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Urban Soundscape and Noise Pollution: An Introduction
Published in Uday Chatterjee, Arindam Biswas, Jenia Mukherjee, Sushobhan Majumdar, Advances in Urbanism, Smart Cities, and Sustainability, 2022
Tallal Abdel Karim Bouzir, Hamza Benacer, Djihed Berkouk, Uday Chatterjee, Sushobhan Majumdar
Noise measurement is the classic method for studying a sound environment; it is the operation that allows us to measure the sound level in dB using a sound level meter in accordance with one of the measurement standards (Yang, Aletta, and Kang 2021). We can cite for example, the NF S 31-010, where the sound level meter must be placed at a minimum distance of 2 meters from all reflecting obstacles, and at a height of 1.5 meters from the ground, as there is the NF S 31- 130 which recommends placing the sound level meter at a height of 5 meters and at a distance of 2 meters from the facades (V. Rozec and Moch 2000; Valérie Rozec and Rumeau 2000; Sémidor, Torgue, and Beaumont 2010). But the result of this method does not represent the soundscape as it is perceived by the users of the spaces, and the number in decibels cannot represent the soundscape as a whole especially the subjective part that depends on the feelings of human beings. This is why other methods are proposed by other researchers (Aumond et al. 2018).
Structural Design
Published in S.V. Kulkarni, S.A. Khaparde, Transformer Engineering, 2017
Noise levels are commonly measured in decibels (dB) by comparing the pressure generated by the noise source with some standard level. The noise level is measured on A-weighted scale which closely follows the sensitivity of the human ear. There are basically two methods for noise measurement: a sound pressure measurement technique and a sound intensity measurement technique. The details of test methods and acceptable test environment conditions are given in IEC standard 60076-10 (Determination of sound levels, First Edition, 2001). Sound pressure is a scalar quantity and requires simple instrumentation.
Noise and Vibration
Published in Charles E. Baukal, Industrial Combustion Pollution and Control, 2003
Figure 10.11 shows a commonly used device for measuring industrial noise. A noise measurement system consists primarily of some type of microphone to receive the sound, some type of transducer to convert the sound waves into a usable signal, typically digital, and a meter to convert the signals into the proper weighting system and to display and record the signals. Figure 10.12 shows an engineer measuring sound from a flare.
Simulation-based framework for optimal construction equipment allocation considering construction noise emissions
Published in Journal of Asian Architecture and Building Engineering, 2023
Hoyoung Baek, Seunghoon Jung, Juwon Hong, Taehoon Hong
In this study, a WebCYCLONE simulation was used to predict direct cost and noise exposure level more accurately for determining the optimal construction equipment allocation. Therefore, the accuracy of the proposed methodology was verified by measuring working hours to estimate the direct cost and noise level of an actual site and then comparing them with the values predicted by the WebCYCLONE simulation. The WebCYCLONE simulation was set to run over the 8 hours with 250 cycles, according to the site work hours. In particular, a measurement date was decided as the day when only the target construction process was selected for the case study in Section 3 to remove the noise from other construction activities. The working hours were calculated by measuring the start and end times of the construction process. The noise level was measured inside the construction site to minimize the effect of noise outside the site, and measurements were conducted using the approved equipment (NL-42 (RION 2016)) at a location 1.5 m away from the soundproofing walls according to the environmental noise measurement standards of MOE (refer to Figure 3) (Ministry of Environment 2006).
In-door laboratory high-speed testing of tire-pavement noise
Published in International Journal of Pavement Engineering, 2022
S. Han, B. Peng, L. Chu, T. F. Fwa
This paper has described a new in-door high-speed testing facility HTP2 for measurements of tire-pavement noise between a full-size tire and laboratory fabricated pavement slab specimens. The facility allows 12 specimens to be tested in a single test run up to a test speed of 70 km/h currently, and 100 km/h eventually. The On-Board Sound Intensity (OBSI) Method was adopted for the tire-pavement noise measurement. The reliability and repeatability of the test measurements were demonstrated. It was found that with a double-specimen layout, the measured sound intensity would be within 1.08 dBA of the mean value at 95% confidence level. The repeatability of the tire-pavement noise measurements was also demonstrated for the double-specimen layout. A test programme involving eight different pavement surface types demonstrated that the HTP2 test measurements were able to (i) measure sound intensity-frequency characteristics of tire-pavement noise matching those of actual vehicles and pavements, (ii) differentiate sound intensity of tire-pavement noise generated by different pavement surface types, (iii) identify increase in tire-pavement noise caused by texturing of concrete pavement surface, (iv) detect differences between tire-pavement noise generated by longitudinally and transversely tined concrete pavement surfaces, and (v) measure the effects of surface macrotexture on tire-pavement noise.
Analysis of occupational injuries and the risk management of automobile parts manufacturing work
Published in International Journal of Occupational Safety and Ergonomics, 2021
Seung Tae Yang, Byung Yong Jeong, Myoung Hwan Park
As regards the studies on the work environment, a 10-year mortality study of workers working at automobile engine and parts factories located in Erie county, New York, USA composed of casting, forging, machining and assembly of parts and engines was done [11]. Diseases related to neoplasm, the respiratory system and the circulatory system were found to be the major causes of death in the research. Workplace heat stress assessments were conducted in automotive and automotive parts manufacturing companies [12] under the protocols recommended by the National Institute for Occupational Safety and Health (NIOSH), USA. It was found that, in the sectors assessed, as many as 28% of workers were at risk of health impairment related to heat stress. On request from the United Auto Workers union, NIOSH conducted an assessment of physical hazards (heat stress/strain evaluation in the painting process, ergonomics evaluation and noise measurement in press jobs) at an automobile parts manufacturing facility [13]. Taking a rest period in the painting process was recommended. In press jobs, wearing hearing protectors properly and devising measures to reduce the amount of shoulder abduction and wrist flexion were the recommendations made. Analysis of occupational exposure of workers to heavy metals such as aluminum, cadmium, chromium and lead in automobile part manufacturing plants of metal welding and metal forming in Puebla, Mexico was performed [14]. Recommendations for strengthening safety policies were also proposed.