49 CFR Part 673 establishes definitions that apply to a rail transit agency’s (RTA) Public Transportation Agency Safety Plan (PTASP). As your agency develops its PTASP, it is important to review and understand the new definitions in Part 673 and to ensure that your agency’s practices and documentation do not conflict with them. For consistency, your agency may choose to define these terms within your PTASP based on the new language in Part 673. Of critical importance are definitions in Part 673 that have changed from the definitions specified in 49 CFR Part 659 Rail Fixed Guideway Systems; State Safety Oversight. As you review your agency’s safety management practices and develop your PTASP, FTA recommends that you pay special attention to these definitional differences outlined in the table below. FTA developed this Roadmap to provide guidance only; it is not a substitute for FTA’s regulation.