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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Adjustment of Nationwide Significant Risk Threshold

Notice of adjustment of Nationwide Significant Risk Threshold.

In accordance with appendix D to title 49 Code of Federal Regulations (CFR) part 222, Use of Locomotive Horns at Public Highway- Rail Grade Crossings, FRA is updating the Nationwide Significant Risk Threshold (NSRT). This action is needed to ensure that the public has the proper threshold of permissible risk for calculating quiet zones established in relationship to the NSRT. This is the sixth update to the NSRT, which is increasing from 13,722 to 14,347.

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