"This primer introduces a series of concepts that can help building designers, owners, and state and local governments mitigate the threat of hazards resulting from terrorist attacks on new buildings. FEMA 427 specifically addresses four high-population, private-sector building types: commercial office, retail, multifamily residential, and light industrial. This manual contains extensive qualitative design guidance for limiting or mitigating the effects of terrorist attacks, focusing primarily on explosions, but also addressing chemical, biological, and radiological attacks." It "provides guidance to building designers, owners and state and local governments to mitigate the effects of hazards resulting from terrorist attacks on new buildings. While the guidance provided focuses principally on explosive attacks and design strategies to mitigate the effects of explosions, the document also addresses design strategies to mitigate the effects of chemical, biological and radiological attacks. In addition to applicability to the design of new commercial office, retail, multi-family residential, and light-industrial buildings, many of the concepts presented are also applicable to other building types and/or existing buildings." "Designing security into a building requires a complex series of trade-offs. Security concerns need to be balanced with many other design constraints". "Because the probability of attack is very small, security measures should not interfere with daily operations of the building. On the other hand, because the effects of attack can be catastrophic, it is prudent to incorporate measures that may save lives and minimize business interruption in the unlikely event of an attack."