Struggle with noise pollution on the railway

Noise level in the surroundings of traffic routes mainly depends from traffic volume, flow composition, speed of the vehicles as well as from the cross-section and road longitudinal gradient. Under higher speeds significant influence on the noise level has also tyre/road noise. Tyre/road noise depends on type and pavement condition state, specifically from the surface macrotexture. The influence of macrotexture is varying and strictly connected with the type of vehicles, tyres characteristics, frequencies of emitted noise. On the base of investigations of the rolling noise applying Statistical Pass-By method along the Polish roads the paper presents elaborated dependences and fixed values of differences between maximum noise levels under passing multiple-axle heavy vehicle and passenger car on the asphalt concrete surface, stone mastic asphalt and the surface dressing. The functional dependences between maximum rolling noise levels in the range of complete level and in the octave band spectra: 250 Hz, 500 Hz, 1000 Hz, 2000 Hz and 4000 Hz and between the surface macrotexture described by mean profile depth, and logarithm of vehicle speed and adequate nomograms were evaluated in the paper. On this base the values of differences in the levels of emitted noise from passing heavy vehicle and passenger car in function of speed and surface macrotexture were computed. The manuscript also presents how surface macrotexture and traffic flow composition have influence on equivalent noise level in the road vicinity under equal traffic volume.

Noise pollution arises as a severe problem to the community and ground transportation has highly impacted noise environment of the neighbourhood. In the present study, six stations were selected from three different locations in order to assess the traffic noise impact among residential area along Jalan Kluang, Batu Pahat. The objectives of this study focused on two main stages: (1) determination of noise indices; and (2) assessment of traffic noise impact. The noise indices such as equivalent continuous noise level (LAeq), noise level exceeded 10% (L10), 90% (L90) and the maximum noise level (LAFmax) of peak hours measurement time were determined using sound level meter (SLM) at all six stations. Besides, traffic noise index (TNI) and noise pollution level (LNP) were calculated based on the measured noise indices to expose the traffic noise impact. Overall, the result of the present study showed that residential area faces traffic noise disturbance partially whereby 50% of the stations exceeded the DOE standard which was 55dBA. Nevertheless, the residents living nearby Jalan Kluang are commonly facing traffic noise nuisance, but stations located further inside residential areas tend to have more residential background noises apart from traffic influence.

One of the biggest problem in most cities – noise emissions in the environment caused by transport. It is found that environment noise can cause not only discomfort, but it is also harmful to health. Therefore, noise emissions in the environment is topical environmental problem. In this article the vehicle noise emissions are evaluated, depending on traffic in Trakai city. At selected locations in the northern and southern parts of the city equivalent and maximum noise levels are measured. According to estimates of traffic day, evening and night, using CadnaA program, noise maps are simulated. The noise map will show noise emissions day, evening and night. Measurement have shown, that maximum noise values was near main roads. In the south of the city, near Gediminas street, equivalent sound level during daytime was 60 dB, evening 54 dB, night – 48 dB. In the north of the city, near Karaimai street equivalent sound lever during daytime was 59 dB, evening – 54 dB, night – 51 dB. The simulations generated sound level values were similar to measured, the differences between the simulated and measured values were up to 4 dB. Viena didžiausių problemų miestuose – tai vis didėjančių transporto srautų sukeliamas triukšmas ir jo sklaida aplinkoje. Yra nustatyta, kad aplinkos triukšmas gali sukelti ne tik nepatogumų, tačiau ir kenkti sveikatai. Todėl triukšmo sklaida aplinkoje yra aktuali aplinkosaugos problema. Šiame straipsnyje vertinama transporto triukšmo sklaida, atsižvelgiant į transporto srautus Trakų mieste. Parinktose vietose šiaurinėje ir pietinėje miesto dalyse yra išmatuojami ekvivalentiniai ir didžiausieji garso lygiai. Pagal apskaičiuotus transporto srautus dienos, vakaro ir nakties metu, naudojant CadnaA programą, sudaromas triukšmo sklaidos žemėlapis. Žemėlapiuose pavaizduota triukšmo sklaida dienos, vakaro ir nakties metu. Atlikus matavimus, buvo nustatyta, jog didžiausios triukšmo vertės yra prie pagrindinių kelių. Pietinėje miesto dalyje, šalia Gedimino gatvės, ekvivalentinis garso lygis dienos metu siekia 60 dB, vakaro – 54 dB, nakties – 48 dB. Šiaurinėje miesto dalyje didžiausi triukšmo lygiai buvo prie Karaimų gatvės, kur ekvivalentinis garso lygis dienos metu siekė 59 dB, vakaro metu buvo 54 dB, nakties metu 51 dB. Atlikus modeliavimą, gautos garso lygio vertės buvo panašios kaip ir išmatuotos, skirtumai tarp sumodeliuotų ir išmatuotų verčių buvo iki 4 dB.

A maximum noise-level prediction method for high-speed railways in China: A case study using the Baiyun campus of Guangdong polytechnic normal university

This paper presents the results obtained from environmental noise measurement at selected locations in Ilorin metropolis. Forty-two (42) different locations throughout Ilorin were selected to establish background noise level and dominant noise sources at these selected locations. Noise level measurements and analysis for the locations were based on the noise descriptors LAeq, L1, L10, L50, L90, and LD. The results from comparative study indicated that the equivalent noise level (LAeq) and peak noise level (L1) have the highest and lowest values at road junctions/busy roads (86 dBA, 88 dBA) and low density residential areas (46 dBA, 63 dBA) respectively. The background noise level (L90) has the highest and lowest values at passengers loading parks (73 dBA) and low density residential areas (34 dBA) respectively. The result of this study shows that the major source of noise in Ilorin metropolis can be attributed to traffic noise. Other intrusive noise sources include noise from record player, electric generators, and hawking with loud speakers. Based on the recommendations of CEOH, WHO and HUD, only 6 locations out of 42 are under normally acceptable situation while the noise levels of other areas are not acceptable. Noting the noise emission standards, technical control measures, planning and promoting the citizens awareness about the high noise risk may help relieve noise problem in the metropolis. These data are useful as reference and guideline for future regulations on noise limit to be implemented for urban areas in Nigeria

Computational simulation and analysis of double-swept blade in BVI noise reduction

Background . Noise pollution is a burden exerting a harmful and irritating effect on human health. Children are particularly sensitive to noise burden. In this connection, it is especially important to control the noise pollution level in public education organizations where children spend significant time. Objective . The study is aimed at determining objective and subjective parameters of noise pollution in public education organizations based on the analysis of data obtained by measuring noise levels in school campuses in Saransk and directly in classrooms, as well as by questioning the teachers of these schools. Methods . The measurement of noise burden was carried out in 10 schools using the noise and vibration level meter “Assistant” with class I accuracy. Noise measurements in school campuses and classrooms were performed in accordance with the GOST 23337-2014 requirements. Assessment of results was conducted in accordance with sanitary standards 2.2.4/2.1.8.562-96 “Noise in the workplace, residential and public buildings and housing developments”. Results . Based on noise measurement results, the highest noise levels were found in school № 2 (65.5 dBА on the campus, 51.2 dBA in the classroom) which is located in the center of a traffic interchange. The lowest noise parameters were found in school № 35 (45.2 dBА on the campus, 37.7 dBА in the classroom) which is located in the residential quarter quite far away (242-321 m) from the main source of noise, the motorway. Conclusion . Study results attest that maximum noise levels at school campuses do not exceed the permissible exposure limit of 70 dBA. In all schools noise values conform to the noise standards (maximum sound pressure level in classrooms did not exceed 55 dBA).

Environmental noise is a significant public health issue, particularly in rapidly urbanizing cities where commercial activities contribute to elevated noise pollution. Despite its numerous implications, few studies have focused on noise levels in commercial environments in developing countries. This study aims to fill this existing gap by assessing background noise levels in four commercial areas of Freetown, Sierra Leone: Aberdeen Market, Godrich Street, Jui Junction, and Sani Abacha Street. Using a calibrated handheld sound level meter, measurements were taken during daytime, evening, and nighttime periods over one week. Noise levels were analyzed using the day-evening-night equivalent continuous noise level (Lden) and statistical methods to assess compliance with World Health Organization (WHO) guidelines. Results revealed that all areas exhibit average noise levels above the WHO recommended limit of 70 dBA during daytime and evening hours, with Godrich Street and Aberdeen Market exhibiting the highest average daytime noise level (95.35 dBA) and the lowest average nighttime noise level (53.05 dBA) respectively. Godrich Street recorded the highest Lden value and shortest allowed exposure of 93.34 dBA and 1.17 hours respectively, indicating the most significant risk of prolonged exposure. Recommendations include creating designated quiet zones tailored to local commercial layouts, stricter enforcement of noise regulations, public awareness campaigns on hearing protection, and regular noise monitoring to guide urban planning. This study provides crucial insights for mitigating noise pollution and improving urban sustainability in developing nations.

Forty representative roadway locations were randomly selected for monitoring traffic flow and noise levels. At local streets, equivalent noise level (Leq) ranged between 56 to 71; at collector streets traffic areas 70 to 83; at arterial roadway 75 to 86 and at freeway roadway areas 75 to 88 dBA during day and night time respectively. Consequently, the level of noise pollution from traffic even at the present time, exceed the outdoor standard limit by a significant margin. The present unplanned growth of residential and commercial infrastructures will adversely affect the level of traffic congestion and noise pollution in Metropolitan Kuwait. There is an urgent need for improving the urban public’s education concerning daily travel and its impact on both the economy and the environment of the state, as well as on the welfare and health of the urban residents. Maximum policy makers’ attentions should be given to promote the use of public transit and non-motorised modes of urban travel in Kuwait.

Equivalent magnetic noise levels at 1 Hz of three GMI samples have been experimentally determined for different excitation conditions related to both dc current and ac excitation amplitude. These three wires or cylindrical-shaped samples are from the exact same alloy composition and obtained from the same fabrication process. The only difference is their diameter which are 80 im, 100 im and 120 im, since this parameter has been identified as an important factor involved in GMI low frequency noise level. Indeed, from the recently proposed model, briefly reminded here, the equivalent magnetic noise level should decrease with the square of the wire diameter. These low frequency equivalent magnetic noise level measurements have been conducted with coherence measurements showing that the main noise source responsible of this noise level is the intrinsic noise of the GMI sensor. Obtained results have then been compared to the expected noise level from the theoretical model, showing a relative good agreement, validating the behavior regarding wire diameter.

Urbanization and population growth, as well as the movement of diverse vehicles on urban roadways, all contribute to excessive noise in the urban acoustic environment. Annoyance, cardiovascular disease, dementia, hypertension, stress, sleeping problem, irritation, hair‐fall, headache, are the most common reported problems due to traffic noise exposure. The “Structural Equation Modeling–Artificial Neural Network Model” was used in the current study to predict traffic noise induced annoyance among 100 vendors whose shops are located from Khandagiri to Baramunda along the National Highway 16 of the smart city Bhubaneswar Odisha. Due to the movement of large number of heavy vehicles as well as medium and light weight vehicles, these roadways remain noisy throughout the day. Moreover, the annoyance questionnaire was developed in compliance with ISO/TS 15666 criteria for assessing annoyance level. The combination of SEM and ANN is rarely seen in acoustics, especially in noise studies. However, in this study, both SEM and ANN are used to predict annoyance using various noise indices. Moreover, the SEM model revealed a significant association between “Equivalent Noise Level” (Leq) and annoyance (p‐value = 0.031), “Minimum Noise Level” (LMin) and annoyance (p‐value = 0.049), “Background Noise Level” (L90) and annoyance (p‐value = 0.047), “Noise Pollution Level” (NPL) and annoyance (p‐value = 0.038). These associations indicate that Leq, LMin, L90 and NPL have a significant effect on annoyance. Furthermore, the PLS algorithm output from the measurement model verified a 47 percent variance in annoyance level. The ANN model confirmed that NPL is the most significant predictor of noise annoyance, followed by LMin, Leq, and L90. Moreover, the ANN model can predict annoyance with an accuracy of 68.5 percent.

Traffic noise has been recognized as a serious threat to the quality of life in most industrialised nations. Klang valley is rapidly emerging as industrialized and urbanized city and has started facing severe noise pollution problems. Urban noise quality assessment is studied in three residential areas; Desa Tun Razak, Kinrara Court and Taman Sentul Utama. Noise pollution indices of L10, L50, L90, Lmax and Lmin as well as equivalent continuous noise level (Leq) were measured for all dwellings. Noise indices results illustrate that Desa Tun Razak recorded the highest values of noise levels among three studied sites. Results also indicate that the highest Leq of 75.7 dB(A) was observed in Desa Tun Razak followed by 74.3 dB(A) in Kinrara Court, and 72.1 dB(A) in Taman Sentul Utama. The noise assessment study clearly reveals the alarming condition of noise pollution in residential areas of Klang Valley as the noise level measured exceeded permissible limit by WHO and Malaysia Guidelines.

The Noise Levels database has been developed at the Canadian Centre for Occupational Health and Safety for the computerized information system, CCINFO. The database documents measured noise levels from a broad spectrum of industrial settings. Industrial hygienists, noise control engineers, researchers, health and safety committee members, and appropriate government agency personnel are the main intended audience. Noise Levels is a textual‐numeric ‘source’ database of direct measurements, although bibliographic citations are also provided. The data for Noise Levels is gathered from both published and unpublished sources. Each record provides explicit information on the noise source (for example, piece of equipment), the industry, operation associated with the noise production, and the occupational categories. Additional information is provided on the type of noise, exposure duration per day, the presence of engineering controls, and the use of ear protection. Measurement data consists of one or more of the following: Sound Pressure Level (SPL) in dB(A), Time Weighted Average (TWA), Equivalent Continuous Noise Level (ECNL), and the octave band analysis. The primary goals of the database are to encourage sharing of industrial noise data and to promote standardized reporting of noise measurements.

Diwali (or Deepavali) is one of the most glamorous cultural festivals in India. It is the festival of light and is celebrated every year during the month of November with great firework displays. Burning of different fireworks generates acute noise and toxic fumes, which lead to noise and air pollution in the environment. The excessive use of fireworks aggravates the level of air and noise pollution and causes adverse impacts on human health. The present paper assesses the noise pollution and air pollution during Diwali in Sambalpur City, one of the premier cities in the western part of Odisha State in Eastern India. The noise level is measured on Diwali day and is compared with that on normal days. Similarly, air quality is measured on Diwali day and compared with that on normal days (pre-Diwali and post-Diwali). The average equivalent continuous noise levels (L eq) and noise pollution levels have increased in all areas on Diwali compared with those on non-Diwali days. It is also observed that there is a significant rise of air pollutants, total suspended particulate matter, PM10, PM2.5, sulfur dioxide (SO2) and nitrogen dioxide (NO2) in ambient air due to burning of crackers in Diwali.

In Vilnius and in other bigger towns the noise generated by mobile sources accounts for up to 90 % of the total noise level in a town. A high noise level is detected at motor vehicle parking lots. To measure this noise level, testing was carried out at guarded parking lots which were divided into certain types. One lot of each type was chosen for testing. The number of measuring spots was conditioned by the size of a lot. The data obtained during testing reveal that the highest noise level is generated not at a parking lot but on a nearby street. Such conclusions are proved by the results of testing carried out at a parking lot on E. Sugihara street. Although this lot parks over 100 vehicles, the equivalent noise level is 47 dBA. Basing on the testing data, the numeral simulation of the noise dispersion in areas in the vicinity of parking lots has been run with the help of the numeral simulation software IMMI.