The purpose of the National Transportation Noise Map is to facilitate USDOT stakeholders, researchers, industry and the public in their efforts to track trends in transportation-related noise, by mode, and collectively for multiple transportation modes. The National Transportation Noise Map provides a basis for understanding what-if scenarios and helping policy makers and planners to prioritize noise-related transportation investments. The data allow viewing the national picture of potential exposure to aviation, highway, and rail noise. The data also allow viewing of the potential exposure at the state or county level. The National Transportation Noise Map and associated data were developed for national level analysis and includes simplified noise modeling. It is intended for the tracking of trends and should not be used to evaluate noise levels in individual locations and/or at specific times. Please visit this site for supporting documentation and data downloads.