/mudflows caused by 
accumulation of water. 
Forced entry. Entry to a denied area achieved through force to create an opening in 
fence, walls, doors, etc., or to overpower guards. 
Fragment retention film (FRF). A thin, optically clear film applied to glass to 
minimize the spread of glass fragments when the glass is shattered. 
Frame rate. In digital video, a measurement of the rate of change in a series of 
pictures, often measured in frames per second (fps). 
Frangible construction. Building components that are designed to fail to vent blast 
pressures from an enclosure in a controlled manner and direction. 
G
Glare security lighting. Illumination projected from a secure perimeter into the 
surrounding area, making it possible to see potential intruders at a considerable 
distance while making it difficult to observe activities within the secure perimeter. 
Glass-break detector. An intrusion detection sensor that is designed to detect 
breaking glass either through vibration or acoustics. 
Glazing. A material installed in a sash, ventilator, or panes (e.g., glass, plastic, etc., 
including material such as thin granite installed in a curtain wall).
Governors Authorized Representative (GAR). The person empowered by the 
Governor to execute, on behalf of the State, all necessary documents for disaster 
assistance. 
Grid wire sensor. An intrusion detection sensor that uses a grid of wires to cover a wall 
or fence. An alarm is sounded if the wires are cut. 
H
Hand geometry. A biometric technology that is based on characteristics of the human 
hand. 
Hazard. A source of potential danger or adverse condition. 
Hazard mitigation. Any action taken to reduce or eliminate the long-term risk to 
human life and property from hazards. The term is sometimes used in a stricter sense 
to mean cost-effective measures to reduce the potential for damage to a facility or 
facilities from a disaster event. 
Hazardous material (HazMat). Any substance or material that, when involved in an 
accident and released in sufficient quantities, poses a risk to peoples health, safety, 
and/or property. These substances and materials include explosives, radioactive 
materials, flammable liquids or solids, combustible liquids or solids, poisons, 
oxidizers, toxins, and corrosive materials. 
High-hazard areas. Geographic locations that, for planning purposes, have been 
determined through historical experience and vulnerability analysis to be likely to 
experience the effects of a specific hazard (e.g., hurricane, earthquake, hazardous 
materials accident, etc.), resulting in vast property damage and loss of life. 
High-risk target. Any material resource or facility that, because of mission sensitivity, 
ease of access, isolation, and symbolic value, may be an especially attractive or 
accessible terrorist target.
Human-caused hazard. Human-caused hazards are technological hazards and 
terrorism. They are distinct from natural hazards primarily in that they originate 
from human activity. Within the military services, the term threat is typically used for 
human-caused hazard. See definitions of technological hazards and terrorism for 
further information.
Hurricane. A tropical cyclone, formed in the atmosphere over warm ocean areas, in 
which wind speeds reach 74 miles per hour or more and blow in a large spiral around 
a relatively calm center or "eye." Circulation is counter-clockwise in the Northern 
Hemisphere and clockwise in the Southern Hemisphere. 
I
Impact analysis. A management level analysis that identifies the impacts of losing the 
entitys resources. The analysis measures the effect of resource loss and escalating 
losses over time in order to provide the entity with reliable data upon which to base 
decisions on hazard mitigation and continuity planning.
Incident Command System (ICS). A standardized organizational structure used to 
command, control, and coordinate the use of resources and personnel that have 
responded to the scene of an emergency. The concepts and principles for ICS include 
common terminology, modular organization, integrated communication, unified 
command structure, consolidated action plan, manageable span of control, 
designated incident facilities, and comprehensive resource management. 
Insider compromise. A person authorized access to a facility (an insider) 
compromises assets by taking advantage of that accessibility. 
Intercom door/gate station. Part of an intercom system where communication is 
typically initiated, usually located at a door or gate. 
Intercom master station. Part of an intercom system that monitors one or more 
intercom door/gate stations; typically, where initial communication is received. 
Intercom switcher. Part of an intercom system that controls the flow of 
communications between various stations. 
Intercom System. An electronic system that allows simplex, half-duplex, or full-duplex 
audio communications. 
International terrorism. Violent acts or acts dangerous to human life that are a 
violation of the criminal laws of the United States or any state, or that would be a 
criminal violation if committed within the jurisdiction of the United States or any 
state. These acts appear to be intended to intimidate or coerce a civilian population, 
influence the policy of a government by intimidation or coercion, or affect the 
conduct of a government by assassination or kidnapping. International terrorist acts 
occur outside the United States, or transcend national boundaries in terms of the 
means by which they are accomplished, the persons they appear intended to coerce 
or intimidate, or the locale in which their perpetrators operate or seek asylum. 
Intrusion Detection Sensor. A device that initiates alarm signals by sensing the 
stimulus, change, or condition for which it was designed. 
Intrusion Detection System (IDS). The combination of components, including 
sensors, control units, transmission lines, and monitor units, integrated to operate in 
a specified manner. 
Isolated fenced perimeters. Fenced perimeters with 100 feet or more of space outside 
the fence that is clear of obstruction, making approach obvious. 
J
Jersey barrier. A protective concrete barrier initially and still used as a highway 
divider that now also functions as an expedient method for traffic speed control at 
entrance gates and to keep vehicles away from buildings. 
Joint Information Center (JIC). A central point of contact for all news media near the 
scene of a large-scale disaster. News media representatives are kept informed of 
activities and events by Public Information Officers who represent all participating 
federal, state, and local agencies that are collocated at the JIC. 
Joint Information System (JIS). Under the FRP, connection of public affairs 
personnel, decision-makers, and news centers by electronic mail, fax, and telephone 
when a single federal-state-local JIC is not a viable option. 
Joint Interagency Intelligence Support Element (JIISE). An interagency intelligence 
component designed to fuse intelligence information from the various agencies 
participating in a response to a WMD threat or incident within an FBI JOC. The JIISE 
is an expanded version of the investigative/intelligence component that is part of the 
standardized FBI command post structure. The JIISE manages five functions, 
including: security, collections management, current intelligence, exploitation, and 
dissemination.
Joint Operations Center (JOC). Established by the LFA under the operational control 
of the federal OSC, as the focal point for management and direction of on-site 
activities, coordination/establishment of state requirements/priorities, and 
coordination of the overall federal response.
Jurisdiction. Typically counties and cities within a state, but states may elect to define 
differently in order to facilitate their assessment process. 
L
Laminated glass. A flat lite of uniform thickness consisting of two monolithic glass 
plies bonded together with an interlayer material as defined in Specification C1172. 
Many different interlayer materials are used in laminated glass. 
Landscaping. The use of plantings (shrubs and trees), with or without landforms 
and/or large boulders, to act as a perimeter barrier against defined threats. 
Laser card. A card technology that uses a laser reflected off of a card for uniquely 
identifying the card. 
Layers of protection. A traditional approach in security engineering using concentric 
circles extending out from an area to be protected as demarcation points for different 
security strategies. 
Lead Agency. The federal department or agency assigned lead responsibility under 
U.S. law to manage and coordinate the federal response in a specific functional area. 
Lead Federal Agency (LFA). The agency designated by the President to lead and 
coordinate the overall federal response is referred to as the LFA and is determined by 
the type of emergency. In general, an LFA establishes operational structures and 
procedures to assemble and work with agencies providing direct support to the LFA 
in order to provide an initial assessment of the situation, develop an action plan, 
monitor and update operational priorities, and ensure each agency exercises its 
concurrent and distinct authorities under U.S. law and supports the LFA in carrying 
out the Presidents relevant policy. Specific responsibilities of an LFA vary, according 
to the agencys unique statutory authorities.
Level of protection (LOP). The degree to which an asset is protected against injury or 
damage from an attack.
Liaison. An agency official sent to another agency to facilitate interagency 
communications and coordination.
Limited area. A restricted area within close proximity of a security interest. 
Uncontrolled movement may permit access to the item. Escorts and other internal 
restrictions may prevent access to the item. See controlled area and exclusion area.
Line of sight (LOS). Direct observation between two points with the naked eye or 
hand-held optics. 
Line-of-sight sensor. A pair of devices used as an intrusion detection sensor that 
monitor any movement through the field between the sensors.
Line supervision. A data integrity strategy that monitors the communications link for 
connectivity and tampering. In Intrusion Detection System sensors, line supervision 
is often referred to as two-state, three-state, or four-state in respect to the number of 
conditions monitored. The frequency of sampling the link also plays a big part in the 
supervision of the line. 
Local government. Any county, city, village, town, district, or political subdivision of 
any state, and Indian tribe or authorized tribal organization, or Alaska Native village 
or organization, including any rural community or unincorporated town or village or 
any other public entity.
M
Magnetic lock. An electromagnetic lock that unlocks a door when power is removed. 
Magnetic stripe. A card technology that uses a magnetic stripe on the card to encode 
data used for unique identification of the card. 
Mail-bomb delivery. Bombs or incendiary devices delivered to the target in letters or 
packages. 
Man-trap. An access control strategy that uses a pair of interlocking doors to prevent 
tailgating. Only one door can be unlocked at a time. 
Mass care. The actions that are taken to protect evacuees and other disaster victims 
from the effects of the disaster. Activities include providing temporary shelter, food, 
medical care, clothing, and other essential life support needs to those people who 
have been displaced from their homes because of a disaster or threatened disaster. 
Mass notification. Capability to provide real-time information to all building 
occupants or personnel in the immediate vicinity of a building during emergency 
situations.
Microwave motion sensor. An intrusion detection sensor that uses microwave energy 
to sense movement within the sensors field of view. These sensors work similar to 
radar by using the Doppler effect to measure a shift in frequency. 
Military installations. Army, Navy, Air Force, and Marine Corps bases, posts, stations, 
and annexes (both contractor and government operated), hospitals, terminals, and 
other special mission facilities, as well as those used primarily for military purposes. 
Minimum essential infrastructure resource elements. The broad categories of 
resources, all or portions of which constitute the minimal essential infrastructure 
necessary for a department, agency, or organization to conduct its core mission(s). 
Minimum measures. Protective measures that can be applied to all buildings 
regardless of the identified threat. These measures offer defense or detection 
opportunities for minimal cost, facilitate future upgrades, and may deter acts of 
aggression. 
Mitigation. Those actions taken to reduce the exposure to and impact of an attack or 
disaster.
Motion detector. An intrusion detection sensor that changes state based on 
movement in the sensors field of view. 
Moving vehicle bomb. An explosive-laden car or truck driven into or near a building 
and detonated. 
Mutual Aid Agreement. A pre-arranged agreement developed between two or more 
entities to render assistance to the parties of the agreement.
N
Natural hazard. Naturally-occurring events such as floods, earthquakes, tornadoes, 
tsunami, coastal storms, landslides, and wildfires that strike populated areas. A 
natural event is a hazard when it has the potential to harm people or property (FEMA 
386-2, Understanding Your Risks). The risks of natural hazards may be increased or 
decreased as a result of human activity; however, they are not inherently human-
induced. 
Natural protective barriers. Natural protective barriers are mountains and deserts, 
cliffs and ditches, water obstacles, or other terrain features that are difficult to 
traverse. 
Non-exclusive zone. An area around an asset that has controlled entry, but shared or 
less restrictive access than an exclusive zone.
Non-persistent agent. An agent that, upon release, loses its ability to cause casualties 
after 10 to 15 minutes. It has a high evaporation rate, is lighter than air, and will 
disperse rapidly. It is considered to be a short-term hazard; however, in small, 
unventilated areas, the agent will be more persistent.
Nuclear, biological, or chemical weapons. Also called Weapons of Mass Destruction 
(WMD). Weapons that are characterized by their capability to produce mass 
casualties.
Nuclear detonation. An explosion resulting from fission and/or fusion reactions in 
nuclear material, such as that from a nuclear weapon. 
O
On-Scene Coordinator (OSC). The federal official pre-designated by the EPA and U.S. 
Coast Guard to coordinate and direct response and removals under the National Oil 
and Hazardous Substances Pollution Contingency Plan.
Open systems architecture. A term borrowed from the IT industry to claim that 
systems are capable of interfacing with other systems from any vendor, which also 
uses open system architecture. The opposite would be a proprietary system. 
Operator interface. The part of a security management system that provides that user 
interface to humans. 
Organizational areas of control. Controls consist of the policies, procedures, practices, 
and organization structures designed to provide reasonable assurance that business 
objectives will be achieved and that undesired events will be prevented or detected 
and corrected.
P
Passive infrared motion sensor. A device that detects a change in the thermal energy 
pattern caused by a moving intruder and initiates an alarm when the change in 
energy satisfies the detectors alarm-criteria.
Passive vehicle barrier. A vehicle barrier that is permanently deployed and does not 
require response to be effective. 
Patch panel. A concentrated termination point that separates backbone cabling from 
devices cabling for easy maintenance and troubleshooting. 
Perimeter barrier. A fence, wall, vehicle barrier, landform, or line of vegetation 
applied along an exterior perimeter used to obscure vision, hinder personnel access, 
or hinder or prevent vehicle access. 
Persistent agent. An agent that, upon release, retains its casualty-producing effects for 
an extended period of time, usually anywhere from 30 minutes to several days. A 
persistent agent usually has a low evaporation rate and its vapor is heavier than air; 
therefore, its vapor cloud tends to hug the ground. It is considered to be a long-term 
hazard. Although inhalation hazards are still a concern, extreme caution should be 
taken to avoid skin contact as well.
Physical security. The part of security concerned with measures/concepts designed to 
safeguard personnel; to prevent unauthorized access to equipment, installations, 
materiel, and documents; and to safeguard them against espionage, sabotage, 
damage, and theft.
Planter barrier. A passive vehicle barrier, usually constructed of concrete and filled 
with dirt (and flowers for aesthetics). Planters, along with bollards, are the usual 
street furniture used to keep vehicles away from existing buildings. Overall size and 
the depth of installation below grade determine the vehicle stopping capability of the 
individual planter.
Plume. Airborne material spreading from a particular source; the dispersal of 
particles, gases, vapors, and aerosols into the atmosphere.
Polycarbonate glazing. A plastic glazing material with enhanced resistance to 
ballistics or blast effects. 
Predetonation screen. A fence that causes an anti-tank round to detonate or prevents 
it from arming before it reaches its target. 
Preliminary Damage Assessment (PDA). A mechanism used to determine the impact 
and magnitude of damage and the resulting unmet needs of individuals, businesses, 
the public sector, and the community as a whole. Information collected is used by the 
state as a basis for the Governors request for a Presidential declaration, and by FEMA 
to document the recommendation made to the President in response to the 
Governors request. PDAs are made by at least one state and one federal 
representative. A local government representative familiar with the extent and 
location of damage in the community often participates; other state and federal 
agencies and voluntary relief organizations also may be asked to participate, as 
needed. 
Preparedness. Establishing the plans, training, exercises, and resources necessary to 
enhance mitigation of and achieve readiness for response to, and recovery from all 
hazards, disasters, and emergencies, including WMD incidents.
Pressure mat. A mat that generates an alarm when pressure is applied to any part of 
the mats surface, such as when someone steps on the mat. Pressure mats can be used 
to detect an intruder approaching a protected object, or they can be placed by doors 
and windows to detect entry. 
Primary asset. An asset that is the ultimate target for compromise by an aggressor. 
Primary gathering building. Inhabited buildings routinely occupied by 50 or more 
personnel. This designation applies to the entire portion of a building that meets the 
population density requirements for an inhabited building. 
Probability of detection (POD). A measure of an intrusion detection sensors 
performance in detecting an intruder within its detection zone. 
Probability of intercept. The probability that an act of aggression will be detected and 
that a response force will intercept the aggressor before the asset can be 
compromised. 
Progressive collapse. A chain reaction failure of building members to an extent 
disproportionate to the original localized damage. Such damage may result in upper 
floors of a building collapsing onto lower floors.
Protective barriers. Define the physical limits of a site, activity, or area by restricting, 
channeling, or impeding access and forming a continuous obstacle around the 
object.
Protective measures. Elements of a protective system that protect an asset against a 
threat. Protective measures are divided into defensive and detection measures. 
Protective system. An integration of all of the protective measures required to protect 
an asset against the range of threats applicable to the asset. 
Proximity sensor. An intrusion detection sensor that changes state based on the close 
distance or contact of a human to the sensor. These sensors often measure the 
change in capacitance as a human body enters the measured field. 
Public Information Officer (PIO). A federal, state, or local government official 
responsible for preparing and coordinating the dissemination of emergency public 
information. 
R
Radiation. High-energy particles or gamma rays that are emitted by an atom as the 
substance undergoes radioactive decay. Particles can be either charged alpha or beta 
particles or neutral neutron or gamma rays.
Radiation sickness. The symptoms characterizing the sickness known as radiation 
injury, resulting from excessive exposure of the whole body to ionizing radiation. 
Radiological monitoring. The process of locating and measuring radiation by means 
of survey instruments that can detect and measure (as exposure rates) ionizing 
radiation. 
Recovery. The long-term activities beyond the initial crisis period and emergency 
response phase of disaster operations that focus on returning all systems in the 
community to a normal status or to reconstitute these systems to a new condition that 
is less vulnerable. 
Regional Operations Center (ROC). The temporary operations facility for the 
coordination of federal response and recovery activities located at the FEMA Regional 
Office (or Federal Regional Center) and led by the FEMA Regional Director or 
Deputy Director until the DFO becomes operational. After the ERT-A is deployed, the 
ROC performs a support role for federal staff at the disaster scene. 
Report printers. A separate, dedicated printer attached to the Electronic Security 
Systems used for generating reports utilizing information stored by the central 
computer.
Request-to-exit device. Passive infrared motion sensors or push buttons that are used 
to signal an Electronic Entry Control System that egress is imminent or to unlock a 
door. 
Resolution. The level to which video details can be determined in a CCTV scene is 
referred to as resolving ability or resolution. 
Resource Management. Those actions taken by a government to: identify sources and 
obtain resources needed to support disaster response activities; coordinate the supply, 
allocation, distribution, and delivery of resources so that they arrive where and when 
most needed; and maintain accountability for the resources used. 
Response. Executing the plan and resources identified to perform those duties and 
services to preserve and protect life and property as well as provide services to the 
surviving population.
Response force. The people who respond to an act of aggression. Depending on the 
nature of the threat, the response force could consist of guards, special reaction 
teams, military or civilian police, an explosives ordnance disposal team, or a fire 
department. 
Response time. The length of time from the instant an attack is detected to the 
instant a security force arrives on site. 
Restricted area. Any area with access controls that is subject to these special 
restrictions or controls for security reasons. See controlled area, limited area, 
exclusion area, and exclusion zone.
Retinal pattern. A biometric technology that is based on features of the human eye. 
RF data transmission. A communications link using radio frequency to send or 
receive data. 
Risk. The potential for loss of, or damage to, an asset. It is measured based upon the 
value of the asset in relation to the threats and vulnerabilities associated with it.
Rotating drum or rotating plate vehicle barrier. An active vehicle barrier used at vehicle 
entrances to controlled areas based on a drum or plate rotating into the path of the 
vehicle when signaled.
Routinely occupied. For the purposes of these standards, an established or predictable 
pattern of activity within a building that terrorists could recognize and exploit.
RS-232 data. IEEE Recommended Standard 232; a point-to-point serial data protocol 
with a maximum effective distance of 50 feet. 
RS-422 data. IEEE Recommended Standard 422; a point-to-point serial data protocol 
with a maximum effective distance of 4,000 feet. 
RS-485 data. IEEE Recommended Standard 485; a multi-drop serial data protocol with 
a maximum effective distance of 4,000 feet. 
S
Sacrificial roof or wall. Roofs or walls that can be lost in a blast without damage to the 
primary asset.
Safe haven. Secure areas within the interior of the facility. A safe haven should be 
designed such that it requires more time to penetrate by aggressors than it takes for 
the response force to reach the protected area to rescue the occupants. It may be a 
haven from a physical attack or air-isolated haven from CBR contamination.
Scramble keypad. A keypad that uses keys on which the numbers change pattern with 
each use to enhance security by preventing eavesdropping observation of the entered 
numbers. 
Secondary asset. An asset that supports a primary asset and whose compromise would 
indirectly affect the operation of the primary asset. 
Secondary hazard. A threat whose potential would be realized as the result of a 
triggering event that of itself would constitute an emergency (e.g., dam failure might 
be a secondary hazard associated with earthquakes). 
Secure/access mode. The state of an area monitored by an intrusion detection system 
in regards to how alarm conditions are reported. 
Security analysis. The method of studying the nature of and the relationship between 
assets, threats, and vulnerabilities.
Security console. Specialized furniture, racking, and related apparatus used to house 
the security equipment required in a control center. 
Security engineering. The process of identifying practical, risk managed short- and 
long-term solutions to reduce and/or mitigate dynamic manmade hazards by 
integrating multiple factors, including construction, equipment, manpower, and 
procedures.
Security engineering design process. The process through which assets requiring 
protection are identified, the threat to and vulnerability of those assets is determined, 
and a protective system is designed to protect the assets. 
Security Management System database. In a Security Management System, a database 
that is transferred to various nodes or panels throughout the system for faster data 
processing and protection against communications link downtime. 
Security Management System distributed processing. In a Security Management 
System, a method of data processing at various nodes or panels throughout the system 
for faster data processing and protection against communications links downtime. 
Segregation of duties. Policies, procedures, and an organizational structure 
established so that one individual cannot control key aspects of physical and/or 
computer-related operations and thereby conduct unauthorized actions or gain 
unauthorized access to minimum essential infrastructure resource elements. 
Semi-isolated fenced perimeters. Fence lines where approach areas are clear of 
obstruction for 60 to 100 feet outside of the fence and where the general public or 
other personnel seldom have reason to be in the area. 
Senior FEMA Official (SFO). The official appointed by the Director of FEMA, or his 
representative, that is responsible for deploying to the JOC to serve as the senior 
interagency consequence management representative on the Command Group, and 
to manage and coordinate activities taken by the Consequence Management Group.
Serial interface. An integration strategy for data transfer where components are 
connected in series. 
Shielded wire. Wire with a conductive wrap used to mitigate electromagnetic 
emanations. 
Situational crime prevention. A crime prevention strategy based on reducing the 
opportunities for crime by increasing the effort required to commit a crime, 
increasing the risks associated with committing the crime, and reducing the target 
appeal or vulnerability (whether property or person). This opportunity reduction is 
achieved by management and use policies such as procedures and training, as well as 
physical approaches such as alteration of the built environment.
Smart card. A newer card technology that allows data to be written, stored, and read 
on a card typically used for identification and/or access. 
Software level integration. An integration strategy that uses software to interface 
systems. An example of this would be digital video displayed in the same computer 
application window and linked to events of a security management system.  
Specific threat. Known or postulated aggressor activity focused on targeting a 
particular asset.
Stand-off distance. A distance maintained between a building or portion thereof and 
the potential location for an explosive detonation or other threat.
Stand-off weapons. Weapons such as anti-tank weapons and mortars that are 
launched from a distance at a target.
State Coordinating Officer (SCO). The person appointed by the Governor to 
coordinate state, commonwealth, or territorial response and recovery activities with 
FRP-related activities of the Federal Government, in cooperation with the FCO. 
State Liaison. A FEMA official assigned to a particular state, who handles initial 
coordination with the state in the early stages of an emergency. 
Stationary vehicle bomb. An explosive-laden car or truck stopped or parked near a 
building. 
Storm surge. A dome of sea water created by the strong winds and low barometric 
pressure in a hurricane that causes severe coastal flooding as the hurricane strikes 
land. 
Strain sensitive cable. Strain sensitive cables are transducers that are uniformly 
sensitive along their entire length and generate an analog voltage when subjected to 
mechanical distortions or stress resulting from fence motion. They are typically 
attached to a chain-link fence about halfway between the bottom and top of the fence 
fabric with plastic ties. 
Structural protective barriers. Manmade devices (e.g., fences, walls, floors, roofs, grills, 
bars, roadblocks, signs, or other construction) used to restrict, channel, or impede 
access. 
Superstructure. The supporting elements of a building above the foundation.
Supplies-bomb delivery. Bombs or incendiary devices concealed and delivered to 
supply or material handling points such as loading docks. 
System events. Events that occur normally in the operation of a security management 
system. Examples include access control operations and changes of state in intrusion 
detection sensors. 
System software. Controls that limit and monitor access to the powerful programs 
and sensitive files that control the computer hardware and secure applications 
supported by the system. 
T
Tactics. The specific methods of achieving the aggressors goals to injure personnel, 
destroy assets, or steal materiel or information. 
Tamper switch. Intrusion detection sensor that monitors an equipment enclosure for 
breach. 
Tangle-foot wire. Barbed wire or tape suspended on short metal or wooden pickets 
outside a perimeter fence to create an obstacle to approach. 
Taut wire sensor. An intrusion detection sensor utilizing a column of uniformly 
spaced horizontal wires, securely anchored at each end and stretched taut. Each wire 
is attached to a sensor to indicate movement of the wire. 
Technical assistance. The provisioning of direct assistance to states and local 
jurisdictions to improve capabilities for program development, planning, and 
operational performances related to responses to WMD terrorist incidents. 
Technological hazards. Incidents that can arise from human activities such as 
manufacture, transportation, storage, and use of hazardous materials. For the sake of 
simplicity, it is assumed that technological emergencies are accidental and that their 
consequences are unintended.
TEMPEST. An unclassified short name referring to investigations and studies of 
compromising emanations. It is sometimes used synonymously for the term 
"compromising emanations" (e.g., TEMPEST tests, TEMPEST inspections).  
Terrorism. The unlawful use of force and violence against persons or property to 
intimidate or coerce a government, the civilian population, or any segment thereof, 
in furtherance of political or social objectives.  
Thermally tempered glass (TTG). Glass that is heat-treated to have a higher tensile 
strength and resistance to blast pressures, although with a greater susceptibility to 
airborne debris.  
Threat. Any indication, circumstance, or event with the potential to cause loss of, or 
damage to an asset. 
Threat analysis. A continual process of compiling and examining all available 
information concerning potential threats and human-caused hazards. A common 
method to evaluate terrorist groups is to review the factors of existence, capability, 
intentions, history, and targeting. 
Time/date stamp. Data inserted into a CCTV video signal with the time and date of 
the video as it was created. 
TNT equivalent weight. The weight of TNT (trinitrotoluene) that has an equivalent 
energetic output to that of a different weight of another explosive compound.
Tornado. A local atmospheric storm, generally of short duration, formed by winds 
rotating at very high speeds, usually in a counter-clockwise direction. The vortex, up 
to several hundred yards wide, is visible to the observer as a whirlpool-like column of 
winds rotating about a hollow cavity or funnel. Winds may reach 300 miles per hour 
or higher. 
Toxic-free area. An area within a facility in which the air supply is free of toxic 
chemical or biological agents.  
Toxicity. A measure of the harmful effects produced by a given amount of a toxin on a 
living organism. 
Triple-standard concertina (TSC) wire. This type of fence uses three rolls of stacked 
concertina. One roll will be stacked on top of two other rolls that run parallel to each 
other while resting on the ground, forming a pyramid. 
Tsunami. Sea waves produced by an undersea earthquake. Such sea waves can reach a 
height of 80 feet and can devastate coastal cities and low-lying coastal areas. 
Twisted pair wire. Wire that uses pairs of wires twisted together to mitigate 
electromagnetic interference. 
Two-person rule. A security strategy that requires two people to be present in or gain 
access to a secured area to prevent unobserved access by any individual. 
U
Unobstructed space. Space around an inhabited building without obstruction large 
enough to conceal explosive devices 150 mm (6 inches) or greater in height.
Unshielded wire. Wire that does not have a conductive wrap. 
V
Vault. A reinforced room for securing items. 
Vertical rod. Typical door hardware often used with a crash bar to lock a door by 
inserting rods vertically from the door into the doorframe. 
Vibration sensor. An intrusion detection sensor that changes state when vibration is 
present. 
Video intercom system. An intercom system that also incorporates a small CCTV 
system for verification. 
Video motion detection. Motion detection technology that looks for changes in the 
pixels of a video image.
Video multiplexer. A device used to connect multiple video signals to a single location 
for viewing and/or recording.
Visual displays. A display or monitor used to inform the operator visually of the status 
of the electronic security system.  
Visual surveillance. The aggressor uses ocular and photographic devices (such as 
binoculars and cameras with telephoto lenses) to monitor facility or installation 
operations or to see assets. 
Voice recognition. A biometric technology that is based on nuances of the human 
voice. 
Volumetric motion sensor. An interior intrusion detection sensor that is designed to 
sense aggressor motion within a protected space. 
Vulnerability. Any weakness that can be exploited by an aggressor or, in a nonterrorist 
threat environment, make an asset susceptible to hazard damage.
W
Warning. The alerting of emergency response personnel and the public to the threat 
of extraordinary danger and the related effects that specific hazards may cause. 
Watch. Indication in a defined area that conditions are favorable for the specified 
type of severe weather (e.g., flash flood watch, severe thunderstorm watch, tornado 
watch, tropical storm watch). 
Waterborne contamination. Chemical, biological, or radiological agent introduced 
into and fouling a water supply. 
Weapons-grade material. Nuclear material considered most suitable for a nuclear 
weapon. It usually connotes uranium enriched to above 90 percent uranium-235 or 
plutonium with greater than about 90 percent plutonium-239.
Weapons of Mass Destruction (WMD). Any device, material, or substance used in a 
manner, in a quantity or type, or under circumstances showing an intent to cause 
death or serious injury to persons, or significant damage to property. An explosive, 
incendiary, or poison gas, bomb, grenade, rocket having a propellant charge of more 
than 4 ounces, or a missile having an explosive incendiary charge of more than 0.25 
ounce, or mine or device similar to the above; poison gas; weapon involving a disease 
organism; or weapon that is designed to release radiation or radioactivity at a level 
dangerous to human life. 
Weigand protocol. A security industry standard data protocol for card readers.
Z
Zoom. The ability of a CCTV camera to close and focus or open and widen the field of 
view




CHEMICAL, BIOLOLOGICAL, AND RADIOLOGICAL GLOSSARY    


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CHEMICAL, BIOLOLOGICAL, AND RADIOLOGICAL GLOSSAR


CHEMICAL, BIOLOLOGICAL, AND RADIOLOGICAL GLOSSAR


CHEMICAL, BIOLOLOGICAL, AND RADIOLOGICAL GLOSSAR


This appendix contains some CBR terms that do not actually appear in this manual. 
They have been included to present a comprehensive list that pertains to this series of 
publications.
CHEMICAL TERMS
A
Acetylcholinesterase. An enzyme that hydrolyzes the neurotransmitter acetylcholine. 
The action of this enzyme is inhibited by nerve agents.
Aerosol. Fine liquid or solid particles suspended in a gas (e.g., fog or smoke).
Atropine. A compound used as an antidote for nerve agents.
C
Casualty (toxic) agents. Produce incapacitation, serious injury, or death, and can be 
used to incapacitate or kill victims. They are the blister, blood, choking, and nerve 
agents.
Blister agents. Substances that cause blistering of the skin. Exposure is 
through liquid or vapor contact with any exposed tissue (eyes, skin, lungs). 
Examples are distilled mustard (HD), nitrogen mustard (HN), lewisite (L), 
mustard/lewisite (HL), and phenodichloroarsine (PD).
Blood agents. Substances that injure a person by interfering with cell 
respiration (the exchange of oxygen and carbon dioxide between blood and 
tissues). Examples are arsine (SA), cyanogens chloride (CK), hydrogen 
chloride (HCl), and hydrogen cyanide (AC).
Choking/lung/pulmonary agents. Substances that cause physical injury to the 
lungs. Exposure is through inhalation. In extreme cases, membranes swell 
and lungs become filled with liquid. Death results from lack of oxygen; hence, 
the victim is "choked." Examples are chlorine (CL), diphosgene (DP), cyanide 
(KCN), nitrogen oxide (NO), perfluororisobutylene (PHIB), phosgene (CG), 
red phosphorous (RP), sulfur trioxide-chlorosulfonic acid (FS), Teflon and 
PHIB, titanium tetrachloride (FM), and zinc oxide (HC).
Nerve agents. Substances that interfere with the central nervous system. 
Exposure is primarily through contact with the liquid (skin and eyes) and 
secondarily through inhalation of the vapor. Three distinct symptoms 
associated with nerve agents are:  pin-point pupils, an extreme headache, and 
severe tightness in the chest. See also G-series and V-series nerve agents.
Chemical agents. Substances that are intended for use in military operations to kill, 
seriously injure, or incapacitate people through its physiological effects. Excluded 
from consideration are riot control agents, and smoke and flame materials. The 
agent may appear as a vapor, aerosol, or liquid; it can be either a casualty/toxic agent 
or an incapacitating agent.
Cutaneous. Pertaining to the skin.
D 
Decontamination. The process of making any person, object, or area safe by 
absorbing, destroying, neutralizing, making harmless, or removing the hazardous 
material.

G
G-series nerve agents. Chemical agents of moderate to high toxicity developed in the 
1930s. Examples are tabun (GA), sarin (GB), soman (GD), phosphonofluoridic acid, 
ethyl-, 1-methylethyl ester (GE), and cyclohexyl sarin (GF).
I
Incapacitating agents. Produce temporary physiological and/or mental effects via 
action on the central nervous system. Effects may persist for hours or days, but victims 
usually do not require medical treatment; however, such treatment speeds recovery.
Vomiting agents. Produce nausea and vomiting effects; can also cause 
coughing, sneezing, pain in the nose and throat, nasal discharge, and tears. 
Examples are adamsite (DM), diphenylchloroarsine (DA), and 
diphenylcyanoarsine (DC).
Tear (riot control) agents. Produce irritating or disabling effects that rapidly 
disappear within minutes after exposure ceases. Examples are 
bromobenzylcyanide (CA), chloroacetophenone (CN or commercially known 
as Mace), chloropicrin (PS), CNB (CN in benzene and carbon tetrachloride), 
CNC (CN in chloroform), CNS (CN and chloropicrin in chloroform, CR 
(dibenz-(b,f)-1,4-oxazepine, a tear gas), CS (tear gas), and Capsaicin (pepper 
spray).
Central nervous system depressants. Compounds that have the predominant 
effect of depressing or blocking the activity of the central nervous system. The 
primary mental effects include the disruption of the ability to think, sedation, 
and lack of motivation.
Central nervous system stimulants. Compounds that have the predominant 
effect of flooding the brain with too much information. The primary mental 
effect is loss of concentration, causing indecisiveness and the inability to act 
in a sustained, purposeful manner.
Examples of the depressants and stimulants include agent 15 (suspected Iraqi 
BZ), BZ (3-quinulidinyle benzilate), canniboids, fentanyls, LSD (lysergic acid 
diethylamide), and phenothiazines.
Industrial agents. Chemicals developed or manufactured for use in industrial 
operations or research by industry, government, or academia. These chemicals are 
not primarily manufactured for the specific purpose of producing human casualties 
or rendering equipment, facilities, or areas dangerous for use by man. Hydrogen 
cyanide, cyanogen chloride, phosgene, chloropicrin, and many herbicides and 
pesticides are industrial chemicals that also can be chemical agents.
L
Liquid agents. Chemical agents that appear to be an oily film or droplets. The color 
ranges from clear to brownish amber.
N
Nonpersistent agents. Agents that, upon release, lose the ability to cause casualties 
after 10 to 15 minutes. They have a high evaporation rate and are lighter than air and 
will disperse rapidly. They are considered to be short-term hazards; however, in small 
unventilated areas, these agents will be more persistent.
O
Organophosphorous compound. A compound containing the elements phosphorus 
and carbon, whose physiological effects include inhibition of acetylcholinesterase. 
Many pesticides (malathione and parathion) and virtually all nerve agents are 
organophosphorous compounds.
P
Percutaneous agents. Agents that are able to be absorbed by the body through the 
skin.
Persistent agents. Agents that, upon release, retain their casualty-producing effects for 
an extended period of time, usually anywhere from 30 minutes to several days. A 
persistent agent usually has a low evaporation rate and its vapor is heavier than air. 
Therefore, its vapor cloud tends to hug the ground. They are considered to be long-
term hazards. Although inhalation hazards are still a concern, extreme caution 
should be taken to avoid skin contact as well.
Protection. Any means by which an individual protects his or her body. Measures 
include masks, self-contained breathing apparatuses, clothing, structures such as 
buildings, and vehicles.
V
V-series nerve agents. Chemical agents of moderate to high toxicity developed in the 
1950s. They are generally persistent. Examples are VE (phosphonothioic acid, ethyl-, 
S-[2-(diethylamino)ethyl] O-ethylester), VG (phosphorothioic acid, S-[2-
(diethylamino)ethyl] O, O-diethyl ester), VM (phosphonothioic acid, methyl-, S-[2-
(diethylamino) ethyl] O-ethyl ester), VS (phosphonothioic acid, ethyl, S-[2-[bis(1-
methylethyl)amino] ethyl] O-ethyl ester), and VX (phosphonothioic acid, methyl-, S-
[2-[bis(1-methylethyl)amino]ethyl] O-ethyl ester).
Vapor agents. A gaseous form of a chemical agent. If heavier than air, the cloud will 
be close to the ground. If lighter than air, the cloud will rise and disperse more 
quickly.
Volatility. A measure of how readily a substance will vaporize.
Placards Associated with Chemical Incidents
BIOLOGICAL TERMS
A
Aerosol. Fine liquid or solid particles suspended in a gas (e.g., fog or smoke).
Antibiotic. A substance that inhibits the growth of or kills microorganisms.
Antisera. The liquid part of blood containing antibodies that react against disease-
causing agents such as those used in biological warfare.
B
Bacteria. Single-celled organisms that multiply by cell division and that can cause 
disease in humans, plants, or animals.
Biochemicals. The chemicals that make up or are produced by living things.
Biological warfare. The intentional use of biological agents as weapons to kill or 
injure humans, animals, or plants, or to damage equipment.
Biological warfare agents. Living organisms or the materials derived from them that 
cause disease in or harm to humans, animals, or plants, or cause deterioration of 
material. Biological agents may be used as liquid droplets, aerosols, or dry powders.
Bioregulators. Biochemicals that regulate bodily functions. Bioregulators that are 
produced by the body are termed "endogenous." Some of these same bioregulators 
can be chemically synthesized.

C
Causative agents. The organism or toxin that is responsible for causing a specific 
disease or harmful effect.
Contagious. Capable of being transmitted from one person to another.
Culture. A population of microorganisms grown in a medium.
D
Decontamination. The process of making people, objects, or areas safe by absorbing, 
destroying, neutralizing, making harmless, or removing the hazardous material.
F
Fungi. Any of a group of plants mainly characterized by the absence of chlorophyll, 
the green colored compound found in other plants. Fungi range from microscopic 
single-celled plants (such as molds and mildews) to large plants (such as 
mushrooms).
H
Host. An animal or plant that harbors or nourishes another organism.
I
Incapacitating agents. Agents that produce physical or psychological effects, or both, 
that may persist for hours or days after exposure, rendering victims incapable of 
performing normal physical and mental tasks.
Infectious agents. Biological agents capable of causing disease in a susceptible host.
Infectivity. (1) The ability of an organism to spread. (2) The number of organisms 
required to cause an infection to secondary hosts. (3) The capability of an organism 
to spread out from the site of infection and cause disease in the host organism. 
Infectivity also can be viewed as the number of organisms required to cause an 
infection.
L
Line-source delivery system. A delivery system in which the biological agent is 
dispersed from a moving ground or air vehicle in a line perpendicular to the 
direction of the prevailing wind. (See also "point-source delivery system.")
M
Microorganism. Any organism, such as bacteria, viruses, and some fungi, that can be 
seen only with a microscope.
Mycotoxin. A toxin produced by fungi.
N
Nebulizer. A device for producing a fine spray or aerosol.
O
Organism. Any individual living thing, whether animal or plant.
P
Parasite. Any organism that lives in or on another organism without providing 
benefit in return.
Pathogen. Any organism (usually living), such as bacteria, fungi, and viruses, capable 
of producing serious disease or death.
Pathogenic agents. Biological agents capable of causing serious disease.
Point-source delivery system. A delivery system in which the biological agent is 
dispersed from a stationary position. This delivery method results in coverage over a 
smaller area than with the line-source system. See also line-source delivery system.
R
Route of exposure (entry). The path by which a person comes into contact with an 
agent or organism (e.g., through breathing, digestion, or skin contact).
S
Single-cell protein. Protein-rich material obtained from cultured algae, fungi, protein, 
and bacteria, and often used as food or animal feed.
Spore. A reproductive form some microorganisms can take to become resistant to 
environmental conditions, such as extreme heat or cold, while in a "resting stage."
T
Toxicity. A measure of the harmful effect produced by a given amount of a toxin on a 
living organism. The relative toxicity of an agent can be expressed in milligrams of 
toxin needed per kilogram of body weight to kill experimental animals.
Toxins. Poisonous substances produced by living organisms.
V
Vaccine. A preparation of killed or weakened microorganism products used to 
artificially induce immunity against a disease.
Vector. An agent, such as an insect or rat, capable of transferring a pathogen from 
one organism to another.
Venom. A poison produced in the glands of some animals (e.g., snakes, scorpions, or 
bees).
Virus. An infectious microorganism that exists as a particle rather than as a complete 
cell. Particle sizes range from 20 to 400 nanometers (one-billionth of a meter). 
Viruses are not capable of reproducing outside of a host cell. 
Placards Associated with Biological Incidents


RADIOLOGICAL TERMS
A
Acute radiation syndrome. Consists of three levels of effects: hernatopoletic (blood 
cells, most sensitive); gastrointestinal (GI cells, very sensitive); and central nervous 
system (brain/muscle cells, insensitive). The initial signs and symptoms are nausea, 
vomiting, fatigue, and loss of appetite. Below about 200 rems, these symptoms may be 
the only indication of radiation exposure.
Alpha particles (_). Alpha particles have a very short range in air and a very low ability 
to penetrate other materials, but also have a strong ability to ionize materials. Alpha 
particles are unable to penetrate even the thin layer of dead cells of human skin and 
consequently are not an external radiation hazard. Alpha-emitting nuclides inside 
the body as a result of inhalation or ingestion are a considerable internal radiation 
hazard.
B
Beta particles (_). High-energy electrons emitted from the nucleus of an atom during 
radioactive decay. They normally can be stopped by the skin or a very thin sheet of 
metal.
C
Cesium-137 (Cs-137). A strong gamma ray source and can contaminate property, 
entailing extensive cleanup. It is commonly used in industrial measurement gauges 
and for irradiation of material. Its half-life is 30.2 years.
Cobalt-60 (Co-60). A strong gamma ray source, and is extensively used as a 
radiotherapeutic for treating cancer, food and material irradiation, gamma 
radiography, and industrial measurement gauges. Its half-life is 5.27 years.
Curie (Ci). A unit of radioactive decay rate defined as 3.7 x 1010 disintegrations per 
second.
D
Decay. The process by which an unstable element is changed to another isotope or 
another element by the spontaneous emission of radiation from its nucleus. This 
process can be measured by using radiation detectors such as Geiger counters.
Decontamination. The process of making people, objects, or areas safe by absorbing, 
destroying, neutralizing, making harmless, or removing the hazardous material.
Dose. A general term for the amount of radiation absorbed over a period of time.
Dosimeter. A portable instrument for measuring and registering the total 
accumulated dose to ionizing radiation.
G
Gamma ray (_). A high-energy photon emitted from the nucleus of atoms; similar to 
an x-ray. It can penetrate deeply into body tissue and many materials. Cobalt-60 and 
Cesium-137 are both strong gamma-emitters. Shielding against gamma radiation re-
quires thick layers of dense materials, such as lead. Gamma rays are potentially lethal 
to humans.
H
Half-life. The amount of time needed for half of the atoms of a radioactive material to 
decay.

Highly enriched uranium (HEU). Uranium that is enriched to above 20 percent 
Uranium-235 (U-235). Weapons-grade HEU is enriched to above 90 percent in U-235.
I
Ionize. To split off one or more electrons from an atom, thus leaving it with a positive 
electric charge. The electrons usually attach to one of the atoms or molecules, giving 
them a negative charge.
Iridium-192. A gamma ray emitting radioisotope used for gamma radiography. Its half-
life is 73.83 days.
Isotope. A specific element always has the same number of protons in the nucleus. 
That same element may, however, appear in forms that have different numbers of 
neutrons in the nucleus. These different forms are referred to as "isotopes" of the 
element; for example, deuterium (2H) and tritium (3H) are isotopes of ordinary 
hydrogen (H).
L
Lethal dose (50/30). The dose of radiation expected to cause death within 30 days to 
50 percent of those exposed without medical treatment. The generally accepted range 
is from 400-500 rem received over a short period of time.
N
Nuclear reactor. A device in which a controlled, self-sustaining nuclear chain 
reaction can be maintained with the use of cooling to remove generated heat.
P
Plutonium-239 (Pu-239). A metallic element used for nuclear weapons. Its half-life is 
24,110 years.
R
Rad. A unit of absorbed dose of radiation defined as deposition of 100 ergs of energy 
per gram of tissue. A rad amounts to approximately one ionization per cubic micron.
Radiation. High energy alpha or beta particles or gamma rays that are emitted by an 
atom as the substance undergoes radioactive decay.
Radiation sickness. Symptoms resulting from excessive exposure to radiation of the 
body.
Radioactive waste. Disposable, radioactive materials resulting from nuclear 
operations. Wastes are generally classified into two categories, high-level and low-
level.
Radiological Dispersal Device (RDD). A device (weapon or equipment), other than a 
nuclear explosive device, designed to disseminate radioactive material in order to 
cause destruction, damage, or injury by means of the radiation produced by the decay 
of such material.
Radioluminescence. The luminescence produced by particles emitted during 
radioactive decay.
Roentgen Equivalent Man (REM or rem). A unit of absorbed dose that takes into 
account the relative effectiveness of radiation that harms human health.
S
Shielding. Materials (lead, concrete, etc.) used to block or attenuate radiation for 
protection of equipment, materials, or people.
Special Nuclear Material (SNM). Plutonium and uranium enriched in the isotopes 
Uranium-233 or Uranium-235.
U
Uranium 235 (U-235). Naturally-occurring U-235 is found at 0.72 percent enrichment. 
U-235 is used as a reactor fuel or for weapons; however, weapons typically use U-235 
enriched to 90 percent. Its half-life is 7.04 x 108 years.
X
X-ray. An invisible, highly penetrating electromagnetic radiation of much shorter 
wavelength (higher frequency) than visible light. Very similar to gamma rays.
Placards Associated with Radiological Incidents


Gases  Toxic (Corrosive


Gases  Toxic and/or Corrosiv


Substances  Toxic (Non-Combustible


Infectious Substance


Radioactive Material


The following web sites are available for further clarification or for terms not used in 
this manual:
Chemical, Biological, Radiological (CBR) [Formerly NBC (Nuclear, Biological, 
Chemical]
http://www.nbc-med.org/SiteContent/glossary.asp?B
http://www.nbcprotect.com/new/glossary.ht




C-


CHEMICAL, BIOLOLOGICAL, AND RADIOLOGICAL GLOSSAR


CHEMICAL WARFARE AGENT CHARACTERISIC


Note:
Tables reduced for review purposes only.  These tables will be appear as 11x17 foldout pages in the printed publication


SELECTED BIOLOGICAL AGENT CHARACTERISIC


This appendix contains some CBR terms that do not actually appear in this manual. 
They have been included to present a comprehensive list that pertains to this series of 
publications.
CHEMICAL TERMS
A
Acetylcholinesterase. An enzyme that hydrolyzes the neurotransmitter acetylcholine. 
The action of this enzyme is inhibited by nerve agents.
Aerosol. Fine liquid or solid particles suspended in a gas (e.g., fog or smoke).
Atropine. A compound used as an antidote for nerve agents.
C
Casualty (toxic) agents. Produce incapacitation, serious injury, or death, and can be 
used to incapacitate or kill victims. They are the blister, blood, choking, and nerve 
agents.
Blister agents. Substances that cause blistering of the skin. Exposure is 
through liquid or vapor contact with any exposed tissue (eyes, skin, lungs). 
Examples are distilled mustard (HD), nitrogen mustard (HN), lewisite (L), 
mustard/lewisite (HL), and phenodichloroarsine (PD).
Blood agents. Substances that injure a person by interfering with cell 
respiration (the exchange of oxygen and carbon dioxide between blood and 
tissues). Examples are arsine (SA), cyanogens chloride (CK), hydrogen 
chloride (HCl), and hydrogen cyanide (AC).
Choking/lung/pulmonary agents. Substances that cause physical injury to the 
lungs. Exposure is through inhalation. In extreme cases, membranes swell 
and




ELECTRONIC SECURITY SYSTEMS     





An overall site-security system is composed of three major subelements: 
detection, delay, and response. The detection subelement includes intrusion 
detection, assessment, and entry control. The purpose of this appendix is to 
introduce the basic concepts of site security systems, including the use of Electronic 
Security Systems (ESSs), boundary-penetration sensors, volumetric motion sensors, 
exterior intrusion detection sensors, microwave sensors, infrared sensors, video 
motion sensors, electronic entry control, and monitoring designated restricted areas. 
USE OF ESS
An ESS is an integrated system that encompasses interior and exterior sensors; closed 
circuit television (CCTV) systems for assessing alarm conditions; Electronic Entry 
Control Systems (EECSs); data-transmission media (DTM); and alarm reporting 
systems for monitoring, controlling, and displaying various alarm and system 
information. Interior and exterior sensors and their associated communication and 
display subsystems are collectively called IDSs.
An ESS is used to provide early warning of an intruder. This system consists of 
hardware and software elements operated by trained security personnel.
A system is configured to provide one or more layers of detection around an asset. 
Each layer is made up of a series of contiguous detection zones designed to isolate 
the asset and to control the entry and exit of authorized personnel and materials.
General ESS Description
An ESS consists of sensors interfaced with electronic entry control devices, CCTV, 
alarm reporting displays (both visual and audible), and security lighting. The 
situation is assessed by sending guards to the alarm point or by using CCTV. Alarm 
reporting devices and video monitors are located in the security center. The assets 
importance will determine whether multiple or redundant security centers are 
required and, ultimately, the required sophistication of all elements in the ESS. 
Digital and analog data are transmitted from local (field) interior and exterior 
locations to the security center for processing. Reliability and accuracy are important 
functional requirements of the data-transmission system.
ESS Design Considerations
A facility may require interior and exterior ESS elements, depending on the level of 
protection required. The applicable regulations, threat, and design criteria will 
define the ESSs general requirements. For an existing ESS, hardware and software 
may need to be supplemented, upgraded, or completely replaced. A site layout (in 
which all assets are identified and located) is required. It is a useful design tool for 
such tasks as configuring the DTM.
The exterior and interior IDSs should be configured as layers of unbroken rings 
concentrically surrounding the asset. These rings should correspond to defensive 
layers that constitute the delay system. The first detection layer is located at the 
outermost defensive layer necessary to provide the required delay. Detection layers 
can be on a defensive layer, in the area between two defensive layers, or on the asset 
itself, depending on the delay required. For example, if a wall of an interior room 
provides sufficient delay for effective response to aggression, detection layers could be 
between the facility exterior and interior-room wall or on the interior-room wall. 
They would detect the intruder before penetration of the interior wall is possible.
PERIMETER LAYOUT AND ZONING SENSORS
A protected areas perimeter is usually defined by an enclosing wall or fence or a 
natural barrier such as water. For exterior sensors to be effective, the perimeter 
around which they are to be deployed must be precisely defined. In most applications, 
a dual chain-link-fence configuration will be established around the perimeter (see 
Chapter 2.4.1 for additional information). Typically, fences should be between 30 and 
50 feet apart; as the distance increases, it is harder for an intruder to bridge the 
fences. If fence separation is less than 30 feet, some microwave and ported coax 
sensors cannot be used. The area between fences (called the controlled area or 
isolation zone) may need to be cleared of vegetation and graded, depending on the 
type of sensor used. Proper drainage is required to preclude standing water and to 
prevent the formation of gullies caused by running water after a heavy rain or melting 
snow. Cleared areas are required inside and outside of the controlled area. These 
areas enhance routine observation, as well as sensor-alarm assessment, and minimize 
the protective cover available to a would-be intruder.
After the perimeter has been defined, the next step is to divide it into specific 
detection zones. The length of each detection zone is determined by evaluating the 
contour, the existing terrain, and the operational activities along the perimeter. 
Detection zones should be long and straight to minimize the number of sensors or 
cameras necessary and to aid guard assessment if cameras are not used. It may be 
more economical to straighten an existing fence line than to create numerous 
detection zones in accommodating a crooked fence line. If the perimeter is hilly and 
line of sight (LOS) sensors or CCTV assessment are used, the length of individual 
detection zones will be commensurate with sensor limitations. Entry points for 
personnel and vehicles must be configured as independent zones. This enables 
deactivation of the sensors in these zones; that is, placing them in the access mode 
during customary working hours (assuming the entry points are manned) without 
having to deactivate adjacent areas.
The specific length of individual zones can vary around the perimeter. Although 
specific manufacturers may advertise maximum zone lengths exceeding 1,000 feet, it 
is not practical to exceed a zone length of 300 feet. If the zone is longer, it will be 
difficult for an operator using CCTV assessment or for the response force to identify 
the location of an intrusion or the cause of a false alarm.
When establishing zones using multiple sensors, the designer should establish 
coincident zones where the length and location of each individual sensor will be 
identical for all sensors within a given zone. If an alarm occurs in a specific zone, the 
operator can readily determine its approximate location by referring to a map of the 
perimeter. This also minimizes the number of CCTV cameras required for assessment 
and simplifies the interface between the alarm-annunciation system and the CCTV 
switching system.
BOUNDARY-PENETRATION SENSORS
Boundary-penetration sensors are designed to detect penetration or attempted 
penetration through perimeter barriers. These barriers include walls, ceilings, duct 
openings, doors, and windows. 
_		 Structural-vibration sensors. Structural-vibration sensors detect low-frequency 
energy generated in an attempted penetration of a physical barrier (such as a wall 
or a ceiling) by hammering, drilling, cutting, detonating explosives, or employing 
other forcible methods of entry. A piezoelectric transducer senses mechanical 
energy and converts it into electrical signals proportional in magnitude to the 
vibrations. 
_		 Glass-breakage sensors. Glass-breakage sensors detect the breaking of glass. 
The noise from breaking glass consists of frequencies in both the audible and 
ultrasonic range. Glass-breakage sensors use microphone transducers to detect 
the glass breakage. The sensors are designed to respond to specific frequencies 
only, thus minimizing such false alarms as may be caused by banging on the glass.
_		 Passive ultrasonic sensors. Passive ultrasonic sensors detect acoustical energy 
in the ultrasonic frequency range, typically between 20 and 30 kilohertz (kHz). 
They are used to detect an attempted penetration through rigid barriers (such as 
metal or masonry walls, ceilings, and floors). They also detect penetration 
through windows and vents covered by metal grilles, shutters, or bars if these 
openings are properly sealed against outside sounds.
_		 Balanced magnetic switches. Balanced magnetic switches (BMSs) are typically 
used to detect the opening of a door. These sensors can also be used on windows, 
hatches, gates, or other structural devices that can be opened to gain entry. When 
using a BMS, mount the switch mechanism on the doorframe and the actuating 
magnet on the door. Typically, the BMS has a three-position reed switch and an 
additional magnet (called the bias magnet) located adjacent to the switch. When 
the door is closed, the reed switch is held in the balanced or center position by 
interacting magnetic fields. If the door is opened or an external magnet is 
brought near the sensor in an attempt to defeat it, the switch becomes unbalanced 
and generates an alarm. A BMS must be mounted so that the magnet receives 
maximum movement when the door or window is opened. 
_		 Grid wire sensors.  The grid wire sensor consists of a continuous electrical 
wire arranged in a grid pattern. The wire maintains an electrical current. An 
alarm is generated when the wire is broken. The sensor detects forced entry 
through walls, floors, ceilings, doors, windows, and other barriers. An enamel-
coated number 24 or 26 American wire gauge (AWG) solid-copper wire typically 
forms the grid. The grids maximum size is determined by the spacing between 
the wires, the wires resistance, and the electrical characteristics of the source 
providing the current. The grid wire can be installed directly on the barrier, in a 
grille or screen that is mounted on the barrier, or over an opening that requires 
protection. 
VOLUMETRIC MOTION SENSORS
Volumetric motion sensors are designed to detect intruder motion within the 
interior of a protected volume. Volumetric sensors may be active or passive. Active 
sensors (such as microwave) fill the volume to be protected with an energy pattern 
and recognize a disturbance in the pattern when anything moves within the de-
tection zone. Whereas active sensors generate their own energy pattern to detect an 
intruder, passive sensors (such as infrared (IR)) detect energy generated by an 
intruder. Some sensors, known as dual technology sensors, use a combination of two 
different technologies, usually one active and one passive, within the same unit. If 
CCTV assessment or surveillance cameras are installed, video motion sensors can be 
used to detect intruder movement within the area. Because ultrasonic motion sensors 
are seldom used, they will not be discussed herein.
_		 Microwave motion sensors. With microwave motion sensors, high-frequency 
electromagnetic energy is used to detect an intruders motion within the 
protected area. Interior or sophisticated microwave motion sensors are normally 
used.
   Interior microwave motion sensors. Interior microwave motion sensors are 
typically monostatic; the transmitter and the receiver are housed in the 
same enclosure (transceiver). 
    Sophisticated microwave motion sensors. Sophisticated microwave motion 
sensors may be equipped with electronic range gating. This feature allows 
the sensor to ignore the signals reflected beyond the settable detection 
range. Range gating may be used to effectively minimize unwanted alarms 
from activity outside the protected area.
_		 Passive infrared (PIR) motion sensors. PIR motion sensors detect a change in 
the thermal energy pattern caused by a moving intruder and initiate an alarm 
when the change in energy satisfies the detectors alarm criteria. These sensors 
are passive devices because they do not transmit energy; they monitor the energy 
radiated by the surrounding environment. 
_		 Dual technology sensors. To minimize the generation of alarms caused by 
sources other than intruders, dual-technology sensors combine two different 
technologies in one unit. Ideally, this is achieved by combining two sensors that 
individually have a high probability of detection (POD) and do not respond to 
common sources of false alarms. Available dual-technology sensors combine an 
active ultrasonic or microwave sensor with a PIR sensor. The alarms from each 
sensor are logically combined in an "and" configuration (i.e., nearly simultaneous 
alarms from both active and passive sensors are needed to produce a valid alarm). 
_		 Video motion sensors. A video motion sensor generates an alarm when an 
intruder enters a selected portion of a CCTV cameras field of view. The sensor 
processes and compares successive images between the images against predefined 
alarm criteria. There are two categories of video motion detectors, analog and 
digital. Analog detectors generate an alarm in response to changes in a pictures 
contrast. Digital devices convert selected portions of the analog video signal into 
digital data that are compared with data converted previously; if differences exceed 
preset limits, an alarm is generated. The signal processor usually provides an 
adjustable window that can be positioned anywhere on the video image. Available 
adjustments permit changing horizontal and vertical window size, window 
position, and window sensitivity. More sophisticated units provide several 
adjustable windows that can be individually sized and positioned. Multiple 
windows permit concentrating on several specific areas of an image while 
ignoring others. For example, in a scene containing six doorways leading into a 
long hallway, the sensor can be set to monitor only two critical doorways.
_		 Point sensors. Point sensors are used to protect specific objects within a 
facility. These sensors (sometimes referred to as proximity sensors) detect an 
intruder coming in close proximity to, touching, or lifting an object. Several 
different types are available, including capacitance sensors, pressure mats, and 
pressure switches. Other types of sensors can also be used for object protection.
_		Capacitance sensors. Capacitance sensors detect an intruder approaching or 
touching a metal object by sensing a change in capacitance between the object 
and the ground. A capacitor consists of two metallic plates separated by a 
dielectric medium. A change in the dielectric medium or electrical charge results 
in a change in capacitance. In practice, the metal object to be protected forms one 
plate of the capacitor and the ground plane surrounding the object forms the 
second plate. The sensor processor measures the capacitance between the metal 
object and the ground plane. An approaching intruder alters the dielectric value, 
thus changing the capacitance. If the net capacitance change satisfies the alarm 
criteria, an alarm is generated. 
_		Pressure mats. Pressure mats generate an alarm when pressure is applied to 
any part of the mats surface, such as when someone steps on the mat. One type of 
construction uses two layers of copper screening separated by soft-sponge rubber 
insulation with large holes in it. Another type uses parallel strips of ribbon 
switches made from two strips of metal separated by an insulating material and 
spaced several inches apart. When enough pressure is applied to the mat, either 
the screening or the metal strips make contact, generating an alarm. Pressure 
mats can be used to detect an intruder approaching a protected object, or they can 
be placed by doors or windows to detect entry. Because pressure mats are easy to 
bridge, they should be well concealed, such as placing them under a carpet.
_		 Pressure switches. Mechanically activated contact switches or single ribbon 
switches can be used as pressure switches. Objects that require protection can be 
placed on top of the switch. When the object is moved, the switch actuates and 
generates an alarm. In this usage, the switch must be well concealed. The interface 
between the switch and the protected object should be designed so that an 
adversary cannot slide a thin piece of material under the object to override the 
switch while the object is removed.

EXTERIOR INTRUSION DETECTION SENSORS
Exterior intrusion detection sensors are customarily used to detect an intruder 
crossing the boundary of a protected area. They can also be used in clear zones 
between fences or around buildings, for protecting materials and equipment stored 
outdoors within a protected boundary, or in estimating the POD for buildings and 
other facilities. 
Because of the nature of the outdoor environment, exterior sensors are also more 
susceptible to nuisance and environmental alarms than interior sensors. Inclement 
weather conditions (e.g., heavy rain, hail, and high wind), vegetation, the natural 
variation of the temperature of objects in the detection zone, blowing debris, and 
animals are major sources of unwanted alarms. 
Due to this vulnerability, it is extremely important that enclosures are located and 
installed properly and that adequate physical protection is provided. Several different 
types of exterior intrusion detection sensors are available:
_		Fence sensors
_		Buried line sensors
_		Video motion sensors    
FENCE SENSORS
Fence sensors detect attempts to penetrate a fence around a protected area. 
Penetration attempts (e.g., climbing, cutting, or lifting) generate mechanical 
vibrations and stresses in fence fabric and posts that are usually different than those 
caused by natural phenomena like wind and rain. The basic types of sensors used to 
detect these vibrations and stresses are strain sensitive cable, taut wire, fiber optics, 
and capacitance.
_		 Strain sensitive cables. Strain sensitive cables are transducers that are 
uniformly sensitive along their entire length. They generate an analog voltage 
when subject to mechanical distortions or stress resulting from fence motion. 
Strain sensitive cables are sensitive to both low and high frequencies. Because the 
cable acts like a microphone, some manufacturers offer an option that allows the 
operator to listen to fence noises causing the alarm. Operators can then 
determine whether the noises are naturally occurring sounds from wind or rain or 
are from an actual intrusion attempt. 
_		 Taut wire sensors. Taut wire sensors combine a physically taut-wire barrier 
with an intrusion detection sensor network. The taut wire sensor consists of a 
column of uniformly spaced horizontal wires up to several hundred feet in length 
and securely anchored at each end. Typically, the wires are spaced 4 to 8 inches 
apart. Each is individually tensioned and attached to a detector located in a sensor 
post. Two types of detectors are commonly used, mechanical switches and strain 
gauges.
_		 Fiber optic cable sensors. Fiber optic cable sensors are functionally equivalent 
to the strain-sensitive cable sensors previously discussed. However, rather than 
electrical signals, modulated light is transmitted down the cable and the resulting 
received signals are processed to determine whether an alarm should be initiated. 
Because the cable contains no metal and no electrical signal is present, fiber optic 
sensors are generally less susceptible to electrical interference from lightning or 
other sources.
_		 Capacitance proximity sensors. Capacitance proximity sensors measure the 
electrical capacitance between the ground and an array of sense wires. Any 
variations in capacitance, such as that caused by an intruder approaching or 
touching one of the sense wires, initiates an alarm. These sensors usually consist 
of two or three wires attached to outriggers along the top of an existing fence, 
wall, or roof edge. 
BURIED LINE SENSORS
A buried line sensor system consists of detection probes or cable buried in the 
ground, typically between two fences that form an isolation zone. These devices are 
wired to an electronic processing unit. The processing unit generates an alarm if an 
intruder passes through the detection field. Buried line sensors have several sig-
nificant features:
_		They are hidden, making them difficult to detect and circumvent.
_		They follow the terrains natural contour.
_		They do not physically interfere with human activity, such as grass mowing or 
snow removal.
_		They are affected by certain environmental conditions, such as running water 
and ground freeze/thaw cycles. (Seismic, seismic/magnetic, magnetic, and 
balanced pressure sensors are seldom used and will not be discussed herein.)
MICROWAVE SENSORS
Microwave intrusion detection sensors are categorized as bistatic or monostatic. 
Bistatic sensors use transmitting and receiving antennas located at opposite ends of 
the microwave link, whereas monostatic sensors use the same antenna.
_		A bistatic system uses a transmitter and a receiver that are typically separated 
by 100 to 1,200 feet and that are within direct LOS of each other. 
_		Monostatic microwave sensors use the same antenna or virtually coincident 
antenna arrays for the transmitter and receiver, which are usually combined into a 
single package. 
INFRARED (IR) SENSORS
The IR sensors are available in both active and passive models. An active sensor 
generates one or more near-IR beams that generate an alarm when interrupted. A 
passive sensor detects changes in thermal IR radiation from objects located within its 
field of view.
Active sensors consist of transmitter/receiver pairs. The transmitter contains an IR 
light source (such as a gallium arsenide light-emitting diode [LED]) that generates 
an IR beam. The light source is usually modulated to reduce the sensors 
susceptibility to unwanted alarms resulting from sunlight or other IR light sources. 
The receiver detects changes in the signal power of the received beam. To minimize 
nuisance alarms from birds or blowing debris, the alarm criteria usually require that 
a high percentage of the beam be blocked for a specific interval of time. 
VIDEO MOTION SENSORS
Video motion sensors are available on most digital video recorders used in security 
applications. They can be programmed to activate alarms, initiate recording, or any 
other designated action when motion is detected by a security camera. Some digital 
video recorders can be programmed to monitor very specific fields of view for specific 
rates of motion in order to increase effectiveness and minimize extraneous 
detections. Video motion sensors can also greatly improve the efficiency of security 
personnel monitoring security cameras by alerting them when motion is detected.
ELECTRONIC ENTRY CONTROL
The function of an entry control system is to ensure that only authorized personnel 
are permitted into or out of a controlled area. Entry can be controlled by locked fence 
gates, locked doors to a building or rooms within a building, or specially designed 
portals. 
These means of entry control can be applied manually by guards or automatically by 
using entry control devices. In a manual system, guards verify that a person is 
authorized to enter an area, usually by comparing the photograph and personal 
characteristics of the individual requesting entry. In an automated system, the entry 
control device verifies that a person is authorized to enter or exit. The automated 
system usually interfaces with locking mechanisms on doors or gates that open 
momentarily to permit passage. Mechanical hardware (e.g., locking mechanisms, 
electric door strikes, and specially designed portal hardware) and equipment used to 
detect contraband material (e.g., metal detectors, X-ray baggage-search systems, 
explosives detectors, and special nuclear-material monitors) are described in other 
documentation. 
All entry control systems control passage by using one or more of three basic 
techniques (e.g., something a person knows, something a person has, or something a 
person is or does). Automated entry control devices based on these techniques are 
grouped into three categories: coded, credential, and biometric devices.
CODED DEVICES
Coded devices operate on the principle that a person has been issued a code to enter 
into an entry control device. This code will match the code stored in the device and 
permit entry. Depending on the application, a single code can be used by all persons 
authorized to enter the controlled area or each authorized person can be assigned a 
unique code. Group codes are useful when the group is small and controls are 
primarily for keeping out the general public. Individual codes are usually required for 
control of entry to more critical areas. Coded devices verify the entered codes 
authenticity, and any person entering a correct code is authorized to enter the 
controlled area. Electronically coded devices include electronic and computer-
controlled keypads.
Electronic Keypad Devices. The common telephone keypad (12 keys) is an example of 
an electronic keypad. This type of keypad consists of simple push-button switches 
that, when depressed, are decoded by digital logic circuits. When the correct 
sequence of buttons is pushed, an electric signal unlocks the door for a few seconds.
Computer-controlled Keypad Devices. These devices are similar to electronic keypad 
devices, except they are equipped with a microprocessor in the keypad or in a separate 
enclosure at a different location. The microprocessor monitors the sequence in 
which the keys are depressed and may provide additional functions such as personal 
ID and digit scrambling. When the correct code is entered and all conditions are 
satisfied, an electric signal unlocks the door.
CREDENTIAL DEVICES
A credential device identifies a person having legitimate authority to enter a 
controlled area. A coded credential (e.g., plastic card or key) contains a prerecorded, 
machine-readable code. An electric signal unlocks the door if the prerecorded code 
matches the code stored in the system when the card is read. Like coded devices, 
credential devices only authenticate the credential; it assumes a user with an 
acceptable credential is authorized to enter. The most commonly used types of cards 
are described as follows:
Magnetic-stripe Card. A strip of magnetic material located along one edge of the card 
is encoded with data (sometimes encrypted). The data is read by moving the card past 
a magnetic read head. 
Wiegand-effect Card. The Wiegand-effect card contains a series of small-diameter, 
parallel wires approximately 12-inch long, embedded in the bottom half of the card. 
The wires are manufactured from ferromagnetic materials that produce a sharp 
change in magnetic flux when exposed to a slowly changing magnetic field. This type 
of card is impervious to accidental erasure. The card reader contains a small read 
head and a tiny magnet to supply the applied magnetic field. It usually does not 
require external power. 
Proximity Card. A proximity card is not physically inserted into a reader; the coded 
pattern on the card is sensed when it is brought within several inches of the reader. 
Several techniques are used to code cards. One technique uses a number of 
electrically tuned circuits embedded in the card. Data are encoded by varying 
resonant frequencies of the tuned circuits. The reader contains a transmitter that 
continually sweeps through a specified range of frequencies and a receiver that 
senses the pattern of resonant frequencies contained in the card. Another technique 
uses an integrated circuit embedded in the card to generate a code that can be 
magnetically or electro-statically coupled to the reader. The power required to activate 
embedded circuitry can be provided by a small battery embedded in the card or by 
magnetically coupling power from the reader.
Smart Card. A smart card is embedded with a microprocessor, memory, 
communication circuitry, and a battery. The card contains edge contacts that enable 
a reader to communicate with the microprocessor. Entry control information and 
other data may be stored in the microprocessors memory.
Bar Code. A bar code consists of black bars printed on white paper or tape that can be 
easily read with an optical scanner. This type of coding is not widely used for entry 
control applications because it can be easily duplicated. It is possible to conceal the 
code by applying an opaque mask over it. In this approach, an IR scanner is used to 
interpret the printed code. For low-level security areas, the use of bar codes can 
provide a cost-effective solution for entry control. Coded strips and opaque masks can 
be attached to existing ID badges, alleviating the need for complete badge re-
placement.
BIOMETRIC DEVICES
The third basic technique used to control entry is based on the measurement of one 
or more physical or personal characteristics of an individual. Because most entry 
control devices based on this technique rely on measurements of biological 
characteristics, they have become commonly known as biometric devices. 
Characteristics such as fingerprints, hand geometry, voiceprints, handwriting, and 
retinal blood-vessel patterns have been used for controlling entry. Typically, in 
enrolling individuals, several reference measurements are made of the selected 
characteristic and then stored in the devices memory or on a card. From then on, 
when that person attempts entry, a scan of the characteristic is compared with the 
reference data template. If a match is found, entry is granted. Rather than verifying an 
artifact, such as a code or a credential, biometric devices verify a persons physical 
characteristic, thus providing a form of identity verification. Because of this, 
biometric devices are sometimes referred to as personnel identity verification devices. 
The most common biometric devices are discussed below.
Fingerprints. Fingerprint-verification devices use one of two approaches. One is 
pattern recognition of the whorls, loops, and tilts of the referenced fingerprint, 
which is stored in a digitized representation of the image and compared with the 
fingerprint of the prospective entrant. The second approach is minutiae comparison, 
which means that the endings and branching points of ridges and valleys of the 
referenced fingerprint are compared with the fingerprint of the prospective entrant.
Hand Geometry. Several devices are available that use hand geometry for personnel 
verification. These devices use a variety of physical measurements of the hand, such as 
finger length, finger curvature, hand width, webbing between fingers, and light 
transmissivity through the skin to verify identity. Both two- and three-dimensional 
units are available.
Retinal Patterns. This type of technique is based on the premise that the pattern of 
blood vessels on the human eyes retina is unique to an individual. While the eye is 
focused on a visual target, a low-intensity IR light beam scans a circular area of the 
retina. The amount of light reflected from the eye is recorded as the beam progresses 
around the circular path. Reflected light is modulated by the difference in reflectivity 
between blood-vessel pattern and adjacent tissue. This information is processed and 
converted to a digital template that is stored as the eyes signature. Users are allowed 
to wear contact lenses; however, glasses should be removed.

MONITORING OF DESIGNATED RESTRICTED AREAS
A restricted area is any area that can be monitored by electronic devices and that is 
subject to special restrictions or controls for security reasons. Restricted areas may be 
established for the following:
_	 The enforcement of security measures and the exclusion of unauthorized 
personnel.
_	 Intensified controls in areas requiring special protection.
_	 The protection of classified information or critical equipment or materials.
DEGREE OF SECURITY
The degree of security and control required depends on the nature, sensitivity, or 
importance of the security interest. Restricted areas are classified as controlled, 
limited, or exclusion areas:
Controlled Area. A controlled area is that portion of a restricted area usually near or 
surrounding a limited or exclusion area. Entry to the controlled area is restricted to 
personnel with a need for access. Movement of authorized personnel within this area 
is not necessarily controlled because mere entry to the area does not provide access to 
the security interest. The controlled area is provided for administrative control, for 
safety, or as a buffer zone for indepth security for the limited or exclusion area. 
Limited Area . A limited area is a restricted area within close proximity of a security 
interest. Uncontrolled movement may permit access to the item. Escorts and other 
internal restrictions may prevent access within limited areas.
Exclusion Area. An exclusion area is a restricted area containing a security interest. 
Uncontrolled movement permits direct access to the item.
There are other important considerations concerning restricted areas and their lines 
of division. These considerations include the following: 
_	 A survey and analysis of the facility, its missions, and its security interests. This 
can determine immediate and anticipated needs that require protection. 
Anticipated needs are determined from plans for the future.
_	 The size and nature of the security interest being protected. Safes may provide 
adequate protection for classified documents and small items; however, large 
items may have to be placed within guarded enclosures.
_	 Some security interests are more sensitive to compromise than others. Brief 
observation or a simple act by an untrained person may constitute a compromise 
in some cases. In others, detailed study and planned action by an expert may be 
required




BIBLIOGRAPHY    



American Association of State Highway and Transportation Officials
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Mallonee, S. Shariat, G. Stennies, R. Waxweiler, D. Hogan, and F. Jordan., The Journal 
of the American Medical Association, Vol. 276 No. 5., pp 382-387  Abstract at URL: 
http://jama.ama-assn.org/cgi/content/abstract/276/5/382
American Society of Civil Engineers
Architectural Engineering Institute of American Society of Civil Engineers, AEI 
Newsletter, The Team, Special Terrorism Issue, Fall 2001, Volume 4, Issue 3     
http://www.asce.org/pdf/aei_11_1.pdf
Blast Effects on Buildings: Design of Buildings to Optimize Resistance to Blast Loading, 1995, G.C. 
Mays and P.D. Smith, London: Thomas Telford, Ltd., American Society of Civil 
Engineers, ISBN: 0-7277-2030-9http://www.pubs.asce.org/BOOKdisplay.cgi?9990338
Blast Resistant Design of Commercial Buildings, 1996, M. Ettouney, R. Smilowitz, and T. 
Rittenhouse, Practice Periodical on Structural Design and Construction, Vol. 1, No. 1, 
February 1996, American Society of Civil Engineers  
http://ojps.aip.org/dbt/dbt.jsp?KEY=PPSCFX&Volume=1&Issue=1A preprint of the 
final article is available at http://www.wai.com/AppliedScience/Blast/blast-struct-
design.html
Design of Blast Resistant Buildings in Petrochemical Facilities, 1997, American Society of Civil 
Engineers, ISBN: 0-7844-0265-5  http://www.pubs.asce.org/BOOKdisplay.cgi?9704510
Glass-Related Injuries in Oklahoma City Bombing, Journal of Performance of Constructed 
Facilities, May 1999, 13, No. 2, H Scott Norville, Natalie Harville, Edward J. Conrath, 
Sheryll Shariat, and Sue Mallonee   
http://www.pubs.asce.org/WWWdisplay.cgi?9902006
Lessons from the Oklahoma City Bombing: Defensive Design Techniques, January 1997, Eve E. 
Hinman and David J. Hammond, January 1997, American Society of Civil Engineers 
(ASCE Press), Reston, VA, ISBN: 0784402175  
http://www.asce.org/publications/booksdisplay.cfm?type=9702295
Minimum Design Loads for Buildings and Other Structures, ASCE 7-02, 2002, American Society 
of Civil Engineers, ISBN: 0-7844-0624-3 [Note revision of 7-98, does not include 
building security or antiterrorism, but covers all natural hazards]  
http://www.pubs.asce.org/ASCE7.html?9991330
Structural Engineering Institute of American Society of Civil Engineers, Structural 
Design for Physical Security: State of the Practice, 1999, Edward Conrath, et al., Reston, VA, 
Structural Engineering Institute of American Society of Civil Engineers  
http://www.pubs.asce.org/BOOKdisplay.cgi?9990571

Vulnerability and Protection of Infrastructure Systems: The State of the Art, An ASCE Journals 
Special Publication compiling articles from 2002 and earlier available online   
https://ascestore.aip.org/OA_HTML/aipCCtpItmDspRte.jsp?a=b& item=39885
American Society of Heating, Refrigerating, and Air-Conditioning Engineers
Defensive Filtration, ASHRAE Journal, December 2002, James D. Miller  
http://resourcecenter.ashrae.org/store/ashrae/newstore.cgi?itemid= 
9346&view=item&categoryid=409&page=1&loginid=29483
Report of Presidential Ad Hoc Committee for Building Health and Safety under Extraordinary 
Incidents on Risk Management Guidance for Health, Safety and Environmental Security under 
Extraordinary Incidents, Washington, DC, January 26, 2003  
http://xp20.ashrae.org/about/extraordinary.pdf
Risk Management Guidance for Health and Safety under Extraordinary Incidents, ASHRAE 2002 
Winter Meeting Report, January 12, 2002  
http://atfp.nfesc.navy.mil/pdf/ASHRAE%20CBR%20Guidance.pdfor 
http://engineering.tamu.edu/safety/guidelines/faclab/ASHRAE_ 
Security_Rpt_12Jan02.pdf
Standard 62-2001, Ventilation for Acceptable Indoor Air Quality (ANSI Approved), ISSN 1041-
2336, addenda to basic ANSI/ASHRAE Standard 62 basic (1989)  
http://resourcecenter.ashrae.org/store/ashrae/newstore.cgi? itemid= 
6852&view=item&categoryid=311&page=1&loginid=29483
Building Owners and Managers Association International
How to Design and Manage Your Preventive Maintenance Program, 1996  
http://www.boma.org/pubs/bomapmp.htm

Centers for Disease Control and Prevention/National Institute for Occupational Safety 
and Health
Publication No. 2002-139, Guidance for Protecting Building Environments from Airborne 
Chemical, Biological, or Radiological Attacks, May 2002, Cincinnati, OH  
http://www.cdc.gov/niosh/bldvent/2002-139.html
Publication No. 2003-136, Guidance for Filtration and Air Cleaning Systems to Protect Building 
Environments from Airborne Chemical, Biological, or Radiological Attacks, April 2003, 
Cincinnati, OHhttp://www.cdc.gov/niosh/docs/2003-136/2003-136.html
Central Intelligence Agency
Chemical, Biological, Radiological Incident Handbook, October 1998  
http://www.cia.gov/cia/publications/cbr_handbook/cbrbook.htm
Council on Tall Buildings and Urban Habitat
Building Safety Enhancement Guidebook, 2002http://www.ctbuh.org
Task Force on Tall Buildings: "The Future," October 15, 2001  
http://www.lehigh.edu/ctbuh/htmlfiles/hot_links/report.pdfor 
http://www.ctbuh.org/htmlfiles/hot_links/report.pdf
Federal Aviation Administration
DOT/FAA/AR-00/52, Recommended Security Guidelines for Airport Planning, Design and 
Construction, Revised June 2001, Associate Administrator for Civil Aviation Security 
Office of Civil Aviation Security, Policy and Planning, Federal Aviation 
Administration, Washington, DC 20591  (not available on Internet)
FAA Order 1600.69A, FAA Facility Security Management Program, updated FAA Order 
1600.69B to be published shortly  The Federal Aviation Administrations criteria for 
the protection of its facilities. [For Official Use Only]  (not available on Internet)

Federal Emergency Management Agency
FEMA 152, Seismic Considerations: Apartment Buildings, Earthquake Hazards Reduction Series 
37, November 1988, Washington, DC (not available on Internet)  Contact FEMA 
Distribution Center, P.O. Box 2012, 8231 Stayton Drive, Jessup, MD 20794-2012, 
Telephone: 1-800-480- 2520, Fax: 301-362-5335
FEMA 153, Seismic Considerations: Office Buildings, Earthquake Hazards Reduction Series 38, 
November 1988, Washington, DC (not available on Internet)  Contact FEMA 
Distribution Center, P.O. Box 2012, 8231 Stayton Drive, Jessup, MD 20794-2012, 
Telephone: 1-800-480-2520, Fax: 301-362-5335
FEMA 154, Rapid Visual Screening of Buildings for Seismic Hazards: A Handbook (2nd Edition), 
2002, 1988, Washington, DC (not available on Internet)  Contact FEMA Distribution 
Center, P.O. Box 2012, 8231 Stayton Drive, Jessup, MD 20794-2012, Telephone: 1-800-
480-2520, Fax: 301-362-5335
FEMA 277, The Oklahoma City Bombing: Improving Building Performance through Multi-Hazard 
Mitigation, August 1, 1996, Washington, DC 
http://www.fema.gov/mit/bpat/bpat009.htm
FEMA 372, Mitigation Resources for Success (CD-ROM), October 2001, Washington, DC 
http://www.fema.gov/pdf/library/poster_fnl2.pdf
FEMA 386-2, Understanding Your Risks, Identifying Hazards and Estimating Losses, August 
2001http://www.fema.gov/fima/planning_toc3.shtm
FEMA 386-7, Integrating Human-Caused Hazards Into Mitigation Planning, September 
2002http://www.fema.gov/fima/antiterrorism/resources.shtm
FEMA 403, World Trade Center Building Performance Study: Data Collection, Preliminary 
Observations, and Recommendations, May 2002, Washington, DC 
http://www.fema.gov/library/wtcstudy.shtm
State and Local Guide 101, Guide for All-Hazard Emergency Operations Planning, Chapter 6, 
Attachment G, Terrorism, April 2001http://www.fema.gov/rrr/allhzpln.shtm
General Services Administration
Balancing Security and Openness: A Thematic Summary of a Symposium on Security and the 
Design of Public Buildings, November 30, 1999  
http://hydra.gsa.gov/pbs/pc/gd_files/SecurityOpenness.pdf
 Cost Impact of ISC Security Criteria, GSA & Applied Research Associates, Inc., L. Bryant  
and J. Smith, Vicksburg, MS  [Restricted Access]  
http://www.oca.gsa.gov/specialphp/References.php
Facility Standards for the Public Building Service (PBS-P100); Chapter 8, Security Design, 
Revised November 2000http://hydra.gsa.gov/pbs/pc/facilitiesstandards/
Mail Center Managers Security Guide  Second Edition, October 22, 2002  
http://www.gsa.gov//attachments/GSA_PUBLICATIONS/extpub/MailCenterManag
ersSecurityGuideV2.pdf
Progressive Collapse Analysis and Design Guidelines for New Federal Office 
Buildings and Major Modernization Projects, November 2000  [Restricted Access]  
http://www.oca.gsa.gov/specialphp/References.php
Security Reference Manual, Part 3: Blast Design and Assessment Guidelines, July 31, 2001  
[For Official Use Only]  [Restricted Access]  
http://www.oca.gsa.gov/specialphp/References.php
Healthly Building International, Inc.
Vulnerability Assessments and Counter Terrorist Protocols  
http://www.healthybuildings.com/s2/vacbt.pdf
Interagency Security Committee (executive agent  GSA)
ISC Security Design Criteria for New Federal Office Buildings and Major Modernization Projects, 
May 28, 2001, [For Official Use Only] [Restricted Access]  
http://www.oca.gsa.gov/specialphp/References.php
Institute of Transportation Engineers
The Influence of Traffic Calming Devices upon Fire Vehicle Travel Times, Michael A. Coleman, 
1997, ITE Annual Meeting Compendium, 1997 pp. 838-845  
http://webservices.camsys.com/fhwa/cmn/cmn33.htm
Split Speed Bump, 1998, Kathy Mulder, Washington, DC, TE International Conference, 
1998http://www.ite.org/traffic/documents/CCA98A33.pdf
Lawrence Berkeley National Lab
Protecting Buildings From a Biological or Chemical Attack: actions to take before or during a release. 
LBNL/PUB-51959, January 10, 
2003http://securebuildings.lbl.gov/images/bldgadvice.pdf
National Academy of Sciences
Combating Terrorism: Prioritizing Vulnerabilities and Developing Mitigation Strategies, Project 
Identification Number: NAEP-R-02-01-A, National Academy of Engineering on-going 
project  results to be published. 
http://www4.nationalacademies.org/webcr.nsf/ProjectScopeDisplay/ NAEP-R-02-01-
A?OpenDocument
National Capital Planning Commission
Designing for Security in the Nations Capital, October 2001 
http://www.ncpc.gov/planning_init/security/DesigningSec.pdf 
The National Capital Planning Urban Design and Security Plan, October 
2002http://www.ncpc.gov/publications/udsp/Final%20UDSP.pdf

National Institute of Building Sciences
Whole Building Design Guide: Provide Security for Building Occupants and Assets 
http://www.wbdg.org/design/index.php?cn=2.7.4&cx=0
National Research Council
Protecting Buildings and People from Terrorism: Technology Transfer for Blast-effects Mitigation, 
2001, National Academy Press, Washington, DC, ISBN 0-309-08286-2  
http://books.nap.edu/books/0309082862/html/index.html
Protecting Buildings From Bomb Blast, Transfer of Blast-Effects Mitigation Technologies from 
Military to Civilian Applications, 1995, National Academy Press, Washington, DC, ISBN  0-
309-05375-7http://books.nap.edu/books/0309053757/html/index.html
Protection of Federal Office Buildings Against Terrorism, 1988, Committee on the Protection of 
Federal Facilities Against Terrorism, Building Research Board, National Academy Press, 
Washington, DC,  ISBN 0-309-07691-9  
http://books.nap.edu/books/0309076463/html/index.html
Society of American Military Engineers
National Symposium of Comprehensive Force Protection, October 2001, Charleston, 
SC, Lindbergh & Associates. For a list of participants, access 
http://www.same.org/forceprot/force.htm
Technical Support Working Group (TSWG)
Terrorist Bomb Threat Stand-Off Card with Explanation of Use 
http://www.tswg.gov/tswg/prods_pubs/newBTSCPress.htm
The House National Security Committee
Statement of Chairman Floyd D. Spence on the Report of the Bombing of Khobar 
Towers, August 1996, Washington, DC 
http://www.house.gov/hasc/Publications/104thCongress/Reports/saudi.pdf
U.S. Air Force
ESL-TR-87-57, Protective Construction Design Manual, November 1989; Contact Airbase 
Technologies Division (AFRL/MLQ) at Tyndall Air Force Base, FL, via e-mail to 
techinfo@afrl.af.mil. [Superceded by Army Technical Manual TM 5-855-1 (Air Force 
Pamphlet AFPAM 32-1147(I), Navy Manual NAVFAC P-1080, DSWA Manual 
DAHSCWEMAN-97), December 1997]
Expedient Hardening Methods for Structures Subjected to the Effect of Nonnuclear Munitions, 
October 1990, Wright Laboratory Report (not available on Internet)
Installation Entry Control Facilities Design Guide, October 2002, Air Force Center for 
Environmental Excellencehttp://www.afcee.brooks.af.mil/dc/dcd/gate/index.html
Installation Force Protection Guide, 1997, Air Force Center for Environmental Excellence  
http://www.afcee.brooks.af.mil/dc/dcd/arch/force.pdf
Vehicle Bomb Mitigation Guide, July 1, 1999, Force Protection Battlelab [For Official Use 
Only] Contact the USAF Force Protection Battlelab, Lackland Air Force Base, TX, 
Telephone: (210)671-0058
U.S. Army
Field Manuals (FM)
FM 3-19.30, Physical Security, January 8, 2001, Washington, DC 
http://www.adtdl.army.mil/cgi-bin/atdl.dll/fm/3-19.30/fm3-19.30.pdfor 
http://www.wood.army.mil/mpdoctrine/PDF_Files/FM_3-19.30.pdf
FM 5-114, Engineer Operations Short of War, July 13, 1992http://155.217.58.58/cgi-
bin/atdl.dll/fm/5-114/toc.htm
Technical Instruction 853-01 (Draft), Protecting Buildings and Their Occupants from 
Airborne Hazards, October 2001  
http://buildingprotection.sbccom.army.mil/basic/airborne_hazards

U.S. Army Corps of Engineers
Engineer Technical Letters (ETL)
ETL 1110-3-494, Airblast Protection Retrofit for Unreinforced Concrete Masonry Walls, 
July 14, 1999 [Restricted Access]  http://www.usace.army.mil/inet/usace-
docs/eng-tech-ltrs
ETL 1110-3-495, Estimating Damage to Structures from Terrorist Bombs Field Operations 
Guide, July 14, 1999 [Restricted Access]  http://www.usace.army.mil/inet/usace-
docs/eng-tech-ltrs
ETL 1110-3-498, Design of Collective Protection Shelters to Resist Chemical, Biological, and 
Radiological (CBR) Agents, February 24, 1999  
http://www.usace.army.mil/inet/usace-docs/eng-tech-ltrs
ETL 1110-3-501, Window Retrofit Using Fragment Retention Film with Catcher Bar System, 
July 14, 1999 [Restricted Access]  http://www.usace.army.mil/inet/usace-
docs/eng-tech-ltrs
Protective Design  Mandatory Center of Expertise  Technical Reports
PDC-TR-91-6, Blast Analysis Manual, Part 1  Level of Protection Assessment Guide, July 
1991 [For Official Use Only] Contact U.S. Army Corps of Engineers Protective 
Design Center, ATTN: CENWO-ED-ST, 215 N. 17th Street, Omaha, NE 68102-
4978, Telephone: (402)221-4918
Technical Manuals (TM)
TM 5-853-1, Security Engineering Project Development, May 12, 1994, also Air Force 
Manual 32-1071, Volume 1 [For Official Use Only]  
http://www.usace.army.mil/inet/usace-docs/armytm
TM 5-853-2, Security Engineering Concept Design, May 12, 1994, also Air Force 
Manual 32-1071, Volume 2 [For Official Use Only]  
http://www.usace.army.mil/inet/usace-docs/armytm
TM 5-853-3, Security Engineering Final Design, May 12, 1994, also Air Force Manual 
32-1071, Volume 3 [For Official Use 
Only]http://www.usace.army.mil/inet/usace-docs/armytm
TM 5-853-4, Security Engineering Electronic Security Systems, May 12, 1994  
http://www.usace.army.mil/inet/usace-docs/armytm
TM 5-855-4, Heating, Ventilation, and Air Conditioning of Hardened 
Installations, November 28, 1986  http://www.usace.army.mil/inet/usace-
docs/armytm/tm5-855-4/toc.htm
TM 5-1300, Structures to Resist Accidental Explosions, November 19, 1990, (also Navy 
NAVFAC (Naval Facilities) P-397, Air Force Regulation 88-2);  Contact David 
Hyde, U.S. Army Engineer Research and Development Center, 3909 Halls Ferry 
Road, Vicksburg, MS 39180 or via e-mail to hyded@ex1.wes.army.mil
U.S. Department of Commerce
Administrative Orders (DAO)
DAO 206-5, Occasional Use of Public Areas in Public Buildings, December 9, 1986  
http://www.osec.doc.gov/bmi/daos/206-5.htm
DAO 207-1, Security Programs, June 24, 1991, Amended September 6, 1991  
http://www.osec.doc.gov/bmi/daos/207-1.htm
Critical Infrastructure Assurance Office
Vulnerability Assessment Framework 1.1, October 1998  
http://www.ciao.gov/resource/vulassessframework.pdf
Practices For Securing Critical Information Assets, January 2000  
http://www.ciao.gov/resource/Practices_For_Securing_ 
Critical_Information_Assets.pdf
U.S. Department of Defense
DoD Security Engineering Manual [Expected to have a major portion for public 
distribution once published as Unified Facilities Criteria and a smaller portion For 
Official Use Only similar to the UFC for AT Standards for Buildings listed below. 
This publication will replace Army Technical Manual 5-853 (Air Force Joint Manual 
32-1071), Volumes 1, 2, and 3 and Navy Military Handbook 1013/1A]
DoD O-2000.12-H, Protection of DoD Personnel and Activities Against Acts of Terrorism and 
Political Turbulence: Mandatory Standards and Implementing Guidance, with Changes 1 and 2, 
February 1993, Change 1  May 21, 1993, Change 2  October 3, 1997  [For Official Use 
Only]  http://www.dtic.mil/whs/directives/corres/pub1.html
Force Protection Equipment Demonstration IV, 6-8 May 2003http://www.fped4.org
Interim Antiterrorism/Force Protection Construction Standards, December 16, 1999  [For Official 
Use Only] Contact U.S. Army Engineer District, Omaha, NE ATTN: CENWO-ED-ST, 
215 North 17th Street, Omaha, NE 68102-4978, Telephone: (402)221-4918.
Interim Antiterrorism/Force Protection Construction Standards Progressive Collapse Guidance, 
April 4, 2000 (not available on Internet) Contact U.S. Army Corps of Engineers 
Protective Design Center, ATTN: CENWO-ED-ST, 215 N. 17th Street, Omaha, NE 
68102-4978, Telephone: (402)221-4918
Unified Facilities Criteria (UFC)
UFC 3-340-01, Design and Analysis of Hardened Structures to Conventional Weapons 
Effects, June 30, 2002 [For Official Use Only] [Formerly Army TM 5-855-
1]http://www.hnd.usace.army.mil/techinfo/ufc/UFC3-340-01 WEB.PDF
UFC 4-010-01, DoD Minimum Antiterrorism Standards for Buildings, July 31, 2002  
http://www.wbdg.org/ccbref/ccbdoc.php?category=ufc& docid=106&ref=1
Unified Facilities Guide Specifications (UFGS)
UFGS-02821A, Fencing, February 2002http://www.ccb.org/ufgs/pdf/02821A.pdf
UFGS-02840A, Active Vehicle Barriers, February 2002  
http://www.ccb.org/ufgs/pdf/02840A.pdf
UFGS-02841N, Traffic Barriers, August 2001   
http://www.ccb.org/ufgs/pdf/02841N.pdf
UFGS-08390A, Blast Resistant Doors, April 2001  
http://www.ccb.org/ufgs/pdf/08390.pdf
UFGS-08581, Blast Resistant Tempered Glass Windows, August 2001  
http://www.ccb.org/ufgs/pdf/08581.pdf
UFGS-08840A, Plastic Glazing, July 
1995https://www.ccb.org/ufgs/pdf/08840A.pdf
UFGS-08850, Fragment Retention Film for Glass, July 1992  
https://www.ccb.org/ufgs/pdf/08850.pdf
UFGS-11020, Security Vault Door, August 2002  
http://www.ccb.org/ufgs/pdf/11020.pdf
UFGS-11025, Forced Entry Resistant Components, August 2001  
http://www.ccb.org/ufgs/pdf/11025.pdf
UFGS-11035, Bullet-Resistant Components, April 2000  
http://www.ccb.org/ufgs/pdf/11035.pdf
UFGS-13095A, Electromagnetic (EM) Shielding, July 2001  
http://www.ccb.org/ufgs/pdf/13095A.pdf
UFGS-13420A, Self-Acting Blast Valves, November 1997  
http://www.ccb.org/ufgs/pdf/13420A.pdf
U.S. Department of Energy
DOE/TIC 11268, A Manual for the Prediction of Blast and Fragment Loadings on Structures, 
February 1992, Albuquerque. NM, Southwest Research Institute [not available on 
Internet]
U.S. Department of Homeland Security
National Strategy for Homeland Security, July 
2002http://www.dhs.gov/interweb/assetlibrary/nat_strat_hls.pdf
The National Strategy for the Physical Protection of Critical Infrastructures and Key Assets, 
February 2003http://www.dhs.gov/interweb/assetlibrary/Physical_Strategy.pdf
National Strategy to Secure Cyberspace, February 
2003http://www.dhs.gov/interweb/assetlibrary/National_Cyberspace_ Strategy.pdf
President's Homeland Security Advisory Council - Statewide Template Initiative, March 
2003http://www.dhs.gov/interweb/assetlibrary/Statewide_Template_Initiative.pdf
State and Local Actions for Homeland Security, July 
2002http://www.whitehouse.gov/homeland/stateandlocal/State_and_Local_Actions
_for_Homeland_Security.pdf
U.S. Department of Housing and Urban Development
The Avoidance of Progressive Collapse, Regulatory approaches to the problem, PB-248 781, October 
1975, Division of Energy, Building Technology and Standards, Office of Policy 
Development and Research, Washington, DC 20410  (not available on Internet)
Creating Defensible Space, April 1996, Oscar Newman, Washington, DC 
http://www.huduser.org 
U.S. Department of Justice
Federal Bureau of Investigation (FBI)
Terrorism in the United States, 1999, Washington, DC, Counterterrorism Division 
http://www.fbi.gov/publications.htm 
Office of Domestic Preparedness (ODP)
Fiscal Year 1999 State Domestic Preparedness Equipment Program, Assessment and Strategy 
Development Tool Kit, NCJ181200, May 15, 2000, [For Official Use Only]  
http://www.ojp.usdoj.gov/odp/docs/assessment.txt
National Institute of Justice (NIJ)
The Appropriate and Effective Use of Security Technologies in U.S. Schools: A Guide for 
Schools and Law Enforcement Agencies, September 1999, with U.S. Department of 
Education, Safe and Drug-Free Schools Program; and U.S. Department of 
Energy, Sandia National 
Laboratorieshttp://www.ncjrs.org/school/home.html
NIJ Guide 100-00, Guide for the Selection of Chemical Agent and Toxic Industrial 
Material Detection Equipment for Emergency First Responders, June 
2000http://www.ncjrs.org/pdffiles1/nij/184449.pdf
NIJ Guide 101-00, An Introduction to Biological Agent Detection Equipment for Emergency 
First Responders, December 2001http://www.ncjrs.org/pdffiles1/nij/190747.pdf
NIJ Guide 102-00, Guide for the Selection of Personal Protective Equipment for Emergency 
First Responders, Volumes I-IV, November 
2002http://www.ncjrs.org/pdffiles1/nij/191518.pdf
NIJ Guide 602-00, Guide to the Technologies of Concealed Weapon and Contraband 
Imaging and Detection, February 2001  
http://www.ncjrs.org/pdffiles1/nij/184432.pdf
NIJ Standard 0108.01, Blast Resistant Protective Materials, September 1985  
[Subscription Required]http://www.ccb.org
Crime Prevention Through Environmental Design and Community Policing, August 1996, 
Dan Fleissner and Fred Heinzelmann, Washington, DC 
http://www.ncjrs.org/pdffiles/crimepre.pdf
Crime Prevention Through Environmental Design in Parking Facilities, April 1996, Mary 
S. Smith, Washington, DChttp://www.ncjrs.org/pdffiles/cptedpkg.pdf
"Designing Out" Gang Homicides and Street Assaults, November 1998, James Lasley, 
Washington, DChttp://www.ncjrs.org/pdffiles/173398.pdf
The Expanding Role of Crime Prevention Through Environmental Design in Premises 
Liability, April 1996, Corey L. Gordon and William Brill Washington, DC 
http://www.ncjrs.org/pdffiles/cptedlia.pdf
Physical Environment and Crime, January 1996, Ralph B. Taylor and Adele V. 
Harrell, Washington, DChttp://www.ncjrs.org/pdffiles/physenv.pdf
Visibility and Vigilance: Metros Situational Approach to Preventing Subway Crime, 
November 1997, Nancy G La Vigne, Washington, DC 
http://www.ncjrs.org/pdffiles/166372.pdf
U.S. Marshals Service
Vulnerability Assessment of Federal Facilities, June 28, 1995  [Restricted 
Access]http://www.oca.gsa.gov
U.S. Department of State, Bureau of Diplomatic Security
Architectural Engineering Design Guidelines (5 Volumes), March 1998 [For Official Use Only] 
(not available on Internet)
Certification Standard SD-STD-01.01, Revision G (Amended), Forced Entry and Ballistic 
Resistance of Structural Systems, Amended April 30, 1993  [Subscription Required] 
http://www.ccb.org
Patterns of Global Terrorism, 2002, April 2002, Washington, DC 
http://www.state.gov/s/ct/rls/pgtrpt/2002/pdf/
Physical Security Standards Handbook, January 7, 1998 [For Official Use Only] (not available 
on Internet)
Structural Engineering Guidelines for New Embassy Office Buildings, August 1995 [For Official 
Use Only] (not available on Internet)
The Report of the Accountability Review Board on the Embassy Bombings in Nairobi and Dar es 
Salaam on August 7, 1998, January 1999, Washington, DC 
http://www.state.gov/www/regions/africa/accountability_report.html
U.S. Department of the Treasury/Bureau of Alcohol, Tobacco, and Firearms
Vehicle Bomb Explosion Hazard And Evacuation Distance Tables, 1999, request in writing, 
address information available at  http://www.atf.treas.gov/pub/fire-
explo_pub/i54001.htm
U.S. Department of Veterans Affairs
Physical Security Assessment of Veterans Affairs Facilities, Recommendations of the National 
Institute of Building Sciences Task Group to the Department of Veterans Affairs,  6 
September 2002  
http://www.va.gov/facmgt/standard/etc/vaphysicalsecurityreport.pdf
U.S. Fire Administration (USFA of FEMA)
The Critical Infrastructure Protection Process Job Aid, May 1, 2002  
http://www.usfa.fema.gov/dhtml/fire-service/cipc-jobaid.cfm
U.S. Navy
Design Manuals (DM) NAVFAC (Naval Facilities Command)
NAVFAC  DM 2.08, Blast Resistant Structures, December 1986  
http://www.wbdg.org/ccbref/ccbdoc.php?category=nav& docid=46&ref=1
NAVFAC DM 13.02, Commercial Intrusion Detection Systems (IDS), September 1986  
http://www.wbdg.org/ccbref/ccbdoc.php?category=nav& docid=47&ref=1
Interim Technical Guidance (ITG) 03-03, Entry Control Facilities, 20 February 
2003http://www.lantdiv.navfac.navy.mil/servlet page?pageid= 8609,8611 
&_dad= lantdiv&_schema=LANTDIV&11435_ACTIVE_1777132.p_ subid= 
60007&11435_ACTIVE_1777 132.p_sub_siteid=51 &11435_ 
ACTIVE_1777132.p_edit=0
Military Handbooks (MIL-HDBK)
MIL-HDBK-1002/1, Structural Engineering General Requirements, November 30, 1987  
http://www.wbdg.org/ccbref/ccbdoc.php?category=nav& docid=48&ref=1
MIL-HDBK-1004/4, Electrical Utilization Systems, October 13, 1987  
http://www.wbdg.org/ccbref/ccbdoc.php?category=nav& docid=49&ref=1
MIL-HDBK-1012/3, Telecommunications Premises Distribution Planning, Design, and 
Estimating, May 31, 1996  
http://www.wbdg.org/ccbref/ccbdoc.php?category=nav& docid=50&ref=1
MIL-HDBK-1013/1A, Design Guidelines for Physical Security of Fixed Land-Based 
Facilities, December 15, 1993. For copies, contact Defense Printing Service, 
Building 40, 700 Robbins Avenue, Philadelphia, PA 19111-5094, Telephone: 
(215)697-2179, Fax: (215)697-1462 or available on the National Institute of 
Building Sciences Construction Criteria Base
MIL-HDBK-1013/10, Design Guidelines for Security Fencing, Gates, Barriers, and Guard 
Facilities, May 14, 1993. For copies, contact Defense Printing Service, Building 
40, 700 Robbins Avenue, Philadelphia, PA 19111-5094, Telephone: (215)697-
2179, Fax: (215) 697-1462 or available on the National Institute of Building 
Sciences Construction Criteria Base
MIL-HDBK-1013/12, Evaluation of Security Glazing for Ballistic, Bomb, and Forced 
Entry Tactics, March 10, 1997. For copies, contact Defense Printing Service, 
Building 40, 700 Robbins Avenue, Philadelphia, PA 19111-5094, Telephone: 
(215)697-2179, Fax: (215) 697-1462 or available on the National Institute of 
Building Sciences Construction Criteria Base
MIL-HDBK-1013/14, Selection and Application of Vehicle Barriers, February 1, 1999. 
For copies, contact Defense Printing Service, Building 40, 700 Robbins Avenue, 
Philadelphia, PA 19111-5094, Telephone: (215)697-2179, Fax: (215)697-1462 or 
available on the National Institute of Building Sciences Construction Criteria 
Base
TechData Sheets  Naval Facilities Engineering Service Center (NFESC)
TDS-2062-SHR, Estimating Damage to Structures from Terrorist Bombs, September 1998  
[For Official Use Only] Requests for publication can be made to Naval Facilities 
Engineering Service Center, Security Engineering Division (ESC66), 1100 23rd 
Ave, Port Hueneme, CA 93043-4370, Telephone (805)982-1582 (Primary), 
(805)982-4817 (Alternate); Fax: (805)982-1253
TDS-2063-SHR, Blast Shielding Walls, September 1998 [For Official Use Only] 
Requests for publication can be made to Naval Facilities Engineering Service 
Center, Security Engineering Division (ESC66), 1100 23rd Ave., Port Hueneme, 
CA 93043-4370, Telephone: (805)982-1582 (Primary), (805)982-4817 (Alternate); 
Fax: (805)982-1253 
TDS-2079-SHR, Planning and Design Considerations for Incorporating Blast Mitigation in 
Mailrooms, May 2000. For copies, contact Defense Printing Service, Building 40, 
700 Robbins Avenue, Philadelphia, PA 19111-5094, Telephone: (215)697-2179, 
Fax: (215) 697-1462
TDS-2090-SHR, Design Parametesr for a Controlled Entry Point. For copies, contact 
Defense Printing Service, Building 40, 700 Robbins Avenue, Philadelphia, PA 
19111-5094, Telephone: (215)697-2179, Fax: (215)697-1462
User Guides  Naval Facilities Engineering Service Center (NFESC)
UG-2030-SHR, Security Glazing Applications, May 1998, distributed June 25, 1998. 
[For Official Use Only]  Requests for publication can be made to Naval Facilities 
Engineering Service Center, Security Engineering Division (ESC66), 1100 23rd 
Ave., Port Hueneme, CA 93043-4370, Telephone: (805)982-1582 (Primary), (805) 
982-4817 (Alternate); Fax: (805)982-1253
UG-2031-SHR, Protection Against Terrorist Vehicle Bombs, May 1998, distributed June 
25, 1998. [For Official Use Only]  Requests for publication can be made to Naval 
Facilities Engineering Service Center, Security Engineering Division (ESC66), 
1100 23rd Ave, Port Hueneme, CA 93043-4370, Telephone: (805)982-15.82 
(Primary), (805) 982-4817 (Alternate); Fax: (805)982-1253
Other Books, Magazines, Magazine Articles, and Newspaper Articles
Archibald, Rae W., et al., 2002, Security and Safety in Los Angeles High-Rise Buildings after 
9/11. RAND, Santa Monica, CA, ISBN: 0-8330-3184-8  
http://www.rand.org/publications/DB/DB381
Atlas, Randall I., June 1998, Designing for Crime and Terrorism, Security and Technology 
Design, Security Technology and Design Magazine Reprint Services, Jim Benesh, 
Telephone: (800)547-7377 x324, Fax: (920)568-2244, e-mail: 
jim.benesh@cygnuspub.com
Broder, James F., December 15, 1999, Risk Analysis and the Security Survey, 2nd Edition,  
Butterworth-Heinemann, Stoneham, MA, ISBN: 0750670894
Craighead, Geoff, December 2002, High-Rise Security and Fire Life Safety, 2nd Edition, 
Academic Press, ISBN: 0750674555
Crowe, Timothy D., 2000, Crime Prevention Through Environmental Design: Applications Of 
Architectural Design And Space Management Concepts (2nd Edition), Stoneham, MA, 
Butterworth-Heinemann, ISBN: 075067198X
Fehr, Stephen C., July 1996, Parking Under Siege in D.C.: U.S. Anti-Terrorism Plan 
Threatens 360 Spaces, The Washington Post, July 13, 
1996http://www.washingtonpost.com/wp-adv/archives/advanced.htm
Fenelly, Lawrence J, June 1997, Effective Physical Security, 2nd Edition, Stoneham, MA, 
Butterworth-Heinemann, ISBN: 0-75-069873-X 
Garcia, Mary Lynn, February 23, 2001, The Design and Evaluation of Physical Protection 
Systems, Stoneham, MA, Butterworth-Heinemann, ISBN: 0750673672 
Gonchar, Joann, March 2002, Building for a Secure Future: Government Facilities 
under way incorporate already tough standards, Engineering News-Record, March 25, 2002  
http://www.construction.com/NewsCenter/Headlines/ENR/20020325e.asp
Greene, R.W., October 2002, Confronting Catastrophe: A GIS Handbook, ESRI Press, ISBN: 
1589480406 
Hart, Sara, March 2002, In the aftermath of September 11, the urban landscape 
appears vulnerable and random: Architects and consultants focus on risk assessment 
and security through design, Architectural Record, March 2002  
http://archrecord.construction.com/CONTEDUC/ARTICLES/03_02_1.asp
Kowalski, Wladyslaw Jan, P.E., Ph.D., September 26, 2002, Immune Building Systems 
Technology, McGraw-Hill Professional, ISBN: 0-07-140246-2
Nadel, Barbara A, March 1998, Designing for Security, Architectural Record, March 1998  
http://www.archrecord.com/CONTEDUC/ARTICLES/3_98_1.asp
Owen, David D. and R.S.Means Engineering Staff, Building Security: Strategies and Costs, 
Construction Publishers & Consultants, ISBN: 0-87629-698-3, 2003
Pearson, Robert, September 1997, Security through Environmental Design, Security and 
Technology Design, Security Technology and Design Magazine Reprint Services, Jim 
Benesh, Telephone: (800) 547-7377 x324;  Fax: (920) 568-2244;  e-mail: 
jim.benesh@cygnuspub.com
Rochon, Donald M., June 1998, Architectural Design for Security, Security and Technology 
Design,  Security Technology and Design Magazine Reprint Services, Jim Benesh, 
Telephone: (800)547-7377 x324; Fax: (920)568-2244; e-mail: 
jim.benesh@cygnuspub.com
Security Magazine [on-line magazine]http://www.securitymagazine.com
Security Solutions Online: Access Control and Security Systems [on-line magazine] 
http://securitysolutions.com/
Security Technology and Design [on-line and print magazine]  http://www.st-and-
d.com
Sidell, Frederick R., et al, 1998, Janes Chem-Bio Handbook, Janes Information Group, 
Alexandria, VA, ISBN 0-7106 2568-5  
http://www.janes.com/company/catalog/chem_bio_hand.shtml
Smith, Keith, November 2000, Environmental Hazards: Assessing Risk and Reducing Disaster, 
Routledge, New York, NY, ISBN 0415224632  http://www.routledge-
ny.com/books.cfm?isbn=041522463




ASSOCIATIONS AND ORGANIZATIONS     



_		 American Lifelines Alliance  http://www.americanlifelinesalliance.org
_		 Applied Technology Council     http://www.atcouncil.org
_		 Battelle Memorial Institute, National Security Program   
http://www.battelle.org/natsecurity/default.stm
_		 Center for Strategic and International Studies (CSIS)  http://www.csis.org
_		 Centers for Disease Control and Prevention (CDC)/National Institute for 
Occupational Safety and Health (NIOSH)  http://www.cdc.gov/niosh
_		 Central Intelligence Agency (CIA)      http://www.cia.gov
_		 Council on Tall Buildings and Urban Habitat (CTBUH)  
http://www.ctbuh.org
_		 Federal Aviation Administration (FAA)  http://www.faa.gov
_		 Healthy Buildings International, Inc.  http://www.healthybuildings.com
_		 Institute of Transportation Engineers  http://www.ite.org
_		 Interagency Security Committee (ISC) led by the U.S. General Services 
Administration [Restricted Access]http://www.oca.gsa.gov
 _		International CPTED [Crime Prevention Through Environmental Design] 
Association (ICA)  http://new.cpted.net/home.amt
_		 Lawrence Berkeley National Laboratory (LBNL)  
http://securebuildings.lbl.gov
_		 National Academy of Sciences  
http://www4.nationalacademies.org/nas/nashome.nsf
 Federal Facilities Council (FFC) Standing Committee on Physical Security and 
Hazard Mitigation  
http://www7.nationalacademies.org/ffc/Physical_Security_ 
Hazard_Mitigation.html
 National Research Council  http://www.nationalacademies.org/nrc
_		 National Defense Industrial Association (NDIA)  http://www.ndia.org
_		 Public Entity Risk Institute http://www.riskinstitute.org
_		 Security Design Coalition  http://www.designingforsecurity.org
_		 Security Industry Association (SIA)  http://www.siaonline.org/
_		 Technical Support Working Group (Departments of Defense and State)  
http://www.tswg.gov
_		 U.S. Air Force Electronic System Center (ESC), Hanscom Air Force Base  
http://eschq.hanscom.af.mil/
_		 U.S. Army Soldiers and Biological Chemical Command (SBCCOM):  Basic 
Information on Building Protection  http://buildingprotection.sbccom.army.mil
_		 U.S. Department of Justice  http://www.usdoj.gov
 Federal Bureau of Investigation:  Terrorism in the United States reports 
http://www.fbi.gov/publications/terror/terroris.htm
 National Institute of Justice (NIJ)  http://www.ojp.usdoj.gov/nij
 Office of Domestic Preparedness (ODP)  http://www.ojp.usdoj.gov/odp
 U.S. Marshals Service (USMS)  http://www.usdoj.gov/marshals
The Infrastructure Security Partnership (TISP)  
http://www.tisp.org
Founding Organizations
_		 American Council of Engineering Companies (ACEC)  http://www.acec.org
_		 The American Institute of Architects (AIA), Security Resource Center  
http://www.aia.org/security
_		 American Society of Civil Engineers (ASCE)  http://www.asce.org
 Architectural Engineering Institute (AEI) of ASCE  
http://www.asce.org/instfound/aei.cfm
 Civil Engineering Research Foundation (CERF) of ASCE  http://www.cerf.org
 Structural Engineering Institute (SEI) of ASCE  http://www.seinstitute.org
_		 Associated General Contractors of America  http://www.agc.org
_		 Construction Industry Institute  http://construction-institute.org
_		 Federal Emergency Management Agency (FEMA)   http://www.fema.gov
 Building Performance Assessment Team http://www.fema.gov/mit/bpat
 Human Caused Hazards  http://www.fema.gov/hazards
 Mitigation Planning  http://www.fema.gov/fima/planning.shtm
_		 Federal Facilities Council  See National Academy of Sciences 
_		 National Institute of Standards and Technology (NIST), Building and Fire 
Research Laboratory  http://www.bfrl.nist.gov
_		 Naval Facilities Engineering Command  http://www.navfac.navy.mil
 Naval Facilities Engineering Service Center (NFESC), Security Engineering 
Center of Expertise ESC66  http://atfp.nfesc.navy.mil
_		 Society of American Military Engineers (SAME)  http://www.same.org
_		 U.S. Army Corps of Engineers  http://www.usace.army.mil
 Blast Mitigation Action Group, U.S. Army Corps of Engineers Center of 
Expertise for Protective Design  http://bmag.nwo.usace.army.mil
 U.S. Army Corps of Engineers, Electronic Security Center  
http://www.hnd.usace.army.mil/esc
 U.S. Army Corps of Engineers, Protective Design Center  
http://pdc.nwo.usace.army.mil
Selected Member Organizations
_		 Air-Conditioning and Refrigeration Institute, Inc.  http://www.ari.org
_		 Air Conditioning Contractors of America  http://www.acca.org
_		 Airport Consultants Council  http://www.acconline.org
_		 Alliance for Fire & Smoke Containment & Control  
http://www.afscconline.org
_		 American Association of State Highway and Transportation Officials 
(AASHTO)  http://www.transportation.org
_		 American Institute of Chemical Engineers, Center for Chemical Process 
Safety  http://www.aiche.org/ccps
_		 American Planning Association  http://www.planning.org
_		 American Portland Cement Alliance  http://www.portcement.org/apca
_		 American Public Works Association  http://www.apwa.net
_		 American Railway Engineering & Maintenance of Way Association  
http://www.arema.org
_		 American Society for Industrial Security International (ASIS)  
http://www.asisonline.org
_		 American Society of Heating, Refrigerating, and Air-Conditioning Engineers 
(ASHRAE)  http://www.ashrae.org
_		 American Society of Interior Designers  http://www.asid.org
_		 American Society of Landscape Architects (ASLA)  http://www.asla.org
_		 American Society of Mechanical Engineers (ASME)  http://www.asme.org
_		 American Underground Construction Association  (AUA)  
http://www.auca.org  or http://www.auaonline.org
_		 American Water Resources Association (AWRA)  http://www.awra.org
_		 Associated Locksmiths of America  http://www.aloa.org
_		 Association of Metropolitan Water Agencies  http://www.amwa.net
_		 Association of State Dam Safety Officials  http://www.damsafety.org
_		 Building Futures Council  http://www.thebfc.com
_		 Building Owners and Managers Association International (BOMA), 
Emergency Resource Center  http://www.boma.org/emergency
_		 California Department of Health Services, Division of Drinking Water & 
Environmental Management  http://www.dhs.cahwnet.gov/ps/ddwem
_		 Construction Industry Roundtable  http://www.cirt.org
_		 Construction Innovation Forum		 http://www.cif.org
_		 Construction Specifications Institute  http://www.csinet.org
_		 Construction Users Roundtable  http://www.curt.org
_		 Defense Threat Reduction Agency (DTRA)  http://www.dtra.mil
_		 Design-Build Institute of America  http://www.dbia.org
_		 Drexel (University) Intelligent Infrastructure & Transportation Safety Institute  
http://www.di3.drexel.edu
_		 Federal Highway Administration  http://www.fhwa.dot.gov
_		 Florida Department of Transportation, Emergency Management Office  
http://www11.myflorida.com/safety/Emp/emp.htm or  Florida Department of 
Community Affairs, Division of Emergency Management  
http://www.floridadisaster.org/bpr/EMTOOLS/Severe/terrorism.htm or  
http://www.dca.state.fl.us/bpr/EMTOOLS/CIP/critical_ 
infrastructure_protecti.htm
_		 George Washington University, Institute for Crisis, Disaster, and Risk 
Management  http://www.cee.seas.gwu.edu or  http://www.seas.gwu.edu/~icdm
_		 Homeland Protection Institute, Ltd.  http://www.hpi-tech.org
_		 Inland Rivers Ports and Terminals  http://www.irpt.net
_		 Institute of Electrical and Electronics Engineers, Inc. - USA  
http://www.ieeeusa.org  or  http://www.ieee.org/portal/index.jsp
_		 International Association of Foundation Drilling  http://www.adsc-iafd.com
_		 International Code Council (ICC)  http://www.intlcode.orgConsolidates 
services, products, and operations of BOCA (Building Officials and Code 
Administrators), ICBO (International Conference of Building Officials) and 
SBCCI (Southern Building Code Congress International) into one member service 
organization  the International Code Council (ICC) in January 2003.
_		 International Facility Management Association (IFMA)  http://www.ifma.org
_		 Market Development Alliance of the FRP Composites Industry  
http://www.mdacomposites.org
_		 Multidisciplinary Center for Earthquake Engineering Research  
http://mceer.buffalo.edu
_		 National Aeronautics and Space Administration  http://www.nasa.gov
_		 National Capital Planning Commission (NCPC)  http://www.ncpc.gov
 Security and Urban Design  http://www.ncpc.gov/planning_init/security.html
_		 National Center for Manufacturing Sciences  http://www.ncms.org
_		 National Concrete Masonry Association  http://www.ncma.org
_		 National Conference of States on Building Codes and Standards  
http://www.ncsbcs.org
_		 National Council of Structural Engineers Associations (NCSEA)  
http://www.ncsea.com  or  http://dwp.bigplanet.com/engineers/homepage
_		 National Crime Prevention Institute  http://www.louisville.edu/a-
s/ja/ncpi/courses.htm
_		 National Fire Protection Association  http://www.nfpa.org
_		 National Institute of Building Sciences (NIBS)  http://www.nibs.org  and  
http://www.wbdg.org
_		 National Park Service, Denver Service Center  http://www.nps.gov/dsc
_		 National Precast Concrete Association  http://www.precast.org
_		 National Wilderness Training Center, Inc.  
http://www.wildernesstraining.net
_		 New York City Office of Emergency Preparedness  
http://www.nyc.gov/html/oem
_		 Ohio State University  http://www.osu.edu/homelandsecurity
_		 Pentagon Renovation Program		 http://renovation.pentagon.mil
_		 Portland Cement Association (PCA)  http://www.portcement.org
_		 Primary Glass Manufacturers Council  http://www.primaryglass.org
_		 Protective Glazing Council  http://www.protectiveglazing.org
_		 Protective Technology Center at Penn State University  
http://www.ptc.psu.edu
_		 SAVE International  http://www.value-eng.org
_		 Society of Fire Protection Engineers  http://www.sfpe.org
_		 Southern Building Code Congress, International  http://www.sbcci.org
_		 Sustainable Buildings Industry Council  http://www.sbicouncil.org
_		 Transit Standards Consortium		 http://www.tsconsortium.org
_		 Transportation Research Board/Marine Board  http://www.trb.org
_		 Transportation Security Administration - Maritime and Land  
http://www.tsa.dot.gov
_		 U.S. Air Force Civil Engineer Support Agency  http://www.afcesa.af.mil
_		 U.S. Coast Guard  http://www.uscg.mil
_		 U.S. Department of Energy  http://www.energy.gov
    Sandia National Laboratories (SNL)  http://www.sandia.gov
    Architectural Surety Program   http://www.sandia.gov/archsur
    Critical Infrastructure Protection Initiative  
http://www.sandia.gov/LabNews/LN02-11-00/ steam_story.html
_		 U.S. Department of Health and Human Services  http://www.hhs.gov
_		 U.S. Department of Veterans Affairs (VA)  http://www.va.gov/facmgt
_		 U.S. Environmental Protection Agency (EPA), Chemical Emergency 
Preparedness and Prevention Office (CEPPO)  Counter-terrorism		 
http://www.epa.gov/swercepp/cntr-ter.html
_		 U.S. General Services Administration (GSA)  http://www.gsa.gov
 Office of Federal Protective Service (FPS) of GSA  
http://www.gsa.gov/Portal/content/orgs_content.jsp? 
contentOID=117945&contentType=1005&P=1&S=1
 Office of Public Building Service (PBS) of GSA  
http://www.gsa.gov/Portal/content/orgs_content.jsp? 
contentOID=22883&contentType=1005&PPzz=1&S=1
 Office of the Chief Architect of GSA  
http://www.gsa.gov/Portal/content/orgs_content.jsp? 
contentOID=22899&contentType=1005  and  http://www.oca.gsa.gov
_		 U.S. Green Building Councilhttp://www.usgbc.org
_		 U.S. Marine Corps Headquarters  http://www.usmc.mil
_		 U.S. Society on Dams  http://www.ussdams.org
_		 University of Missouri, Department of Civil & Environmental Engineering, 
National Center for Explosion Resistant Design  
http://www.engineering.missouri.edu/explosion.htm
_		 Virginia Polytechnic Institute and State University  http://www.ce.vt.edu
_		 Water and Wastewater Equipment Manufacturers Association  
http://www.wwema.org
The Partnership for Critical Infrastructure (PCIS) 
http://www.pcis.org    
Note:  Involved mainly with information systems and not building real property.
Government
_		 Department of Commerce Critical Infrastructure Assurance Office (CIAO)  
http://www.ciao.gov
_		 Department of Energy (DOE)  http://www.energy.gov
_		 Department of Homeland Security  
http://www.whitehouse.gov/deptofhomeland
_		 National Infrastructure Protection Center (NIPC)  http://www.nipc.gov
Private Sector
_		 Anser Institute for Homeland Security (ANSER)  
http://www.homelandsecurity.org
_		 CERT Coordination Center (CERT/CC)  http://www.cert.org
_		 Electronic Warfare Associates (EWA)  http://www.ewa.com
_		 Information Technology Association of America (ITAA)  http://www.itaa.org
_		 The Institute for Internal Auditors (IIA)  http://www.theiia.org
_		 National Cyber Security Alliance (Alliance)  http://www.staysafeonline.info
_		 North American Electric Reliability Council (NERC)  http://www.nerc.com
_		 SANS Institute (SANS - SysAdmin, Audit, Network, Security)  
http://www.sans.org
_		 The Financial Services Roundtable Technology Group (BITS)  
http://www.bitsinfo.org
_		 The U.S. Chamber of Commerce, Center for Corporate Citizenship (CCC)  
http://www.uschamber.com/ccc
Selected States and Local Organizations
_		 Association of Metropolitan Water Agencies  http://www.amwa.net
_		 The Council of State Governments (CSG)  http://www.csg.org
_		 International Association of Emergency Managers (IAEM)  
http://www.iaem.com
_		 National Association of State CIOs (NASCIO)  http://www.nascio.org
_		 National Emergency Managers Association (NEMA)  
http://www.nemaweb.org
_		 National Governors Association (NGA)  http://www.nga.org
_		 The National League of Cities (NLC)  http://www.nlc.or