quakes and other natural disasters, although such correlations warrant further study. Similarly, the design of blast-resistant containers for aviation may be helpful for other modes of transport. The DOD has conducted much research on blast resistance materials, designs, and structures, some of which may be applicable to transportation.
There is a great deal of interest in the transportation community not only in mitigating the effects of explosions but in containing the release of chemical and biological agents. Specialized research on the dispersal of various agents within transportation environments is needed—for instance, on understanding how trains moving in subway tunnels may push contaminants within the underground system and through external vents into the streets above.23 In addition to helping devise sensor networks, such knowledge could help in the development of mitigation equipment such as ventilation barriers and filters and in informing emergency response plans.
A key to effective postevent response is the capability to communicate and coordinate the actions of firefighters, police, elected officials, and transportation agencies across numerous jurisdictions. Communication paths, equipment, and protocols must be established in advance, as part of emergency response plans, and sizeable capacity must be made available quickly without having to disrupt basic communications links. Research and development on ways to enhance emergency decision making and communications protocols and capabilities is important to the transportation community, as it is to other participants in incident response.
As noted earlier, the ability to quickly recover and reconstitute transportation services is crucial for limiting the cascading effects of terrorist attacks. This may require a range of capabilities, from the specific means to reroute traffic around the disrupted areas to well-rehearsed, regional emergency response plans that coordinate highway and public transportation systems. Restoring transportation services following an attack will also require a range of technological capabilities—for example, neutralizing agents and robots that can survey affected areas and perform decontamination, as well as tools for the rapid repair of key infrastructure elements to render them at least minimally functional.
To deter and prevent further attacks, technologies and techniques to investigate and attribute past attacks will also be needed. Catching the perpetrators