World Traffic Noise Policies

Explanatory Information

Using the Database
This database was developed by the PIARC Technical Committee TC E.2 Environmental Considerations in Road Projects and Operations as an adjunct to the PIARC Traffic Noise Best Practice Guide. To find noise policy information in a particular country, follow the steps outlined below:
  1. Select New Roads, Upgraded Roads or Existing Roads layers to see noise policy levels for all highlighted countries (at this stage, information is only available for the highlighted countries).
  2. Select the Policy Strength layer to see colour coding of policy strength (guideline, law etc).
  3. Select a country or jurisdiction on the map and a summary of its traffic noise policy will be presented on the right.
Noise Levels
The map shows traffic noise criteria for a range of jurisdictions in terms of free field Lden levels. These levels are approximate conversions of new road criteria from the relevant policies or regulations. The conversions were made using the New Zealand Transport Agency's Noise Metrics Tool for Metropolitan Motorways.
The conversion between noise descriptors can only be approximate due to the varying structures of descriptors and due to different ways in which traffic volume varies during the day.
Traffic noise policies in some countries are not amenable to conversion to a Lden level. For example, United States of America law requires that noise barriers be designed to achieve a noise reduction between seven and ten decibels irrespective of the preceding noise level. In these cases, the Lden level is shown grey for Not Applicable.
Policy Strength
There are many types of noise policies around the world, ranging in “strength” of enforcement, from aspirational values, which are not mandatory, to limits set by law or regulation, that are expected to be achieved. The following categories of policy strength are colour coded on the map:
  • Law a legal requirement
  • Requirement a specification that is regarded as mandatory but has no legal force
  • Standard a "standard" document that is published by a standards organisation (e.g. ISO)
  • Guideline a specification that an organisation will seriously strive to achieve, but may not achieve in some circumstances
  • Aspiration a statement of what would be desirable “in an ideal world"
The distinction between the different policy strengths and how strictly they are applied can be inconsistent. The policy strengths that are shown on this web site should be considered to be indicative.

The information presented herein was provided by PIARC members but is not guaranteed to be free of error. This web page was built by James McIntosh. Its use or interpretation should be undertaken with due care. Subsequent technical committees are tasked with maintaining this database to continue to provide a valuable resource to acoustic practitioners, policy makers and the community. Please send any corrections or additions to © PIARC 2019