WASHINGTON -- Freight railroads have agreed to rely exclusively on federal safety response recommendations, rather than their own guidelines for accidents involving dangerous chemicals, drawing praise from New Jersey lawmakers who sought that change after a Conrail derailment caused a toxic spill in Paulsboro in 2012.

The shift, the lawmakers said, will help eliminate confusion that might result from differences in federal recommendations and railroad protocols, and ensure that federal standards are used in the event of spills. The guidelines give emergency responders information about fire risks, immediate steps to respond to a spill and evacuation distances, among other information.

"When a train accident happens and every second counts, it makes no sense to have two sets of emergency response information on board — especially if that information is contradictory," said Sen. Bob Menendez (D., N.J.).  "At best, it's confusing for first responders.  At worst, less protective information could result in serious consequences for public health and human life."

Menendez and U.S. Rep. Donald Norcross (D., N.J.) had co-sponsored a bill to require railroads to follow the federal guidelines. Sen. Cory Booker (D., N.J.) also hailed the changes. Though the measure has not passed, the railroads voluntarily took that step this summer.

The Association of American Railroads, which represents major freight carriers, voted in August to discontinue its Hazardous Materials Emergency Response Database and rely instead on the federal Emergency Response Guidebook, hoping to erase any discrepancies, according to a new Government Accountability Office report. The inconsistencies in federal guidelines and the railroads' own protocols had drawn criticism from the National Transportation Safety Board in the aftermath of the Paulsboro spill, and led the agency to recommend that rail guidelines be at least as protective as the federal standards, which are not mandated.

The GAO said those changes will also trickle down to smaller freight railroads that depended on the industry's database.

While the two standards provided mostly similar guidance in the case of spills, in some cases there were differences.

For example, for the chemical spilled in Paulsboro, vinyl chloride, railroad standards called for a half-mile evacuation in case of fire. Federal guidelines said the evacuation should be double that, a mile.

Nearly 700 Paulsboro residents were eventually evacuated from their homes.

The GAO found inconsistent response recommendations for eight of the 72 chemicals it reviewed.

"Adoption of this safety measure provides uniformity for first responders on scene when rail emergencies happen," Norcross said in a statement issued by Menendez's office.

A spokesman for the Association of American Railroads, the freight group, wrote in an email that it made the change to "eliminate any potential discrepancies" between the federal guidebook and their own supplemental information. "The U.S. freight rail industry is continuously looking for ways to be even safer and stay in step with local first responders," wrote spokesman Ed Greenberg.

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