1. Noise, environment and comfort

As with all means of transport, acoustics have two components: internal noise and external noise. Rail transport combines sources found in the automotive sector (equipment/infrastructure contact) and the aeronautical sector (aero-acoustic sources). For local residents, it also combines intermittent sources during the passage of a train (as with the passage of an aircraft) and more continuous sources such as road traffic in heavily trafficked suburban areas. These two remarks demonstrate the complexity of the problem, accentuated by the separation between the operator and the infrastructure manager. We'll come back to this later.

A large proportion of the population is exposed to train noise, either as local residents or users (or as railway operators or external players specializing in this field of research!)