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thing possible is done to mitigate excessive exposure in a cost- effective manner.
Noise maps can depict noise levels in a straightforward way using colored contour lines and facade dots according to a user- set scale, so that the best option is clear. For example, the place- ment of barriers or the effect of replacing noisy machinery can be tested on the map before any investment is made.
Noise maps can be produced for a huge range of projects of pretty much any scope and scale. Projects can range from an in- dividual room to industrial complexes that need to determine the 85dB contour line in a plant—so workers know where to use hearing protection—through to country-wide noise maps to re- cord the overall noise situation.
At the levels in between, the software is widely used for a variety of types of projects, for instance, architects determining the type of windows required for a hotel or road designers attempting to mini- mize the impact of a planned road. Using the latest sound mapping software, realistic simulations can be developed. These show all the sources of noise and how it is dispersed, making it easier to estab- lish key areas for mitigation measures.
With the right noise mapping software, users have a power- ful and flexible software tool at their disposal. For instance, some versions allow users to import digital terrain models and overlay Google Maps onto plans. They even allow manipulation of the surroundings, meaning geographical features, even mountains, can be removed or altered to get a better view of the way noise travels from and in any occupational situation.
This sophisticated software is needed because noise measure- ments only show the overall level of noise, not how much noise came from any individual source. Using computer-devised simula- tions, problem areas can be isolated and tackled.
Using sound mapping software rather than measurements also means you can predict future noise levels and take pre-emptive steps to control it. When you rely on measurements, you must wait until the noise is being made, and retrofitting noise mitigation so- lutions is usually far more disruptive and expensive than planned work. The software gives you the option of developing “what-if scenarios” so that the impact of developments or activities can be assessed in advance.
With a noise map, you can accurately identify where mitiga- tion is required and how to defend against problem noise. Even a reduction of a few decibels means many consequences of noise are lessened.
The color coding used in noise maps means they can be under- stood easily by anyone, whether they have any understanding of acoustics or engineering or not. They can also be 3D and animated and so can cover any scenario, for instance, noise levels at the tops of buildings or exposure to noise from passing traffic or trains.
Making Efficient Use of Data
All of the data required can be created and stored in a single file for small and medium-sized sound maps, or they can be struc- tured according to planning variant or topic. Larger projects should be structured geographically, which requires a tiling ap- proach to allow the different layers to be examined.
There is strong support in many countries for modeling the noise of buildings, infrastructure, and transport, both at the planning stage and for existing structures. Noise mapping software and the predic-
tions it produces are now accepted as valid and an important part of the process of ensuring citizens are protected from excessive noise.
Technology is the driving force for much of the world’s econ- omy, and the way we use the vast wealth of data at our fingertips is constantly evolving. Certainly, in the arena of noise mapping, we have been able to develop significantly as computer process- ing power has expanded exponentially. Alongside this develop- ment, the vast array of data available now means that seemingly impossible tasks can be completed at the touch of a button. Long gone are the days of hand calculations and rough estimates with spreadsheets.
Who would have believed that it would be possible to map and analyze 10 years’ worth of flight information from Frankfurt Air- port in just a few easy steps? Yet that’s what was done as part of the NORAH (Noise Related Annoyance, Cognition, and Health) study, when the radar data for 10 years was uploaded and analyzed in noise mapping software at the touch of a button. The study could then show the direct correlation between the flights and the health of the children in the affected area.
The study looked at the effects of aircraft noise on cognitive per- formance among 1,090 German second graders from 29 schools in the vicinity of Frankfurt/Main Airport. Along with reading and story recall ability, phonological precursors of reading were as- sessed to look at the underlying relationship between aircraft noise and reading ability. Analyses revealed significant effects of aircraft noise on children’s reading comprehension, even though aircraft noise levels at schools did not exceed 60dB. A 10dB increase in air- craft noise was associated with a worsening result on the reading test, corresponding to a one-month reading delay.
Big Data Can Make a Big Difference
According to IBM: “Big data is changing the way people within or- ganizations work together. It is creating a culture in which business and IT leaders must join forces to realize value from all data. In- sights from big data can enable all employees to make better deci- sions.” This is certainly true for noise mapping. The more data there is, and the more accurate it is, then the better the noise map will be and the easier it will be to make important decisions.
Analyzing extensive data on the topic shows the areas most in need of noise mitigation and means that measures can be accu- rately and cost effectively targeted. Noise mapping allows flexible use of data so that any time period can be mapped and assessed.
Every noise map is unique according to its project size, geogra- phy, and objective. The largest single variable, though, is the avail- able data. The best noise mapping software contains a vast library of information on international noise standards, and noise levels from different equipment, vehicles, and surfaces. Only when you know where noise comes from, and at what level, can you take steps to alleviate it using barriers and other acoustic devices. Then you will know you are doing all you can to protect workers from the dangers of excessive noise exposure.
Arne Berndt is the owner/adviser at SoundPLAN GmbH and SoundPLAN International LLC. SoundPLAN is a leading interna- tional expert designer and provider of acoustics and air pollution simulation software for environmental modeling. Visit https://twitter. com/SoundPLANint or www.soundplan.com/noise-control.htm for information.
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