15:15 pm
3937 - Towards an uncertainty analysis for parametric aircraft system noise prediction
Lothar Bertsch, PhD | German Aerospace Center DLR | Germany
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Authors:
Lothar Bertsch, PhD | German Aerospace Center DLR | Germany
Beat Schäffer, PhD | Empa, Swiss Federal Laboratories for Materials Science and Technology | Switzerland
Sebastien Guerin, PhD | German Aerospace Center DLR | Germany
Parametric noise assessment in the context of low-noise aircraft design and flight procedure optimization has been around for more than 15 years. Continuous improvement of the models and the interconnection to other simulation tools allow today's models to capture the major noise sources and relevant interactions along arbitrary flights. Yet, reliable and comprehensive uncertainty analysis of the overall aircraft noise prediction process has not been available for parametric tools in the past. This paper will present ongoing work to assess the overall uncertainty of DLR‘s in-house aircraft noise simulation with PANAM, i.e. definition of a general approach to specify uncertainties on the ground noise predictions. This will allow to discuss the temporal and the spacial distribution of the uncertainties. Certain areas along a flight path are afflicted with different uncertainties than others. The impact on exposure-response relationships due to the variation in uncertainty will be discussed, i.e. the influence of varying noise source dominance along the simulated flights. Initial results of uncertainties along typical flight procedures and their impact on selected metrics are presented in this contribution.
15:30 pm
3970 - Uncertainty of calculated noise levels and its influence on exposure-response-relationship in the NORAH-project
Manfred Liepert | Möhler + Partner Ingenieure AG | Germany
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Authors:
Manfred Liepert | Möhler + Partner Ingenieure AG | Germany
Maximilian Mühlbacher | Möhler + Partner Ingenieure AG | Germany
Ulrich Möhler | Möhler + Partner Ingenieure AG | Germany
Georg Thomann, PhD | ANU Graubünden | Switzerland
Dirk Schreckenberg | ZEUS GmbH | Germany
At the end of 2015 the multidisciplinary research project NORAH was published. In this study the noise impact by air, rail and road traffic had to be determined for nearly 1.000.000 residents in order to gain dose-response-relationships. Due to the number of participants (oder: respondents) calculations of noise levels instead of measurements were conducted.
In the discussion of the relation between exposure and response it is usual to show the scattering of the response variables whereas the uncertainty of the noise levels usually is neglected. In the NORAH-project the uncertainties of the calculated noise levels were estimated for each noise source in order to show its influence on the exposure-response-relationship. The uncertainty of the relevant calculation parameters were estimated for the noise source, the transmissions path and the receiver point for each traffic noise source considering three different distance classes between source and receiver. The resulting uncertainties were then summarized for each noise source. In a second step, for aircraft noise, the influence of both uncertainties (exposure and response) on the exposure-response-relationship were examined for annoyance and reading performance.
15:45 pm
3841 - Addressing confounding by air pollution in studies of noise and health: the relationship of measured noise and ultra-fine particles
John Gulliver, PhD | Imperial College London | United Kingdom
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Authors:
John Gulliver, PhD | Imperial College London | United Kingdom
Gerard Hoek, PhD | Netherlands
Erik van Nunen | Netherlands
Paolo Vineis, Prof. | United Kingdom
David Morley, PhD | Imperial College London | United Kingdom
There is a need in studies of traffic noise pollution and health to evaluate the robustness of associations in order to distinguish the effects from other factors such as air pollution. Little is known to this end about the relationship of noise and novel pollutants such as ultra-fine particles (UFP).
We contemporaneously measured noise levels (Optimus CR:171B), UFP (TSI-3007 condensation particle counter), and manually counted vehicles, for 30 minutes on 3 occasions, at 161 sites (55 major roads, 92 background residential; 4 rural, 10 urban green space) during 2014/15, in the city of Norwich, UK.
Overall, UFP (mean = 8522) and noise (mean = 64.5 dB(A)) were moderately correlated (r = .48; p = .000). Overall correlations were not substantially different than at major roads (r = .39; p = .004; mean UFP = 11426 ; mean LAeq = 70.0 dB(A)) and in background areas (r = .32; p = .001; mean UFP = 7015; mean LAeq = 61.6 dB(A)). Vehicle counts were highly correlated with LAeq (r = .71; p = .000) and moderately correlated with UFP (r = .48; p =.000).
16:00 pm
3935 - Uncorrelated components of Noise and PM exposure give opportunities to disentangle health effects of noise and air pollution.
Luc Dekoninck, PhD | Ghent University | Belgium
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Authors:
Luc Dekoninck, PhD | Ghent University | Belgium
Dick Botteldooren, Prof. Dr. | Ghent University | Belgium
Traffic emits noise and air pollution simultaneously but the emission dynamics of noise and air pollution differ significantly. Even within the mixture of air pollutants, important differences occur. Gaseous emissions relate to fuel consumption while particulate matter emissions relate to incomplete combustion. The dispersion and propagation dynamics of noise and PM differ as well. Especially the life-time and accumulation of Ultrafine particles is, due to many removal mechanisms, very short (coagulation and wind speed). The differences in the distance to source relation for different road types (with specific dynamics) influence the spatial impact of noise, gaseous components and traffic related PM (BC/UFP). Dwellings at moderate distance of highways are highly exposed to noise but relatively less exposed to BC/UFP. The highest exposure to BC/UFP is found near dwellings close to in-city roads with high traffic dynamics while night-time noise exposure is lower compared to dwellings near highways.
A pilot experiment will illustrate these interesting features. A population based impact assessment estimates the size of these uncorrelated sub-populations.
16:15 pm
4055 - Development of a national job exposure matrix for occupational noise in the US
Richard Neitzel, Prof. | University of Michigan | United States
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Authors:
Richard Neitzel, Prof. | University of Michigan | United States
Benjamin Roberts | University of Michigan | United States
Wenting Cheng | University of Michigan | Switzerland
Bhramar Mukherjee, Prof. | University of Michigan | United States
The assessment of occupational noise exposure in the United States is challenging. While a substantial number of noise measurements is made each year through government and industry efforts, these data are not easily available to epidemiologists or occupational health researchers and practitioners. We requested and compiled measurements from government and industrial sources, as well as from the peer-reviewed literature, to create a national job exposure matrix for noise for the United States and Canada. This job exposure matrix is based on over 1.1 million noise measurements spanning 1979-2015. Using this extensive dataset, we have estimated occupational noise exposures for thousands of job titles and hundreds of industries. The tool is now accessible through a searchable website, and the entire job exposure matrix can also be downloaded. The creation of this job exposure matrix has yielded a valuable new tool for researchers and practitioners to easily and efficiently estimates noise exposures for research subjects or workers in a wide array of jobs and industries.