The Department of Homeland Security has issued a notice of proposed rule-making to vastly strengthen the security of the nation's rail systems in the highest-threat urban areas.

The proposed rule is part of a package of new security measures that will require freight rail carriers to ensure 100% positive hand-off of toxic inhalation hazard materials, establish security protocols for custody transfers of TIH rail cars in the high-threat urban areas and appoint a rail security coordinator to share information with the federal government, as well as formalizing the Transportation Security Administration's freight and passenger rail inspection authority.

“A toxic emission from an attack against a chemical facility or hazardous chemicals in transit is among the most serious risks facing America's highest-threat areas,” said DHS Secretary Michael Chertoff in a press statement.

The freight rail industry has begun to implement several key security measures, such as tracking and reducing the standstill time for unattended TIH freight cars in high-threat urban areas, developing site-specific security plans with access controls, and providing security training for employees. Using industry data, TSA will create a tracking system that will allow the federal government to determine the location of TIH rail cars within minutes.

Once finalized, the proposed rule will address the transport of TIH materials by rail from start to finish, including predictable standstill points and unpredictable stops during shipment. In addition, the Department of Transportation is proposing a regulation that will require railroads to analyze safety and security concerns when determining the route for a freight train carrying certain types of hazardous materials.

TSA's proposed rule was published in the Federal Register on Dec. 21 and will be open for public comment for 60 days.