Darko Mihajlov

Measurement and evaluation of the environmental noise levels in the urban areas of the city of Nis (Serbia).

The environmental noise level represents one of the key factors of life quality in urban areas of modern cities. A continuous monitoring of the noise levels and the analysis of results have become a necessity when we discuss a possible recovery of those areas with high levels of noise pollution, and particularly, those zones which were designed for specific activities, e.g., areas around hospitals and schools. The city of Nis, Serbia, owing to the permanent long-term noise monitoring, possesses a database containing figures related to the noise levels at relevant locations in the city, which can serve as a basis for an analysis of the change of conditions, their tendencies in the future, and recognizing factors which influence the danger of noise pollution. The paper involves an analysis of the environmental noise level collected during the previous years.

Permanent and Semi-Permanent Road Traffic Noise Monitoring in the City of Nis (Serbia)

This paper deals with the procedure of long-term road traffic noise monitoring in urban areas. For the purpose of strategic noise mapping and assessment of harmful effects of environmental noise it is necessary to determine the annual value of noise indicators, mainly by long-term measurements, which can be realized by permanent and semi-permanent noise monitoring. The permanent noise monitoring includes noise measurements of 24 hours a day, 365 days a year, while the semi-permanent monitoring typically ranges from a few days up to several weeks or months. The research described in this paper was conducted with the aim to determine adequate duration of semi-permanent monitoring of road traffic noise in the city of Nis to enable cost-effective monitoring of road traffic noise and determination of noise indicators at multiple locations with only a few noise monitoring stations. Based on the presented sets of measurement results at three locations, it can be concluded that road traffic noise monitoring with a duration of one month yields very acceptable and repeatable values for road traffic noise assessment for the three observed locations. Likewise, the semi-permanent road traffic noise monitoring with a duration of one week or only during workdays yields very usable values for the determination of annual value of noise indicators, which can be used for road traffic noise survey.

Selection of Measurement Strategy for the Assessment of Long-Term Environmental Noise Indicators Using Multi-criteria Optimization

This paper presents a methodology for determining the values of environmental noise indicators based on measurement time intervals that are considerably shorter than one year, whereby the measurement results correspond to the actual state of acoustic load at the measured location on a yearly basis, with satisfactory accuracy and precision. According to the set requirements, the optimal time interval for noise indicator measurement was selected through multi-criteria optimization by means of the PROMETHEE method.

An Example of Vibration and Low Frequency Noise Assessment for Railway Line

Reconstruction and modernization of railway section from Beograd Centar to Stara Pazova with total length of 34.7 km, provides upgrading of existing railway line with the designed speed up to 200 km/h. The paper discusses possible impacts to the environment in terms of vibration and low frequency noise during construction and exploitation of the railway line. The calculation of vibration and low frequency noise propagation and annoyance analysis were made using simulation modeling software package “VIBRA-1”.

Assessment of Environmental Noise by Harmonica Index – Case Study: The City of Niš

Noise is a very present environmental nuisance, especially in urban areas. Information on the noise environment of agglomerations over 100,000 inhabitants is now available thanks to the publication of the first strategic noise maps made for the 2002/49/EC European directive. However, it currently remains difficult to understand the environmental noise data because of the used noise indicators expressed in decibel unit, which is complicated to explain and relatively far-removed from the perception of people. Acoucité and Bruitparif, two French organizations specialized for management and organization of urban noise observatories in France, have worked on a proposal for a new index closer to the perception of people. At the end of the HARMONICA project a new environmental noise index called the Harmonica index is suggested. The Harmonica index is an adimensional index with values between 0 and 10. This is why 93% of people surveyed during the project find the Harmonica index easy to understand. According to the Harmonica index the sound environment can be assessed as quiet, noisy and very noisy. The overview of the Harmonica index, the structure of Toots software for the Harmonica index calculation and an example of application of the Harmonica index for assessment of environmental noise in the city of Niš will be given in this paper.

Acoustic Zoning and Noise Assessment

The great majority of cities in the world have resolved problem of acoustic zoning in the urban part of the city. Two approaches are usually applied in acoustic zoning: acoustic zoning of the territory in accordance with land-use where the allowed values of noise indicator are defined and acoustic zoning by preparing noise maps around dominant sources of noise in urban areas and defining land-use in relation to calculated isofonic lines. As international standard and internationally recognized methodology for preparation of acoustic zoning does not exist, the authors of this paper initiated preparation of methodology for acoustic zoning. The concept of methodology is demonstrated in this paperwork. The methodology has been applied on the City of Nis example starting from the specificity of Nis urban area as well as requests and goals that have been set and defined during sustainable planning of Nis City development. Based on defined acoustic zones and noise measurement results for five years period on the territory of Nis City, the evaluation of the condition of noise level has been done and this paperwork presents results obtained.