An environmental noise impact assessment is a study typically required by the municipality or other territorial authority if a production facility or infrastructure is to be installed on the relevant geographic basin.
It can also be applied for as part of a Single Environmental Authorization (AUA) or Integrated Environmental Authorization (IEA) procedure, even in a prospective form, that is, before the work is carried out.
This study is regulated by the Noise Pollution Framework Law No. 447 of October 26, 1995 and covers all manufacturing activities and public establishments that have noisy equipment.

Law no. 447/95, in Art. 8(2) requires that a noise impact report must be produced whenever:

• you decide to build, modify or upgrade a construction work (among those that are listed in the law);
• you intend to start a new productive, commercial or recreational activity;
• you submit an application for building permits for new facilities, infrastructure of production activities or commercial services;
• a public agency or municipality makes a request.

Noise impact assessments do not have a deadline!

Noise impact assessments do not have an expiration date, so they do not need to be updated periodically, but they must generally be re-drafted whenever a decision is made to make an expansion to the activity, a modification, or to insert a new noise source that may result in a change in previously calculated or surveyed noise emission levels.

The noise impact assessment can only be carried out by a Technician Competent in Environmental Acoustics, a professional figure recognized by the Region and qualified to carry out phonometric surveys, and involves the following steps:

• inspection of the area of interest;collection of general information about the new activity or existing activity;
• Performance of instrumental measurements by sound level meter;
• Evaluation of compliance with prescribed limits (legal limits);
• Drafting the final document.

The final document should specifically contain the concluding judgment of the investigation carried out.

In the event that a comparison with the legal limits in that area reveals that they have been exceeded, it is necessary to establish a remediation plan by promising the authorities to decrease or eliminate emissions so as to fall within the current limits. This remediation plan should be present within the report.

For this reason, the report should contain the measures necessary to contain the noise level within the values allowed by law.

The noise remediation plan, in particular, should provide the following information:

• The technical reasons because of which it was necessary to identify measures to contain noise levels, with reference to the sound sources responsible for exceeding the limits;
• the mitigation measures chosen, with a technical description of the remediation measures and the sound-absorbing characteristics of the materials to be used;
• The estimated reduction in sound levels following the implementation of the planned interventions.