Ambientes laborales de ruido en el sector minero de la Comunidad de Madrid : clasificación, predicción y soluciones

El ruido es uno de los contaminantes físicos de mayor presencia en el sector de la minería a cielo abierto así como en sus industrias auxiliares. Diferentes instituciones internacionales han tratado de una u otra forma el problema del ruido laboral, tanto desde el ámbito político y legislativo, como es el caso de la Unión Europea, como desde un punto de vista descriptivo y divulgativo, caso de la Organización Mundial de la Salud. Actualmente se conocen numerosos efectos negativos producidos por la exposición al ruido, sobre todo en lo relativo al sistema auditivo. Aunque existen evidencias de la existencia de otros muchos efectos, algunos de ellos todavía no se encuentran caracterizados de forma precisa. Debido a la importancia que dichos efectos tienen sobre la salud y el bienestar de las personas, se hace necesario desarrollar mecanismos que estudien y planteen soluciones preventivas sobre estas cuestiones. En el año 2003 la Unión Europea aprobó una nueva Directiva (2003/10/CE) relativa a la exposición de los trabajadores a los riesgos derivados de los agentes físicos (ruido). Esta Directiva fue transpuesta al ordenamiento jurídico español mediante el Real Decreto 286/2006. Las particularidades y dificultades que presentan las actividades mineras y constructivas, respecto a otras actividades industriales, hacen compleja la aplicación de las diferentes normativas de ruido laboral. En esta investigación se han estudiado los niveles de ruido a los que se encuentran expuestos los trabajadores de los sectores de la minería y de la fabricación de cementos de la Comunidad de Madrid, utilizando diferentes técnicas y procedimientos de medida y comparando los resultados con los valores límite expresados en las diferentes legislaciones en vigor. Por otra parte, se ha desarrollado un algoritmo de estimación del tiempo óptimo de medida, que permite la evaluación de los niveles de exposición sonora mediante la realización de medidas con medidores personales de exposición sonora, y entre otras aportaciones, se ha analizado la contribución de las diferentes variables a la incertidumbre total de las medidas, que serán de utilidad para la valoración de la exposición al ruido en el trabajo en este sector productivo

Room flanking sound transmission assessment using a vibration probe

Most of airborne sound insulation test are performed according to certification standards, and only deal with sound pressure as a variable to estimate insulation. Besides, standards are aimed to provide direct path insulation, so one gets no idea regarding flanking paths. Without data from every path involved in sound transmission, a proper insulation designing stage can became mistaken and unfinished

Tourist Influence on Nightlife Noise

Although environmental noise from entertainment and leisure activities is causing a growing number of complaints from EU population, this noise issue is not covered by the current EU initiatives on environmental noise management. This noise problem is difficult to tackle strategically and technically – no specific standards have yet been established for measurements, methods and indicators, and the practical remedies are still limited. This paper reviews nightlife noise and more specifically how the presence of tourists influences the variation of the noise. Several case studies were conducted in some Spanish locations by the seasonal tourist incursion, mainly in the summer months. Variations in the nightlife noise in recreational zones during the weekends and “working days” are compared. This research also discusses data from different years and seasonal periods and reinforced with data obtained through surveys specifically designed for foreign tourists. These surveys reveal practical information about how tourists perceive noise, and their behaviour and reactions to it. Those data could be useful for Environmental Noise Authorities to develop noise action plans, as recreational noise is a source not considered when noise mapping by means of using simulation techniques

Noisy Environments: the Influence on Basic Cognitive Processes

The attention processes in people is affected by background noise produced by many different sources. Beta (13-30Hz) and Theta (4-7 Hz) waves are directly related to attention and memory processes. Volunteers were asked to perform an attention test with and without background noise and their cerebral activity was recorded through electroencephalography (EEG). Results shows significant decreases in both beta and theta frequency bands (beta 13-30 Hz and theta 4-7 Hz) under background noise exposure. The attentional improvement is related to increases of the beta and theta waves, and we have observed that those decreases are directly related to a lack of attention caused by the exposure to background noise

E-comparisons: A new approach to round robin tests for environmental noise assessment in transport infrastructures

The increasing importance of pollutant noise has led to the creation of many new noise testing laboratories in recent years. For this reason and due to the legal implications that noise reporting may have, it is necessary to create procedures intended to guarantee the quality of the testing and its results. For instance, the ISO/IEC standard 17025:2005 specifies general requirements for the competence of testing laboratories. In this standard, interlaboratory comparisons are one of the main measures that must be applied to guarantee the quality of laboratories when applying specific methodologies for testing. In the specific case of environmental noise, round robin tests are usually difficult to design, as it is difficult to find scenarios that can be available and controlled while the participants carry out the measurements. Monitoring and controlling the factors that can influence the measurements (source emissions, propagation, background noise…) is not usually affordable, so the most extended solution is to create very effortless scenarios, where most of the factors that can have an influence on the results are excluded (sampling, processing of results, background noise, source detection…) The new approach described in this paper only requires the organizer to make actual measurements (or prepare virtual ones). Applying and interpreting a common reference document (standard, regulation…), the participants must analyze these input data independently to provide the results, which will be compared among the participants. The measurement costs are severely reduced for the participants, there is no need to monitor the scenario conditions, and almost any relevant factor can be included in this methodolog

Spatial Interpolation contribution to noise maps uncertainty

Noise maps results are usually presented as contour graphs or isophone curves, which describe the sound levels as functions of spatial location. These maps are added to Geographic Information Systems (GIS), allowing sound level evaluation as a function of the continuous coordinates x and y, for a given height above ground. Although the outcome of the system is a continuous variable, the calculations that allow its evaluation are obtained in discrete points that form a calculation grid, which is created by the application of spatial sampling techniques. Using spatial interpolation tools, values are assigned to the locations in which measures or calculations have not been performed. The application of sampling and interpolation techniques (the type of grid, its density, the interpolation algorithms…) contributes to the uncertainty of the results. This paper describes a calculation method to quantify the uncertainty associated to the spatial sampling and interpolation process. We also propose a revision of the classical meaning of noise mapping uncertainty, taking into account the final application of the results

Uso de redes neuronales artificiales en la valoración económica de ruido de tráfico

Este estudio presenta un método alternativo que valora económicamente la disposición a pagar para reducir la molestia que ocasiona el ruido de tráfico, a través de un conjunto de redes neuronales artificiales. El modelo es capaz de predecir un rango de pago a partir de: un estudio de percepción subjetiva del ruido y sus efectos en la salud, niveles objetivos de exposición al ruido de tráfico obtenidos a partir de un modelo predictivo, características demográficas, socioeconómicas y las geográficas del lugar de residencia de los encuestados. Los resultados de este método han sido comparados con los resultados de un modelo econométrico probit ordenado, obteniendo un desempeño superior al 87.5% en términos del error porcentual promedio en los rangos de predicción. El estudio demuestra su capacidad de generalización y puede ser utilizado como una herramienta de valoración en la gestión del ruido urbano

Influencia del ruido de fondo en ambientes universitarios sobre los procesos cognitivos básicos

En este trabajo, se presenta un estudio cuyo objetivo fue determinar la influencia del ruido de fondo producido dentro de instalaciones universitarias sobre procesos cognitivos básicos tales como: la percepción y la atención. Se realizaron grabaciones de ruido de fondo en aulas de clase, bibliotecas, etc., para luego exponer a estudiantes universitarios a estos ambientes sonoros. Se registró la actividad cerebral a través de electroencefalografías (EEG), estudiando los cambios en las bandas de frecuencia relacionadas con procesos atencionales (beta 13-30 Hz. y theta 4-7 Hz.). Los resultados preliminares aquí presentados, muestran un decremento en estas bandas al exponer a los voluntarios a ruido de fondo. Así mismo, se aplicó una prueba psicométrica para determinar cambios en la atención. Los resultados obtenidos en esta prueba, no permiten relacionar directamente la influencia del ruido de fondo sobre los procesos atencionales

Preliminary test to characterize the soundscape of the Plaza Mayor in Madrid

This paper is a first step of a research about the analysis of the richness of the existing sounds in the Plaza Mayor, due to the old and traditional shops and bars under its porticoes together with the huge daily affluence of people. In this paper we study the sound preferences of the salesmen and bar tenders at those traditional shops. These sound preferences include particular sounds, time of occurrence and date of specific annoying and pleasant sounds perceived at the square and the shops surrounding it. To carry out this study, several noise level measurements and socio-acoustic surveys were held. We will also try to correlate sound preferences and annoyance with noise levels of specific events existing at this particular square

Methodology for characterization, evaluation and optimization of acoustic environments

Currently we are working on methodologies to characterize, evaluate and optimize acoustic environments with different approaches. One methodology is based on the evaluation of temporal energetic behavior of acoustic environment through the use of parameters associated with the autocorrelation function (ACF). In this case the main objective is to verify the variability of the temporal behavior of urban acoustic environment depending of sounds sources that are part of them. We evaluate the temporal energetic behavior in 10 urban acoustic environments using ACF in two main cities, Brasilia (Brazil) and Bogotá (Colombia). The second methodology is based on the design of an experiment to improve and optimize acoustic environments on the basis of the auditory subjective experiences of the people. It has been designed a LabVIEW application for psychoacoustic laboratory tests to evaluate the subjective perception of people. The main objective is to evaluate how adding sound signals in acoustics environments with traffic noise couls improve the experience of the users