In 2004, more than 534 million passengers took to U.S. rails (Boardman, 2005), making more than 3.5 billion trips (APTA, 2006).¹ And these estimates do not count the passengers traveling on the National Railroad Passenger Corporation (Amtrak) system, the primary intercity rail system in the United States, which totaled 25 million in fiscal year 2005 (Berrick, 2007). By comparison, as many people traverse New York’s Penn Station in a single morning as travel through Chicago’s O’Hare International Airport in about two and a half days (Freeman, 2005).

Unfortunately, recent attacks against rail and subway systems highlight the vulnerability of rail...

As illustrated by the examples provided in the previous chapter, passenger-rail systems have been attractive targets for terrorist attacks through much of the history of modern terrorism. Open and accessible by design and necessity, crowded with people, and key for the functioning of economic and daily life in the cities they serve, these systems represent both attractive and high-impact targets. Their openness and high usage also make them difficult to secure. As the attacks in Madrid and London demonstrate, attacks on rail systems can result in high casualty counts.

In this chapter, we discuss the key rail-attack threats and the...

In the previous chapter, we described the threat to rail-transportation systems and the consequences of attacks. We now turn our attention to describing the vulnerability of passenger-rail networks to the threats previously described. To do so, we introduce two new elements to our analysis. The first is initial specification of a notional rail system. We use a notional system, rather than an actual system, to illustrate the complexity of rail operations while avoiding providing any confidential details about specific rail systems in operation in the United States.

Second, we specify attack scenarios. By specifying attack scenarios, we begin to assess...

Ultimately, we want to identify security measures that will reduce terrorism risk to rail systems in the kinds of attack scenarios detailed in Chapter Three. Before we analyze the effectiveness of SIOs, we must both further describe our notional rail system and characterize security that it maintains. Thus, in this chapter, we provide a complete description of the notional rail system and define the baseline (or existing) set of security measures (and their performance) across the system. This collective set of information provides the groundwork for Chapter Five, in which we identify and assess the cost-effectiveness of different SIOs at...

DHS, the U.S. Department of Transportation (DOT), and other federal, state, and local agencies have taken some steps to enhance rail and transit security since the 9/11 attacks. They have taken these steps in partnership with the public and private entities that own and operate U.S. rail systems. The international rail community has undertaken similar efforts.

Examples of initiatives that have been implemented or considered include threat and vulnerability assessments; screening programs; public education and awareness; perimeter barriers, high-tech fencing, and lighting; intrusion-detection equipment; alternative external-communication capability for continuity of operations; increased number of uniformed and undercover patrols on light...

Given the open and accessible characteristics of rail systems, the unpredictability of terrorist attacks, the continual evolution of risk as terrorists learn and improve on their capabilities, and finite resources for security provisions, the United States faces a complex security problem that has existed for decades. This book has illustrated a process—a framework and a broad range of management considerations—for thinking through how to systematically improve the security of U.S. passenger-rail systems to help ensure maximum protection at the lowest cost.

In this chapter, we step back from the detailed analysis of protecting the notional rail system to...