This manual provides direction for the preparation of noise and vibration sections of environmental documents for mass transportation projects. The manual has been developed in the interest of promoting quality and uniformity in assessments. It is expected to be used by people associated with or affected by the urban transit industry, including Federal Transit Administration (FTA) staff, grant applicants, consultants and the general public. Each of these groups has an interest in noise/vibration assessment, but not all have the need for all the details of the process. Consequently, this manual has been prepared to serve readers with varying levels of technical background and interests. It sets forth the basic concepts, methods and procedures for documenting the extent and severity of noise impacts from transit projects.