The Noise Mapping Toolbox

Tiling helps even with mid-size projects like this Lden map of road traffic for the city of Backnang, home to SoundPLAN's development team.

The scope and scale of noise mapping projects

Noise Mapping projects have a huge range in scope and scale! Industrial complexes can have small scale projects to determine the 85 dB contour line in a plant so workers know where to use hearing protection; architects determine what type of windows are required for a hotel; road designers attempt to minimize the impact of a planned road; and country wide noise maps record the overall noise situation. The graphics to the left show some of the noise maps created for different types of noise mapping projects. Small and medium size projects can be made with all data in a single file or they can be structured in accordance to planning variant or topic. Bigger projects should be structured geographically, which requires the Tiling approach of the Noise Mapping Toolbox!

All of SoundPLAN's noise maps depict noise levels in a straightforward way using colored contour lines and facade dots according to a user set scale. The noise maps in the middle and at the bottom show other ways of presenting the results. If the investigation goal is to find the best route for a new road, comparing difference maps to the status quo is one possibility, and showing conflicts where the noise levels exceed the noise limit for a given area would be another way of showing results. Mapping conflicts is part of the Noise Mapping Toolbox.

The bottom picture was taken from the country-wide train noise map of Germany. This noise map depicts the noise levels for a very large area - so large that individual buildings can hardly be identified using the scale this noise map was drawn. Another way to depict the noise problems would be to tally the number of residents exposed to specific noise levels. This "Hot Spot" presentation is also possible with the Noise Mapping Toolbox.

Tiling

Regardless of the amount of RAM a computer has, very large projects should be structured in order to make them editable. SoundPLAN uses Situations to group any number of the Geo-Files that contain the data, so you can wisely and conveniently structure a huge project so that data units can be reused without having to redo the set up or the calculation. For example, if mapping the greater New York area,  the cities of New York and Boston could be in different files, but they would still be the same project and would share the same coordinate system. This is one example how this logical structure saves time and effort. With the Tiling System it is possible to restrict the amount of data in memory at any given time. This applies for the Geo-Database, Calculations and the Graphics!

As the tile size for convenient editing may be different for processing buildings than for the import and reconciliation of a terrain model, the user can generate multiple concurrent Tiling Systems which are independent of each other. This is another way that SoundPLAN is a practical, useful tool making work easier for users.

The screen capture to the left depicts the city of Backnang. The menu shows that this project has 2 different Tiling Systems, one with a tile size of 2kmx2km and the other with tiles of 5kmx2km.

When data are loaded into the Geo-Database, the Tiling Navigator helps you re-load tiles on-line. Use the arrow keys to move the active area.

EU-Statistics of noise exposure

If you need to show authorities the number of people in your city exposed to high noise levels, then create a Facade Noise Map, load it in the Graphics and request a EU-Building table to show the statistical summary of the noise situation. SoundPLAN sums up the number of residents and the number of problem apartments/schools/ hospitals and shows how many already have noise control in place and how many feature quiet facades. This statistics is a one button solution!

SoundPLAN not only offers the statistics based on a Facade Noise Map where every resident is considered, it also allows a Grid Noise Map to generate a statistics of areas smaller than 55dB, between 55dB and 60dB, and so on as you choose what is needed for your specific projects.

Hot Spot Presentation

In noise maps of urban areas it is sometimes difficult to see where the problem zones are located. Noisy areas may be located on very narrow streets within a business district that includes apartments. SoundPLAN developed "Hot Spot" presentations specifically for situations like these so consultants could easily find, calculate and care for these areas.

The Hot Spot Presentation takes the results from a Facade Noise Calculation and superimposes a grid pattern over the city with each grid cell polling the facade noise map for the number of people exposed to excess noise within a user defined circle. This procedure guarantees that areas exceeding the noise limits get more attention. The threshold noise level and the polling radius are user definable parameters.

Mapping Conflicts

Along with the Hot Spot Analysis, SoundPLAN offers Conflict Maps to depict how many people in a neighborhood are exposed to excessive noise levels. As areas are not uniform in size, the number of people exposed is referenced as exposed persons per square kilometer. The neighborhoods colors give a good indication where the problems are within a city.

The conflict map uses the Facade Noise Map, the SoundPLAN Spreadsheet and Graphics. It offers functionality like a GIS program, but it does this with automated and internal data structures rather than exporting from the noise simulation program and importing and formatting it in the GIS software. Because this is all automated and within SoundPLAN itself, it is convenient, practical and time saving with less room for error.

(The Conflict Map as described above used to require both the Noise Mapping Toolbox and Cartography, but will soon be available with Cartography alone.)

 

The Noise Mapping Toolbox and the SoundPLAN Spreadsheet

SoundPLAN has a built in spreadsheet program that can open SoundPLAN results, add new columns and fill them with other SoundPLAN information and create other columns to be filled with user generated answers from formulas and information from other columns.

The Spreadsheet has different modes to process receivers, or buildings, or areas. To the left you see part of a table of areas that contain EU statistics area by area. To compare one area with another, use the Spreadsheet to request another result column and write a formula to divide the number of infringements (column 7) by the area size (column 3) to get the number of infringements per square kilometer. Another possibility would be to depict the percentage of people who live in noisy conditions (divide column 7 by column 4). The possibilities are endless!

In the lower part you see a spreadsheet with the open definitions part of the columns. To find how many dB a receiver is above the noise limit, simply subtract the noise value from the noise limit. In spreadsheet speak, subtract column 14 from column 20 => x20-x14.

If the noise exceeds the limit (result>0) the result is printed in red color, otherwise a "-" is shown instead of the value. The spreadsheet not only allows for formulas but also includes formatting commands.

The Spreadsheet is linked to the Graphics so that area information can be displayed as areas with a fill determined in the Spreadsheet. Buildings and receivers can be presented with the values defined in the Spreadsheet.

This combination of the Spreadsheet and the Graphics has a big advantage over the conventional work with noise modeling software as the calculation engine and a GIS to manipulate and display the data. In SoundPLAN the data are within the SoundPLAN project so once a template is made for a Spreadsheet, new variants and updates are made very quickly - no repeated export/definition in the GIS and no import/export is required. SoundPLAN's Spreadsheet speeds up and simplifies your work without needing the features of outside software.

The Spreadsheet not only has important functions for noise mapping, it can also be very helpful determining the cost for noise control as a combination of noise protection walls and noise protection windows.

 

Annoyance calculations

Showing dB values as contour maps or Facade Noise Maps is commonplace. It is, however, by no means the only way of presenting the data. Psycho-acoustic research has shown how people react to noise from different source types. The diagrams to the upper left show the connection between noise levels for road, rail and aircraft sources. You can see the number of people the noise affects. Apparently the tolerance for rail traffic is much higher than for air traffic of the same magnitude.

The EU has published formulas to determine the percentage of the population annoyed and has also set formulas to calculate the percentage of people highly annoyed. The formulas to the left can be applied to a SoundPLAN Facade Noise Map to determine how many people in each building are annoyed by different noise events.

To facilitate the Facade Noise Map at the bottom of this page, the Spreadsheet was used to open a list of all receivers in each building. Using the formula for annoyance for road traffic, a new column calculated how many residents would be annoyed by the noise. After storing the Spreadsheet and opening it in the Graphics, it was possible to create maps showing the number of people affected by specific noise types for each building.

 

Percentages of annoyed residents

The same principle as was used to show annoyance in a Facade Noise Map. The formula was applied to the area table and the sum of annoyed people was divided by the size of the area to get a clear understanding of the magnitude of annoyance in the area.

The SoundPLAN Spreadsheet is a super tool within SoundPLAN. Only the fantasy of the engineer/geographer sets a limit of what is possible in the cooperation of the SoundPLAN Spreadsheet and the SoundPLAN Graphics!

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