“If the model changes, it seems logic that limits and zones should change as well to guarantee equal protection.”
Most countries have enforcement systems in place to protect their inhabitants from aircraft noise. Aircraft noise enforcement systems provide maximum noise (annoyance) levels or contours that should not be exceeded. In many cases, these maximum values or zones are calculated based on a certain scenario that represents planned airport operations in terms of number of flights, operational concept, routes, flight schedule, etc. This scenario is fed into a noise model to calculate the noise output expressed in either noise (annoyance) levels or contours. These calculated outcomes are then set as noise limits or noise zones.
Enforcement of aircraft noise is conducted by feeding the actual air traffic into the same model to calculate the noise (annoyance) levels that have really occurred in a given time period. These actual noise levels/contours should of course not exceed the noise limits/zones.
Policy makers, engineers and professionals in the aviation field often do not perceive noise limits or zones in the same manner as the public. For Dutch policy makers, limits and zones are outcomes of a calculation made with a certain scenario and a specific model. This perception of noise limits and zones, as an outcome of a specific calculation based on a specific scenario using a specific noise model, leads to the notion that the noise limits are dependent on or connected to the scenario and the model. However, this is not always in line with the view of the public that considers noise limits and zones as fixed.
The NLR publication by Anette Kruger-Dokter and Jos Dolderman explains a general method that can be applied in different or future situations to update noise limits in a structured and transparent way to guarantee equal protection. If you require more information or help to shape an equal noise protection, please contact the author of which you will find the coordinates below.
About the author: Jos is project leader and expert in the field of environmental aircraft noise and gained extensive knowledge in this field over the last 25 years. Currently he participates in environmental impact studies for military airfields in the Netherlands. Due to his passion for aviation Jos is flying small aircraft by himself and uses his flying experience in projects whenever he can.
Questions? You can contact Jos at firstname.lastname@example.org or +31 88 5113685.