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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

Research Report and Findings: Review of Specifications and Guidelines for Rail Tunnel Repair and Rehabilitation (Report 0235)


This report addresses tunnel repairs and rehabilitation in response to the National Transportation Safety Board's (NTSB) recommendations on development of regulatory and safety standards related to tunnel egress, including a condition-based rating system and guidelines for a tunnel inventory database.

Last updated: Wednesday, November 16, 2022
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