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Safe Rooms and Shelters - CBR Threat Protection

A. Bhatia, B.E.

Course Outline

This course describes how to add chemical, biological and radiological (CBR) protection capability to a shelter or safe room. It also discusses air filtration, safe room criteria, design requirements, operations and maintenance, commissioning, and training required to operate a shelter or safe room.

This 3-hour course will introduce you to Chapter 3 “CBR Threat Protection” of the FEMA Publication tilted, “Safe Rooms and Shelters” (FEMA 453).

This course includes a multiple-choice quiz at the end, which is designed to enhance the understanding of the course materials.

Learning Objective

This course is intended to provide you with the following specific knowledge and skills:

Intended Audience

This course is applicable to engineers, planners, architects, construction and operations personnel, security and law enforcement agents, as well as consultants and contractors who are interested in gaining a better understanding in CBR threat protection of safe rooms and shelters.

Benefit to Attendees

This course will help readers gaining a basic understanding of how safe rooms protect people from airborne hazards. This knowledge will enable the occupants or facility managers to focus upon the actions that provide the highest degree of protection.

Course Introduction

A CBR safe room protects its occupants from outside contaminated air by providing clean, breathable air in two ways: (1) by trapping air inside the room and minimizing the air exchange (an unventilated safe room) and (2) by passing contaminated air through a filter to purify it as it is supplied to the room (a ventilated safe room).

This 3-hour course describes how to add CBR protection capability to a shelter or safe room.

Course Content

This course is based entirely on Chapter 3 “CBR Threat Protection” of the FEMA Publication tilted, “Safe Rooms and Shelters” (FEMA 453), which is in the following PDF document:

Safe Rooms and Shelters - CBR Threat Protection

Please click on the above underlined hypertext to view, download or print the document for your study. Because of the large file size, we recommend that you first save the file to your computer by right clicking the mouse and choosing "Save Target As ...", and then open the file in Adobe Acrobat Reader. If you still experience any difficulty in downloading or opening this file, you may need to close some applications or reboot your computer to free up some memory.

Course Summary

Buildings can provide protection in varying degrees against airborne hazards that originate from the outside. Such protection is limited, however, and effective only under certain conditions. Conversely, the hazards produced by a release inside a building can be much more severe than a similar release outside. Because buildings allow only a limited exchange of air between the inside and outside, not only can higher concentrations occur when there is a release inside or directly into a building, but inside hazards are more likely to last longer. For protection against CBR agents, the only practical protective measures are those that are continuously in-place.

Safe room actions can provide short-term (one-to-two hours in some cases) protection to the occupants and are most effective when building occupants plan and practice their actions in advance. Sheltering in-place is not the solution for every situation. However, it may be the only practical method to provide protection for residential housing or for buildings with large populations such as dormitories, auditoriums, movie theaters, and office buildings.

Although the primary reason to shelter inside buildings is to increase protection, these actions also provide emergency responders with the time they need to control or contain the release and coordinate evacuation strategies.


Once you finish studying the above course content, you need to take a quiz to obtain the PDH credits.

DISCLAIMER: The materials contained in the online course are not intended as a representation or warranty on the part of PDH Center or any other person/organization named herein. The materials are for general information only. They are not a substitute for competent professional advice. Application of this information to a specific project should be reviewed by a registered architect and/or professional engineer/surveyor. Anyone making use of the information set forth herein does so at their own risk and assumes any and all resulting liability arising therefrom.