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Background and purpose: Noise pollution, as an unwanted and annoying sound that can negatively impact human health and well-being, has become one of the major environmental problems in the world. This type of pollution not only disrupts peace and comfort but can also have serious consequences for human physical and mental health. Despite the importance of the issue of exposure to harmful physical factors and their impact on health, few studies have been conducted on traffic noise based on the conditions in Iranian cities. Considering the importance of urban traffic noise, the lack of domestic studies on its characteristics and how it affects the cognitive and physiological performance of exposed individuals, and its importance and decisive role in the occurrence of errors and mental functions, this research aimed to investigate the physiological and mental performance in exposure to traffic noise pollution in Sari city. Materials and methods: This quasi-experimental intervention study was conducted in the summer of 1401 (2023) on 40 students of Mazandaran University of Medical Sciences. To minimize confounding factors, the inclusion criteria were as follows: age range of 20-30 years, normal hearing (hearing loss less than 25 dB), and no history of taking specific medications. All experiments were conducted in an acoustic chamber measuring 3 by 2 meters with a temperature of 23°C, humidity of 50%, and illuminance of 400 lux. Physiological parameters (heart rate, blood pressure, and core body temperature) were measured in acoustic comfort and traffic noise exposure conditions. Cognitive performance was assessed using the Continuous Performance Test (CPT) in exposure and non-exposure conditions. The structural correlation of this test was estimated by the researchers to be 0.89. Data analysis was performed using descriptive and analytical tests in SPSS v24. Results: According to the findings, 52% of the students studied were female. The mean age of the participants was 24.23 years with a standard deviation of 4.99 years, a minimum of 19 years, and a maximum of 38 years. 76.3% of the participants were single and 23.7% were married. Based on the exposure results, the average sound pressure level of traffic noise in the exposure group was reported as 75.45±0.11 dBA. It was observed that the heart rate and core temperature of the exposure group increased significantly (P

Background and purpose: Noise pollution, as an unwanted and annoying sound that can negatively impact human health and well-being, has become one of the major environmental problems in the world. This type of pollution not only disrupts peace and comfort but can also have serious consequences for human physical and mental health. Despite the importance of the issue of exposure to harmful physical factors and their impact on health, few studies have been conducted on traffic noise based on the conditions in Iranian cities. Considering the importance of urban traffic noise, the lack of domestic studies on its characteristics and how it affects the cognitive and physiological performance of exposed individuals, and its importance and decisive role in the occurrence of errors and mental functions, this research aimed to investigate the physiological and mental performance in exposure to traffic noise pollution in Sari city. Materials and methods: This quasi-experimental intervention study was conducted in the summer of 1401 (2023) on 40 students of Mazandaran University of Medical Sciences. To minimize confounding factors, the inclusion criteria were as follows: age range of 20-30 years, normal hearing (hearing loss less than 25 dB), and no history of taking specific medications. All experiments were conducted in an acoustic chamber measuring 3 by 2 meters with a temperature of 23°C, humidity of 50%, and illuminance of 400 lux. Physiological parameters (heart rate, blood pressure, and core body temperature) were measured in acoustic comfort and traffic noise exposure conditions. Cognitive performance was assessed using the Continuous Performance Test (CPT) in exposure and nonexposure conditions. The structural correlation of this test was estimated by the researchers to be 0.89. Data analysis was performed using descriptive and analytical tests in SPSS v24. Results: According to the findings, 52% of the students studied were female. The mean age of the participants was 24.23 years with a standard deviation of 4.99 years, a minimum of 19 years, and a maximum of 38 years. 76.3% of the participants were single and 23.7% were married. Based on the exposure results, the average sound pressure level of traffic noise in the exposure group was reported as 75.45±0.11 dBA. It was observed that the heart rate and core temperature of the exposure group increased significantly (P<0.05). The average error (omission and commission) between the control and exposure groups had a significant difference and the average of these variables was lower in the control group. Also, the reaction time in the exposed condition had a significant difference with the non-exposed condition (P<0.05). Conclusion: With the rapid growth of urbanization and the increasing density of traffic on roads and streets, noise pollution from traffic has become an unavoidable problem in modern societies, inevitably impacting human health and safety .because of the importance of traffic noise and the inevitable encounter with it, can be considered very important in terms of health aspects and occurrence of safety consequences. Therefore, paying attention to traffic noise exposure, human performance status, and influencing factors through investigations and research is necessary. [ABSTRACT FROM AUTHOR]

The development of technology and the advancement of science and technology in large and industrial cities have been associated with the destruction of the environment and various pollutions in human societies. One of the most obvious types of pollution is noise pollution, which causes mental and nervous diseases. In this article, with the aim of evaluating the noise pollution and the impact of social, physical and environmental variables in the urban environment, the evaluation of the sound landscape during the peak activity hours of District2 of Tabriz metropolis has been discussed. In terms of research method, this article is a combination of descriptive-analytical, documentary and survey methods. First, district2 was divided into squares of 200×200 meters based on the 1996 ISO standard grid method, and in the center of each square as a sound recording station with a decibel meter (Benetech digital sound meter model GM1357) the level of sound equivalent (Leq) with the sound pressure level of network A was measured with Fast response speed for 3 minutes, in two time periods: morning (8 to 11) and evening (19 to 22) in the months of Tir to Azar 1400 (July to December 2021). The maps of each dependent and independent variables were drawn in GIS software environment and evaluated using multiple linear regression model in SPSS software. The results of this research show that district2 has more noise pollution in the evening than in the morning. At the end, solutions to reduce noise pollution in the area are suggested. [ABSTRACT FROM AUTHOR]

Introduction: With the development of sciences and technologies, the growth and expansion of cities led to the destruction of the environment and production of various biological pollutions across human societies. Meanwhile, noise pollution has been one of the types of pollution that has adversely affected the comfort of urban residents and is found to be directly associated with the mental health of people in society. This type of pollution may cause mental diseases, irritability, allergy and other nervous and psychological diseases. This paper aimed to evaluate the noise landscape of District 4 of the metropolitan of Tabriz and investigate the amount of this type pollution in the peak hours of activities in this city, as well as the impacts of social, physical and environmental variables on the urban environment. Material and Methods: This article used a methodology that combined descriptive-analytical, documentary and survey methods. District 4 of Tabriz Metropolitan was divided into squares of 200*200 m in dimensions, based on a standard square grid (referred to in the ISO1996 Standards), with the center of each square designated as the noise acquisition station. The equivalent continuous sound level (Leq) of each station was measured for 3 minutes at twotime intervals of 8-11 a.m. and 7-10 p.m. in the months of June to December of 2021. Noises were acquired by using a decibel meter device (BENETECH Digital Sound Meter, GM1357 Model) at a sound pressure level of Grid A with a Fast Response Speed. Each of the maps pertaining to the independent and dependent variables of District 4 was separately sketched in GIS software, and then, the effects of each of the independent variables on dependent variables were examined by using a linear regression model in SPSS software. Results and Discussion: Surveys indicated that the noise landscape of District 4 of Tabriz Metropolitan consisted of children game noises, noises caused by vehicle and motorcycle traffic, trash trucks when loading trash bins and the sound of construction workers across the neighborhoods, noises caused by motorcycle horns and their swerving noise, the passage of trucks and vans, as well as motor vehicles, the traffic noise of inter-city buses and their horns, load trucks, international transit trucks on Pasdaran Highway and Santou Road, etc. Also, the review of 12 independent and 2 dependent variables indicated that population density, the distance from construction density and the distance from green spaces and garden uses, at two time intervals of morning and afternoon, were directly associated with the equivalent continuous sound level (Leq) and The distance from the pathway grid, the distance from treatment uses, the distance from industrial uses, the distance from the barren land and the distance from the aerial corridor of the metropolitan of Tabriz were found to be reversely related to the equivalent continuous sound level (Leq). Conclusion: Linear regression model results for evaluating independent and dependent variables (equivalent continuous sound level (Leq)) at each time intervals (morning and afternoon time intervals) indicated that the semi-eastern neighborhoods of District 4 suffer from higher noise pollution, while semi-western neighborhoods were dealing with lower amounts of nose pollution. In sum, District 4 experienced more noise pollution in the afternoon than in the morning. Eventually, the solutions suggested to eliminate and reduce the factors that cause noise pollution in District 4 of the metropolitan of Tabriz. [ABSTRACT FROM AUTHOR]

Background: Traffic noise is one of the most important causes of noise pollution and also one of the environmental problems in today's societies. According to the World Health Organization, traffic noise is the cause of physiological and psychological disorders. Psychological disorders include impaired mental function, disruption of daily activities, increased rates of traffic accidents, and decreased concentration. Physiological disorders include sleep disorders, hearing loss, hypertension, gastrointestinal disorders, and effects on job performance. Accordingly, the purpose of this study was to determine the relationship between mental performance of introverts and extroverts in the face of traffic noise. Methods: This study was performed on 40 students of Alborz University of Medical Sciences. The Mental Health Questionnaire were administered to all individuals. Also, traffic noise was recorded by a tape recorder for 15 minutes. Then, the participants were exposed to traffic noise in two modes of calm environment, and in both modes, a strope test was performed while playing the recorded sound. Finally, statistical analysis was performed to find the relationship between exposure to traffic noise and changes in mental function. Results: The results showed that after playing the sound in all participants, the mean consonant time decreased (p = 0.143), while the number of correct consonant responses increased after exposure to sound. (p=0.640) Conclussion: The results of this study showed that traffic noise does not have different effects on the mental function parameters, and there is no significant relationship between voice and age, as well as voice and gender.

Population growth as well as increasing migration to cities in recent decades has led to increased population density as well as the area of large cities. Noise pollution is one of the environmental problems in big cities, which endangers human health in various psychological and physical aspects. However, this type of pollution has received less attention than other pollutants. This research was conducted with the aim of investigating and modeling the effect of tree species on road noise pollution. The present study was carried out in Noor Forest Park in which 6 stations including 5 different tree stands and one control area were selected for the study. Measurement of noise pollution was performed in each station with 5 replications at distance intervals of 10, 20, 30, 40, 50, 60, 70, 80, 90, and 100 meters from the sound source with two noise frequencies of 250 and 500 Hz in two seasons of winter and summer. The studied characteristics include tree species, distance from the sound source, growing season (summer and winter), and stand attributes including mean diameter at breast height, the average height of the stand, basal area per hectare, total basal area of trees from the sound source to the location of receiver. Based on the model selection criteria, the linear model showed the best fit for modeling the effect of environmental factors on the amount of noise pollution. Based on the results, the effect of distance, species, season, intensity of noise pollution and total basal area of trees on the amount of noise pollution were significant. The distance from the source of noise pollution and the total basal area of the trees showed an inverse relationship with the amount of noise pollution. The highest noise pollution was related to the control areas without trees and the lowest was related to the Gleditsia-Alnus mixed stands. It can be concluded that noise pollution can be reduced more effectively with optimal design through afforestation of mixed stands so that the species cover different floors, especially at a height close to the ground. [ABSTRACT FROM AUTHOR]

The effects of emotions on all of man’s daily decisions are undeniable. Using, residing in, and leaving an urban space pertain to the users’ emotions. Therefore, it is important to measure and evaluate the users’ emotions in urban spaces. The purpose of this research is to identify the factors affecting emotions in urban spaces and prioritize them in the selected space. Theoretical Framework In the first step, the literature was reviewed, and a conceptual model for measuring emotional response was then presented. Based on this model, emotions can be measured in three layers: physiological, perceptual, and behavioral. The users’ affective response in the urban space can be investigated on that basis. This case study addresses a sequence of Emamat Street in the city of Mashhad, Iran. Methodology The research was conducted based on a hybrid method. A biometric sensor (Empatica-E4) was used to collect data at the physiological level. Cognitive data were collected through walking interviews and videos. In addition, the speed of walking in the behavioral layer was measured. The resulting data were analyzed quantitatively and qualitatively, and the factors affecting the emotional response in this street were finally identified. The factors identified as a result of the analysis made in the above three layers were adapted to each other. Based on the exploratory analysis made through the SPSS software, the factors affecting the emotional response were prioritized. Twenty people participated in this survey and shared their emotional responses in the selected sequence of Emamat Street, which is one kilometer long. Results and Discussion The results demonstrated that the users’ emotional response was pleasant. According to the results of the data in the biological layer, it was found that the part with a dominant natural character conveys more peace. Moreover, the monotonous sections, the inactive environments of the street, and the part with heavy traffic cause unpleasant emotional responses. The analysis of perceptual data indicated that the presence of greenery and retails exhibits a greater effect on pleasant feelings. The analysis of movement speed shows that in environments involving attractiveness, there is a diverse, relaxed decrease in the speed of movement over the space and the desire to stay. Based on the results, it was found that factors such as greenery, traffic, land use and activity, behavioral patterns, crowd, and noise pollution have effects on the emotional response. In order to prioritize the factors affecting the emotional response in the above space, the data were analyzed in the physiological and cognitive layers in SPSS. The results were rather the same. It can also be concluded that among the factors affecting the emotional response, non-physical ones, such as natural elements, crowd, noise pollution, and land use and activity, have greater influences than physical factors like the type of flooring and facade. Among these, the greatest effects on the desired emotional response are exhibited by the type of activity including exercise, the presence of a group of elderly people, and the existing nature, including tall trees on the edge of the park, visible vegetation, and plants and decorative flowers present over the space. Conclusion This study was designed to identify the factors influencing the affective and behavioral response in urban spaces. We first explained the conceptual framework of the research by reviewing the literature on studies conducted in this area and examining the theories related to the emotional response in urban spaces, factors affecting emotions within the city, and methods of measuring the affective and behavioral response in the city. The research methodology was developed along with a practical test for assessing the affective and behavioral response and the experiment path given the available tools and methods used in previous projects and studies. The results obtained from the analysis of the recorded data on the heart rates of the participants in the experiment, the speeds of their movement in each sequence, and their cognitive responses revealed that factors such as vegetation, vehicular traffic, land use and activity, behavioral patterns, crowdedness, and noise pollution are effective on the affective response, and, thereby, affect people’s senses. This research was conducted during the COVID-19 pandemic; thus, the constraints ruling over urban spaces made it more difficult to perform the experiment with more participants. Obviously, conducting the experiment with a larger number of participants can bring about more reliable results. The reason for using a homogeneous age and social group was to decrease the probability of recording data outside the standard range. Naturally, doing research with a larger sample size would allow use of more diverse age groups. Based on the above findings, some suggestions are made for designing the space based on emotions, as follows. - The vegetation and greenery space has a significant impact in the creation of a feeling of peace. The variety in the color and type of vegetation may also increase the pleasant feeling. However, if the vegetation reduces visibility, it would be effective in the creation of an unpleasant feeling. - Water in the urban space beings about a feeling of naturalness and tranquility in users. However, in a space filled with crowd and noise pollution, the sound of water can increase noise pollution. - The ground floor in urban spaces obviously affects the pedestrians’ perception more than other floors. Thus, the transparency of the wall, its beauty, variety, and coherence have prominent impacts in the creation of pleasant emotions. - It is better to avoid building long, rigid, inactive walls. If there are such spaces, the ground for creating activity at certain intervals should be provided. - The street-crossing areas should be designed in parts of the route with sufficient visibility for drivers and pedestrians; moreover, the pedestrian lanes need to be clear. - When there is a potential for overcrowding, the movement and activity interference should be minimized to reduce the resulting crowdedness and arousal. - The context for the emergence of desirable behavioral patterns such as exercise in the park should be provided in all directions, and a certain space for undesirable behaviors should be predicted as well. [ABSTRACT FROM AUTHOR]

This paper studies the flexible job shop scheduling problem with parallel machines by considering cleaner production criteria, dual human-machine resources, job release date, and machine speed-dependent processing time. The objective functions of this problem include minimizing the sum of earliness and tardiness and the speed increasing. Here it is assumed that the speed of the machines can be increased to reduce the completion time while the increasing the speed leads to increasing the noise pollution in the production environment, and due to the cleaner production approach which is a preventive approach, an attempt has been made to reduce the amount of noise pollution by minimizing the speed increasing. In this regard, first, a mixed integer-programming model was developed, and since the model is bi-objective and NP-hard, a NRGA is proposed and the obtained results are compared with the NSGAII considering some multi-objectives criteria. The results show that the proposed algorithm considering the MID criterion in instances with 10 and 25 jobs and considering the RAS criterion in instances with 25 and 100 jobs have better performance compare to the NSGAII. Furthermore, the TOPSIS method is also used for analysis and the results show the efficiency of the proposed algorithm.

The main purpose of this study is to study the relationship between urban morphology and noise pollution in the three regions of Tabriz (Imamiyeh and Manzaria neighborhoods). Data collection From the study area, audio data were collected in 45 shifts in the morning (7 to 10) and night (19 to 22) at 45 points in the study area. Audio data was collected using the Decibel X application. The results show that the average sound in the morning is 87.06 dB and the standard deviation is 10.16. Also, the average sound in the night interval is equal to 90.08 decibels and the standard deviation is 9.28. It is observed that the average of both mentioned intervals is higher than the standard. Based on the analysis of the average sound by the user, the terminal with the average sound of 95.52 decibels and the standard deviation of 2.94 had the highest average sound during the day. In the night interval, the terminal with the average sound of 95.81 decibels and the standard deviation of 3.43 has the highest average sound. Also, based on the standards presented in the section on theoretical foundations, it is observed that all applications are higher than the standard sound level. Wilcoxon test was also significant at the level of 0.000 which showed that the average sound in the study range for morning and night is higher than the standard 75 decibels.

Noise pollution, as one of the lesser-known environmental pollutants, has affected the residential areas of the country's metropolises. One of the main reasons for this problem is the lack of attention to spatial factors affecting noise pollution, lack of evaluation studies and insufficient familiarity with the methods of assessing the effects of development measures on noise pollution in the urban planning system. This study aims to spatial analysis and ranking of noise pollution in 15 regions of Isfahan metropolis. In this regard, the mixed research method (quantitative and qualitative) has been used and the required information has been collected through library and field methods. In addition, spatial analysis method in ArcGIS software was used for data analysis and Analytic Hierarchy Process (AHP) method in Expert Choice software was used to weight the indicators. The results indicate that the spatial distribution of noise pollution in the regions of Isfahan is unbalanced. As in the central regions 1, 3 and regions 8 & 10, mainly due to the existence of busy passages and non-observance of construction privacy for them, the impact of noisy land uses, population concentration and compactness, noise pollution is in a more unfavorable situation than other regions. Among the most important solutions to deal with this issue, can be mentioned to the observance of construction privacy for busy passages and noisy land uses in urban development plans, transfer of workshops and terminals from residential areas to non-sensitive areas and reducing congestion and increasing the complexity of designing new patches.

Background and purpose: Cognitive performance in workplace encompasses a wide range of work-related psychological activities. Meanwhile, personality traits as a mediating variable has a determining role in mental functions and occurrence of errors. The aim of this study was to investigate the effect of urban traffic noise pollution on working memory and sustained attention considering personality features in university students. Materials and methods: This interventional laboratory study was performed in 70 students. Urban traffic noise (Sari, north of Iran) was recorded and then the Cool Edit Pro software was used to check, edit the recorded noise, and prepare an audio clip. The students' cognitive performance were assessed using working memory (n-back task) and psychomotor consciousness task (PVT). Results: The mean ages of male and female students were 23.63±3.15 and 24.17±4.23, respectively. According to the Wilcoxon test, a significant relationship was seen between cognitive performances before and after exposure to urban traffic noise (P

This paper studies the flexible job shop scheduling problem with parallel machines by considering cleaner production criteria, dual human-machine resources, job release date, and machine speed-dependent processing time. The objective functions of this problem include minimizing the sum of earliness and tardiness and the speed increasing. Here it is assumed that the speed of the machines can be increased to reduce the completion time while the increasing the speed leads to increasing the noise pollution in the production environment, and due to the cleaner production approach which is a preventive approach, an attempt has been made to reduce the amount of noise pollution by minimizing the speed increasing. In this regard, first, a mixed integer-programming model was developed, and since the model is bi-objective and NP-hard, a NRGA is proposed and the obtained results are compared with the NSGAII considering some multi-objectives criteria. The results show that the proposed algorithm considering the MID criterion in instances with 10 and 25 jobs and considering the RAS criterion in instances with 25 and 100 jobs have better performance compare to the NSGAII. Furthermore, the TOPSIS method is also used for analysis and the results show the efficiency of the proposed algorithm. [ABSTRACT FROM AUTHOR]

IntroductionThe most important adverse effects of noise on humans have reduced work efficiency and physiological damaging effects such as increased heart rate, high blood pressure, permanent and temporary hearing loss, impaired vision, disrupting the body's balance system, causing nervous disorders and even nervous disorders. Much of the occupational disturbance is due to acoustic vibrations in agricultural mechanization, which is affecting a large number of farmers. In this regard, most of the noise and vibration come from two-stroke or four-stroke engines that are used in lawn mowers, sprayers, pits and more. These high-vibration equipment causes a great deal of damage to their operators. Portable lawn mowers are popular for working in urban and rural areas due to their low cost, low maintenance cost, high maneuverability and affordability. Therefore, the possibility of optimizing the muffler of a small combustion engine for a lawn mower was investigated and studied in the present stud.Materials and MethodsTo optimize the existing muffler, geometry of the factory muffler was first redesigned in solidworks 2014 software. Then the optimized muffler, along with the factory muffler exported into ANSYS CFX software and simulated in terms of velocity and pressure distributions. To evaluate the built muffler and compare its performance with the factory standard muffler, the mufflers were then mounted on a DOMA’s lawnmower model WPGD501 with a 42 cm3 engine volume and tested outdoors in a radius of 5 m. All sound recording tests were performed in steady state at a distance of 1m with a 45° angle and position along the exhaust outlet to reconstruct the user's ear position. A digital thermometer TEM-8820 and a PSA-V01 digital barometer were used to measure the sound pressure and an environment temperature.Results and DiscussionThe results showed that at 3000 rpm, the sound pressure level of the modified muffler decreased by 6.4% compared to the modified muffler. The same decrease in sound pressure level was achieved at 5000 rpm, equal to 4.5%. The results of this study showed that with increasing engine speed, pressure changes in the muffler had an upward trend. These changes in the modified muffler increased by 0.02 kPa at 3000 rpm and by 0.07 kPa at 5000 rpm. According to the outputs of the FFT diagrams, the intensity and amplitude of the output frequencies from the modified muffler significantly decreased almost at most frequencies. Therefore, effective pressure difference (ΔPrms) was used for the further investigations. The results of this study showed that the pressure changes in the muffler had an upward trend with increasing the engine speed. These changes in the modified muffler increased by 0.02 kPa at 3000 rpm and by 0.07 kPa at 5000 rpm.ConclusionsAccording to the results of the present study, by optimizing the internal muffler geometry of the lawn-mowers by installing internal blades and neutralizing the sound intensity inside the muffler, it is possible to reduce the sound pressure level by 4% to about 7% over the original muffler. It is a very simple and inexpensive method for the manufacturers of such engines.

Background and Objective: Due to major constraints on time, implementation, and funding in every industry, one of the essential strategies for the management of noise control and selection of the best method is to prioritize noise control methods. The present study aimed to prioritize noise control methods in a battery factory using the Analytical Hierarchy Process (AHP). Materials and Methods: The present study was conducted based on a descriptive-analytical cross-sectional design. After measurement of sound pressure level and identification of the main sources of noise pollution, Content Validity Index (CVI) and Content Validity Ratio (CVR) were used for screening the criteria and methods of noise control. The relative weight of each of them was calculated by two factors of Eigenvalue and Eigenvector to prioritize noise control methods based on the study criteria. Results: Based on the results, the Inconsistency Ratio (IR) in pairwise comparisons in all cases was less than 10%, and the consistency of the answers was confirmed. Moreover, among the study criteria, the acoustic efficiency of method with weight (0.1810), and among the proposed methods for noise control, the method of controlling the time of exposure to noise and training of workers with weight (0.1732) had the highest priority. Conclusion: As evidenced by the obtained results, the best criterion for selecting a sound control device is the acoustic efficiency of the method. Furthermore, based on the results, controlling the duration of exposure to noise and training workers in conditions of high noise exposure was the best method to control noise in a battery factory.

Background & Aims: Although sound waves are considered as an essential factor in human life, but in some cases and in special circumstances, hearing these sound waves is not very pleasant and exposure to annoying sounds too much will cause hearing loss in humans. (1). Noise pollution is defined as the emission of any kind of noise and excessive vibration in open spaces and is one of the examples of damage to the environment (2); So that it will have very clear effects on human health and ecosystems (3). In addition to the negative impact on the auditory system, noise as a stressful source will also affect the human heart and arteries and stimulate the nervous system, cause anxiety and increase mental health problems (7). Environmental conditions have a significant impact on how sound is emitted. However, after a period of exposure to noise, man becomes accustomed to those conditions; But again, noise pollution is a cause of fatigue and reduces the capacity of human work, both in mental jobs and in simple physical jobs. On the other hand, noise pollution affects the mental state of people and causes problems in adapting to their work environment and even the community and family; the result will be a reduction in productivity and productivity (10). Gyms and swimming pools are poorly sounded environments due to the lack of sound-absorbing materials, noisy sports activities, the simultaneous presence of many users, and the heavy use of whistles for communication. As a result, physical education educators not only suffer from prolonged stress and strain, but are also exposed to noise-induced hearing loss. Therefore, it is necessary to carefully analyze all the factors that can affect the noise in these environments, in order to provide guidelines for officials and planners for stress management and hearing protection programs (11). The present research is an applied research that has been done by networking method. The purpose of this study was to measure noise pollution in indoor pools with emphasis on the health of staff and users of indoor pools in Mashhad. Methods: The sound level was measured as an equivalent level by the portable device and software Decibel X version 2020 and was compared with the sound standard (OSHA-90 dBA). Measurements Calculated the parameters of sound pressure level (SPL), average sound level (LP) ̅), continuous sound equivalent level (Leq) and individual daily dose of LAEp, d in 3 shifts. Results: The lowest sound pressure level in the first turn was 76.5 dB and the highest pressure level in the second turn was 97.7 dB. The average sound pressure level increases with the change of time from morning (11 am) tonight (8 pm). The average sound level in indoor pools is equal to 78.4 dB and the level is equal to 85.42 and the individual daily dose of LEp, d personnel and users is 92.45 and 87.15 dB, respectively. The permissible noise exposure time was estimated at 1 hour and 30 minutes for users and 5 hours for personnel, indicating that users were 30 minutes and personnel 3 hours more exposed to noise pollution than allowed. Conclusion: In the indoor pools of Mashhad, staff and users are exposed to high noise pollution and the possibility of physical and psychological injuries is high. Existing sound levels are higher than international and national standards and indicate that the use of engineering management principles is necessary to reduce the sound level in indoor pools. Swimming is one of the most popular sports activities. Diving in water, the whistling of coaches and saviors, moving equipment, the sound of music playing, athletes talking, emotional screams, etc. all provide the ground for raising the sound level. Accordingly, the prolonged or frequent presence of an athlete in an environment with high noise levels, can increase the risk of injuries due to noise pollution and may even reduce his efficiency. The results of the present study showed that the sound level in the shifts in which men were present was not much different from the shifts of women. Also, in the morning sports times (11/15/11), the sound level was significantly lower than in the evening (17-17-17), which is probably due to the smaller number of athletes in the morning compared to the evening. In general, the absence of the above conditions has caused an increase in the sound level in the selected indoor pools. Of course, there was no significant difference in terms of sound level in different areas of Mashhad and in this regard, there can be no difference in terms of sound level published in indoor pools based on zoning in Mashhad. This research is methodologically consistent with the research conducted by Taheri et al. (1398) (32). But; their results cannot be generalized and compared with each other, because the environment studied in this study was closed space. However, the results are to a large extent consistent with the results of studies of Bahmanpour et al. (2011), Mafi et al. (2009) (28, 11). Comparison of the average sound level in the indoor pools studied with international standards shows that most of the measured pools (except pools 9 and 10) have a lower average sound level than the NIOSH, OSHA and ACGIH standards. However, all the pools studied have a sound level higher than the standard of the Environmental Protection Agency, as well as the standard of leisure centers and parks in the United Kingdom (which is equal to 55 decibels). They also differ from the United Nations Development Program (UNDP) standard of 55-65 decibels. On the other hand, the allowable exposure to the sound level in the studied pools for athletes is 1 hour and 30 minutes, which is basically 30 minutes less than the current time. In other words, at present, athletes are exposed to sound levels for about 30 minutes longer than allowed. Also, for employees (management and employees) the allowable limit of 5 hours was set, which is basically 3 hours less than the current situation. Therefore, due to the sound level in swimming pools, personnel should be present in the pool environment for 3 hours less so as not to be exposed to high sound levels. [ABSTRACT FROM AUTHOR]

Background and purpose: Cognitive performance in workplace encompasses a wide range of work-related psychological activities. Meanwhile, personality traits as a mediating variable has a determining role in mental functions and occurrence of errors. The aim of this study was to investigate the effect of urban traffic noise pollution on working memory and sustained attention considering personality features in university students. Materials and methods: This interventional laboratory study was performed in 70 students. Urban traffic noise (Sari, north of Iran) was recorded and then the Cool Edit Pro software was used to check, edit the recorded noise, and prepare an audio clip. The students' cognitive performance were assessed using working memory (n-back task) and psychomotor consciousness task (PVT). Results: The mean ages of male and female students were 23.63±3.15 and 24.17±4.23, respectively. According to the Wilcoxon test, a significant relationship was seen between cognitive performances before and after exposure to urban traffic noise (P<0.05). In fact, after exposure to traffic noise, the mean reaction time, response time, and the number of incorrect answers in cognitive tests increased by 8.54%, 9.11%, and 60.61%, respectively. Also, there was an inverse significant correlation between neuroticism and reaction time and accuracy (percentage of correct answers) in students' cognitive performance associated with working memory and sustained attention (P<0.05). Conclusion: Current study can be effective in improving cognitive performance, adopting management strategies in selection of individuals, and establishing a balance between traffic noise and cognitive features in the workplace. [ABSTRACT FROM AUTHOR]

Introduction and purpose: Noise is one of the most harmful physical issues in a workplace that can cause stress. Transit bus drivers are exposed to environmental and bus noises that can act as stressors for them. In this regard, the present study aimed to determine the effect of noise exposure on occupational stress of bus drivers in Bojnourd, Iran in 2018. Methods: This cross-sectional descriptive study was performed on 110 bus drivers in Bojnourd. The Philip L. Rice Questionnaire (1992) was used to assess their occupational stress, and SV 971 Sound Level Meter (SVANTEK-971) was used to measure noise exposure. Finally, the collected data were analyzed in SPSS software (version 20) using descriptive statistics (mean and standard deviation) and correlation statistical tests. Results: Based on the findings, the level of occupational stress was high, moderate, and low in 102 (92.7%), 4, and 4 cases, respectively. The results of the noise measurement revealed that the level of noise exposure was standard for all the subjects. The mean value of the equivalent continuous sound pressure level (LAeq) was 75.43±2.74 dB. There was no significant relationship between LAeq and the level of stress experienced by the drivers. However, there was a significant relationship between LAeq and the occupational interest subtest (P

Population growth and the increase in urban migration in the past decades have led to an increase in population density and size of major cities. Unfortunately, this kind of pollution has mostly gone under-noticed. The purpose of this research was to model the correlation between noise pollution level and landscape metrics of urban structures and vegetation. To do so, 67 stations were selected in different parts of Isfahan and noise parameters were measured at peak traffic hours (16 to 19) during the fall season. Sampling stations were located through a systematic-random method based on the amount of construction, green spaces and structural diversity. There were 27 types of landscapes and three stations were randomly selected in each. In most stations, the noise level was above the permitted level(Residential 45-55, Residential-Commercial 50-60). The advanced regression method of random forest was used for the analysis. Through this method, the most effective metrics identified in different buffers were IJI index, FRAC_MN index, CLUMPY index, CONTIG_MN index, SHAPE_MN index, ENN_MN index. Also, checking of the first six metrics in each of the buffers and land uses showed the importance of the metrics is different. Identification of important metrics in each buffer and land use helps better design urban blocks and their arrangement.

Background and Objective: Conversion of houses into residential towers in worn-out urban textures increases population. Schools of the vicinity would face with multiplicity and limited space for students, leading to noise pollution. The purpose of this study was to evaluate the noise levels during morning and afternoon shifts among two primary schools in Zanjan. Materials and Methods: Measurements had been done using sound level meter, KIMO DB100. The equivalent noise level (Leq) measured during school year (2018-2019) in 10 stations. The measurements were done in three seasons (autumn, winter and spring) and in each season for two weeks. The data of the two schools were used for drawing charts and zoning by ArcGIS using IDW method. In addition, questionnaires were distributed among the teachers and school’ neighbors. The data were analyzed by SPSS software. Results: The results showed that all the stations were tackled with noise pollution. The highest levels were related to school’s shift change and break times. The morning shift schools experienced higher levels of noise in comparison to the afternoon ones (1.87 and 2.1 dB, respectively for boys and girls). Leq values for boys’ school was 2 dB higher than that of the girls’. The noise level in the schools were 72 dB, which is 17 dB higher than the standard level 55 dB. Conclusion: The residents living close to the schools were exposed to noise pollution for almost 10 hours a day. This could be regarded as harmful. The zoning maps showed that southwest side of the yard, adjacent to the neighboring residential buildings, had the highest levels of noise. This study demonstrated the site selection for the schools were not properly done. Having a control strategy is needed.

Introduction The most important adverse effects of noise on humans have reduced work efficiency and physiological damaging effects such as increased heart rate, high blood pressure, permanent and temporary hearing loss, impaired vision, disrupting the body's balance system, causing nervous disorders and even nervous disorders. Much of the occupational disturbance is due to acoustic vibrations in agricultural mechanization, which is affecting a large number of farmers. In this regard, most of the noise and vibration come from two-stroke or four-stoke engines that are used in lawn mowers, sprayers, pits and more. These high-vibration equipment causes a great deal of damage to their operators. Portable lawn mowers are popular for working in urban and rural areas due to their low cost, low maintenance cost, high maneuverability and affordability. Therefore, the possibility of optimizing the muffler of a small combustion engine for a lawn mower was investigated and studied in the present stud. Materials and Methods To optimize the existing muffler, geometry of the factory muffler was first redesigned in solidworks 2014 software. Then the optimized muffler, along with the factory muffler exported into ANSYS CFX software and simulated in terms of velocity and pressure distributions. To evaluate the built muffler and compare its performance with the factory standard muffler, the mufflers were then mounted on a DOMA's lawnmower model WPGD501 with a 42 Cm engine volume and tested outdoors in a radius of 5 m. All sound recording tests were performed in steady state at a distance of lm with a 45٥ angle and position along the exhaust outlet to reconstruct the user's ear position. A digital thermometer TEM-8820 and a PSA-vol digital barometer were used to measure the sound pressure and an environment temperature. Results and Discussion The results showed that at 3000 rpm, the sound pressure level of the modified muffler decreased by 6.4٥/o compared to the modified muffler. The same decrease in sound pressure level was achieved at 5000 rpm, equal to 4.5٥/٠. The results of this study showed that with increasing engine speed, pressure changes in the muffler had an upward trend. These changes in the modified muffler increased by 0.02 kPa at 3000 rpm and by 0.07 kPa at 5000 rpm. According to the outputs of the FFT diagrams, the intensity and amplitude of the output frequencies from the modified muffler significantly decreased almost at most frequencies. Therefore, effective pressure difference (APrms) was used for the further investigations. The results of this study showed that the pressure changes in the muffler had an upward trend with increasing the engine speed. These changes in the modified muffler increased by 0.02 kPa at 3000 rpm and by 0.07 kPa at 5000 rpm. Conclusions According to the results of the present study, by optimizing the internal muffler geometry of the lawn-mowers by installing internal blades and neutralizing the sound intensity inside the muffler, it is possible to reduce the sound pressure level by 4% to about 7% over the original muffler. It is a very simple and inexpensive method for the manufacturer of such engines. [ABSTRACT FROM AUTHOR]

Introduction and purpose: Noise pollution can exert negative effects on mental health. In this regard, the present study aimed to evaluate the noise levels in sugar factory of Debal Khozaei agro-industry complex in 2018. Methods: For the current study, sound and audio parameters were measured using a sound meter. These audio parameters included sound pressure level and minimum and maximum values measured in 9 units located in the interior space of the factory entailing 38 study stations with 30 points in open space. It is worthy to note that sound measurements were performed twice a week in morning and afternoon shifts at time intervals of 15 min. Data were analyzed in SPSS software (version 16) using the ANOVA test. Results: Based on the results, the maximum and minimum sound pressure levels of power plants and white sugar warehouse were 0.86 ± 91.10 and 0.44 ± 91.10 dB, respectively. Additionally, the comparison of the average sound pressure level at different stations in the power plant and raw sugar production units, as well as some stations in the sugar refinery, lime kiln, and boiler exceeded the standard limit of 85 dB. However, this value was found to be below standard in the open space of the factory. Conclusion: The ongoing monitoring along with the application of noise reduction techniques is recommended due to the excessive noise levels in some parts of the factory.

Background and Objective: Noise pollution causes many physiological, psychological, economic and social effects on human life. This issue is more important in the environment of industrial workplaces. This research aimed to adopt the functions of GIS for evaluating and spatial analysis of noises in industrial environments. Materials and Methods: At the initial step, the spatial data for industrial halls were collected and stored as map layers into GIS database. Then, the noise pollution data sampled. The data, including the locations and values of sound pressure levels, were used for the relevant spatial analyses. Results: The analyses included: the estimation of sound pressure levels in different areas of halls and at the given distance from machines, determination of noisy areas, development of sound noise risk map, interpolation of sound pressure level data, prioritization of the sound sources (i.e., machines) for a given point, prediction of sound pressure levels by moving machines, and optimal site selection and distribution of machines. The mean of noise pressure level was 95 dB for knitting hall, 93 dB for spinning hall 1 and 88 dB for spinning hall 2. Conclusion: GIS plays a key role in the assessment of noise pollution in industrial workplaces. It is an appropriate tool to store, analyze, manage, and present all types of sound pressure spatial data. Specifically, the use of such system provides spatial intelligence and could help monitor, detect, control, and solve real word sound noise pollution issues.

Background and Objective: Due to major constraints on time, implementation, and funding in every industry, one of the essential strategies for the management of noise control and selection of the best method is to prioritize noise control methods. The present study aimed to prioritize noise control methods in a battery factory using the Analytical Hierarchy Process (AHP). Materials and Methods: The present study was conducted based on a descriptive-analytical cross-sectional design. After measurement of sound pressure level and identification of the main sources of noise pollution, Content Validity Index (CVI) and Content Validity Ratio (CVR) were used for screening the criteria and methods of noise control. The relative weight of each of them was calculated by two factors of Eigenvalue and Eigenvector to prioritize noise control methods based on the study criteria. Results: Based on the results, the Inconsistency Ratio (IR) in pairwise comparisons in all cases was less than 10%, and the consistency of the answers was confirmed. Moreover, among the study criteria, the acoustic efficiency of method with weight (0.1810), and among the proposed methods for noise control, the method of controlling the time of exposure to noise and training of workers with weight (0.1732) had the highest priority. Conclusion: As evidenced by the obtained results, the best criterion for selecting a sound control device is the acoustic efficiency of the method. Furthermore, based on the results, controlling the duration of exposure to noise and training workers in conditions of high noise exposure was the best method to control noise in a battery factory. [ABSTRACT FROM AUTHOR]

Introduction and purpose: Noise pollution is an important health problem in most industries, especially in the small inland industries. The purpose of this study was to evaluate the noise pollution in turning and polishing shops in Qom, Iran, and compare it with the sound standards in the country. Methods: In the present descriptive cross-sectional study, noise assessment was performed using the local measurements to evaluate occupational exposure with a dosimeter (CEL 320, Casella CEL, Inc., New York) in 20 turning shops and 20 polishing shops. Then, the equivalent sound balance was calculated for a work shift and compared with the sound standards In Iran. Results: The results showed that the average equivalent sound levels in turning and polishing shops were 93.1 and 100.4 dB, which were unauthorized in comparison with the national sound standards. Furthermore, the noise pollution outside the shops was reported beyond the standards of the relevant region. It should be noted that regarding the evaluation of hearing sensitivity, 86.1% of the workers did not have a hearing test. In addition, sanitary inspections were not carried out in 83% of the shops. However, 64% of the shops were not upgraded and the participation rate of the shop owners was 53% in the improvement measures.Conclusion: According to noise pollution in turning and polishing shops and the effects on workers and the public, noise control methods are proposed, such as the provision of personal protective equipment, reduction of labor time, correct choice of machines, and installation of noise-reduction tools. With respect to noise pollution, the correct locating of shops and organizing noisy industries were proposed.

Traffic noise pollution is a serious threat to wildlife species, resulting in isolating and reducing the population. The Asian Highway of Tehran-Mashhad, from which a 26.51 km long part is located inside Golestan National Park, is the main source of noise disturbance inside the area. The purpose of this study was to determine the most important criteria for noise pollution of this road; in order to achieve this goal, the Principle Components Analysis method was used. To assess the sound emissions and to study the parameters affecting it, desk studies and field visits were used in a 250-meter buffer zone. A total of 16 variables in three different categories of traffic parameters, geometry parameters and environmental parameters were extracted, andthe circular plots were measured at a radius of 25 m for 15 minutes. The results of PCA showed that six main factors including the speed of light vehicles, the humidity, the altitude above sea level, the number of light vehicles, the distance from the road and the plot slope could justify a total of 72.396 % of the variance of the data. Based on the results, management measures could be taken to reduce the noise pollution based on the extracted criteria, and the noise pollution could be managed more efficiently by spending less time and money.

Abstract Background and aims: Using water pump in residential buildings to provide the required water pressure is accompanied by noise pollution and the annoyance of residents. So, the purpose of this study is to reduce water pump noise pollution with designed acoustic curtains in a residential building of Qazvin city. Methods: The mean sound pressure level was measured before and after control intervention around the sound source based on ISO 9612, using the sound level meter (Casella-Cell.450). The sound level meter was calibrated using a calibrator (Cell-110/2). The frequency analysis was done in 1.1 octave band and the weighting frequency of A. Acoustical features of acoustic curtains (thickness, material and dimensions)were determined on the base of required sound transmission loss in predominant frequency. The volumetric flow of air required to decrease the temperature inside the enclosure up to 40°C to maintain a reasonable air temperature for pump performance was calculated using the energy-mass conservation law. Temperature inside the enclosure was measured with a mercuric thermometer. Results: The mean sound pressure level before and after control around the pump was measured 67 dBA and 46 dBA respectively. The required insertion loss in predominant frequency(2000 Hz) to accommodate noise limit in residential buildings was considered to be 26 dB and based on which acoustic curtain surface density was calculated between. The average sound pressure level measured after control (46dBA) with predicted sound pressure level by mathematical calculation after control (47dBA) was not significantly different. The volumetric flow rate required to maintain a temperature of 40°C inside the enclosure was calculated to be 1.2 cubic meters per minute. The temperature was measured inside the enclosure of 38°C. Conclusion: Control of noise pollution using acoustic curtains with a lower cost and weight, higher installation speed and higher sealing can be considered as one of the proper methods for enclosing noise resources. Keywords: Noise pollution, Water pump, Acoustic curtains, Noise control.

Soundscape analysis, using acoustic indices, provides researchers with valuable ecological information to assess biodiversity, species behavior, and noise pollution. In this study, to analyze biophonies and anthrophony in six urban parks in Isfahan city in spring, six acoustic indices, including Acoustic complexity index (ACI), Acoustic Diversity Index (ADI), Acoustic Evenness Index (AEI), and Bioacoustic Index (BI), Normalized Difference Soundscape Index (NDSI) and Entropy Index (H) were used and quantified using Seewave Package in R software. In the next step, using ANOVA test, we evaluated the significance of difference between values of the indices among the six parks. We also calculated the degree of correlation between pairs of the indices among and within the parks using Tukey test. According to the results of ANOVA and Tukey tests, the highest values of BI, NDSI, ACI, ADI, AEI and H indices were obtained for Sofeh Park with values of 51.63, 0.99, 2267, 1.46, 0.89 and 0.82, respectively and the lowest values of the these indices were also calculated for Mahmoud-Abad (16.56 and - 0.49), Isargaran (1787) and Bagh-Ghadir (0.05, 0.67 and 0.41) Parks. Among the indices, the most significant difference was calculated for the two indices of ADI and NDSI and between the Sofeh and Mahmoud-Abad Parks, indicating the effect of factors such as edge effect and birds diversity on these indices. Based on the results, it can be concluded that NDSI and BI indices are suitable tools for evaluating ecosystem quality and can be used in green space management and urban biodiversity assessment. [ABSTRACT FROM AUTHOR]

Background and Objective: Conversion of houses into residential towers in worn-out urban textures increases population. Schools of the vicinity would face with multiplicity and limited space for s tudents, leading to noise pollution. The purpose of this s tudy was to evaluate the noise levels during morning and afternoon shifts among two primary schools in Zanjan. Materials and Methods: Measurements had been done using sound level meter, KIMO DB100. The equivalent noise level (Leq) measured during school year (2018-2019) in 10 s tations. The measurements were done in three seasons (autumn, winter and spring) and in each season for two weeks. The data of the two schools were used for drawing charts and zoning by ArcGIS using IDW method. In addition, ques tionnaires were dis tributed among the teachers and school’ neighbors. The data were analyzed by SPSS software. Results: The results showed that all the s tations were tackled with noise pollution. The highes t levels were related to school’s shift change and break times. The morning shift schools experienced higher levels of noise in comparison to the afternoon ones (1.87 and 2.1 dB, respectively for boys and girls). Leq values for boys’ school was 2 dB higher than that of the girls’. The noise level in the schools were 72 dB, which is 17 dB higher than the s tandard level 55 dB. Conclusion: The residents living close to the schools were exposed to noise pollution for almos t 10 hours a day. This could be regarded as harmful. The zoning maps showed that southwes t side of the yard, adjacent to the neighboring residential buildings, had the highes t levels of noise. This s tudy demons trated the site selection for the schools were not properly done. Having a control s trategy is needed. [ABSTRACT FROM AUTHOR]

Introduction: Noise is one of the most important pollutants in worksites. Hospitals are imposed to noise pollution. Considering lack of research in Sari educational hospitals and applicability of noise control by engineering controls and education, we proposed this research to evaluate the sound pressure level (SPL) in three educational hospitals of Sari, Iran. Methods: In a descriptive-analytical study, the SPL of three hospitals was evaluated using sound level meter (model; CACELLA CELL-490, made in England). The evaluation was performed in 1.5 meter height, in three shifts, and in three days of the week. Data were analyzed using descriptive statistic methods and SPSS software version 24. For assessing the rate of effective factors, the GEE (Generalized estimating Equation) methods were used. Results: According to the results, the mean SPL was 63.30 ± 7.33 dB and a significant difference was observed between the mean SPL and the standard (35 dB) (p <0.001). Moreover, the highest mean of sound in hospitals was observed in Fatemeh Al-Zahra Hospital. Considering the week days, Saturday and among shifts, the night shift had the highest mean SPL. Conclusion: The findings showed that SPL was higher than the Iranian National Construction Regulations and World Health Organization (WHO) standards in all evaluated places. So, the noise control programs should be considered seriously. [ABSTRACT FROM AUTHOR]

Introduction: One of the main causes of urban noise pollution is traffic noise, which causes a variety of physical and mental effects, sleep disorders, hearing loss, and quality of life. The purpose of this study was to assess the noise pollution caused by traffic and its effects on sleep disorders and the people’s quality of life in Shiraz city. Methods: This descriptive and analytic study conducted on 280 residents in heavy traffic and low-traffic areas of the city that selected according to the sampling method. Data collection included: quality of life questionnaire (WHOQOL: BREF), Herzberg sleep disorders questionnaire (PSQI) and by the CEL-440 sound level meter. Data analysis was performed using T-test, Chi - square and Pearsonchr('39')s correlation coefficient. Results: There was a statistical significant difference between traffic noise levels and sleep disorders in people nearby the low traffic boulevards (P

Background and Objective: Municipal waste transfer stations (WTS), operate as middle elements in waste collection and transfer to the final disposal site. Besides their benefits in waste transportation cost reduction, WTS can cause negative environmental impacts such as noise, air, and water pollution. Environmental impact assessment is an effective solution to reduce the environmental impacts of WTS. This research was conducted at evaluating the environmental impacts of various options defined for WTS in Tehran using the Rapid Impact AssessmentMatrix (RIAM) analysis method. Materials and Methods: This descriptive-analytical study was performed to assess the environmental impacts of WTS based on field observation and data collection. Comparing was included four options including: continue the current condition of the WTS, three other alternatives considered to be three other alternatives (WTS in open space with the construction of green space) and transfer in enclosed space and with construction of green space and without it. Finally, using the sustainability model, the stability of the options was also measured. Results: Based on the obtained results, the fourth option (indoor loading/ unloading along with establishment of green spaces in WTS) as the first priority for the Construction of transfer stations among the other options has the highest score (0.079) in terms of sustainability as well as the adverse environmental impacts. However, the current environmental status of Tehran WTS (first option) has the lowest score (-0.213) in terms of sustainability and the most destructive environmental impacts and found to be the last priority in establishment of transfer stations. Conclusion: Combined use of the RIAM and sustainability model can be a promising and reliable way to evaluate and improve the performance of (WTS). [ABSTRACT FROM AUTHOR]

Background and Objectives: Paying attention to the comfort of the patient during hospitalization is very important. Noise pollution can exacerbate a person's illness. Additionally, if the noise pollution exceeds the threshold limit, it will have negative effects on the staff and appropriate services. The aim of this study was to identify the sources and the level of noise pollution in the emergency and emergency care units and outside areas of educational hospitals at the 1st district of Tehran, in the winter of 2017. Materials and Methods: In this descriptive study, measurement of noise pressure level in emergency department, emergency care units and outdoors in four hospitals in working days and holidays was carried out at three times in the morning, noon and evening by the TES-1358 sound analyzer device. Data was analyzed using one-way ANOVA. Results: According to the results, the average and standard deviation of noise level in different sections of the hospitals on Saturday and Friday were respectively 62.79±7.32 and 57.98±6.43 dB during the morning shift, 66.15±8.09 and 65.16±7.82 dB during afternoon shift, 64.26±6.69 and 63.19±5.42 dB during the evening shift. There was no significant difference between the sound pressure levels on Friday and Saturday, among the rounds of measurements (morning, afternoon and evening) and among sections (the emergency department and the emergency care unit)(p>0.05). Conclusion: The results of the study showed that the rate of noise pollution in some parts of educational hospitals is higher than national and international standards. The necessary actions are recommended to be taken in order to decrease the noise and its causative factors for creating a more quiet environment for patients. [ABSTRACT FROM AUTHOR]

Background and Objective: The aim of noise control in a community is to improve its management in the community, because the traffic noise can affect neighboring residential areas. Well-planned noise management can eliminate this major and harmful component issue, which is one of the stresses of urban life on human health. However, before planning to decrease urban noise, it is necessary to determine the very noisy areas in a given city. Therefore, the objective of this study was to measure the main noise indices at the noisy areas of Zanjan City, Iran. Materials and Methods: This study was performed in the central area of Zanjan City, with heavy traffic. For this purpose, the equivalent sound level (Leq), the day-night sound level (Ldn), the day-evening-night sound level (Lden), the noise pollution level (NP) and the traffic noise index (TNI) were measured in 19 stations in the first half (winter and spring) of 2012. The measurements were conducted in the main streets of this area as recommended by EPA guidelines and finally the results obtained were mapped using the ArcGIS (Ver. 10.2) software. Results: the noise maps in GIS showed clearly the variations of Leq, Ldn, and Lden indices in the study field area. Moreover, it was found that the hourly variations of Leq, Ldn and Lden in stations are completely function of population movements and therefore traffic loads in the Zanjan city center. In addition, the extent of violation of traffic noise level from the ambient noise standard was estimated by Lden at 100% stations (greater than 55 dB). The TNI values at 67 and 100% stations were more than 74 dB (A), but in the evenings the TNI values at 100% of stations were more than 74 dB (A). The NP values at 78% sampling stations were more than 80 dB implying traffic noise was annoying in the most stations and times. Conclusion: Using noise maps, NP and TNI indices can help intelligent traffic control planning, because the noise maps can be used to represent the movement of people in different times and parts of a city.

Introduction: noise pollution has a negative effect on physiological parameters, efficiency and auditory system. The aim of this study was to evaluate the performance of a sound screening method for estimating sound risk in small workshops of Hamadan city. Methods: This cross-sectional study was conducted in 22 plants with more than 20 workers. Noise screening was done using a screening form. Next, noise level was measured at all the plants by SL 4001 sound level meter and regular grid method. Data were analyzed using Pearson’s test and linear regression by SPSS version 16 software. Results: The mean (SD) scores of sound pressure level and screening form were 80.12 dB (7.277) and 60.50 (8.964) in the 22 understudy plants, respectively. The average measured workshop area and volume were 1448 and 10300, respectively. Pearson’s test revealed a significant relationship between the results of the two methods, (P > 0.046). Also the percentage of workers at risk (greater than 85 dB) was 32.29 and the percentage of workers within safe limit (less than 85 dB) was 63.3. While the largest percentage of workers in the caution zone (82 dB) was 67.04. conclusions: A correlation was shown between the results of the two methods. The use of this method to identify workshops with the possibility of noise pollution is effective.

Introduction and Purpose: Noise pollution is one of the important environmental problems that has been on a growing trend in the recent years. This study was conducted to evaluate the level of noise pollution in Omidiyeh city, Iran. Methods: Testo 815 sound level meter was employed to quantify the sound pressure level (SPL). The measurements were conducted during 7-9 am, 12- 14 am, and 19-21 pm, at three locations (one station in each of commercial, residential, and commercial-residential areas), and the results were compared with the standard level of noise pollution. Results: The results indicated that the SPL at all the specified times and areas were higher than the standard level. The mean SPL in commercial, residential, and commercial-residential areas were 72.86, 67.36, and 61.71 dB, respectively, which were 7.86, 7.36, and 6.71 dB higher than the standards of noise in the open air. Conclusion: This study showed that the SPL was higher than standard level, Therefor new approaches should be implemented to reduce the level of noise pollution

Introduction: According to previous researches, working at the airport is one of the most vociferous jobs in the world. Airport workers are at risk of noise induced hearing loss. The present study was done to evaluate the Sound Pressure Level (SPL) in the closest aprons to Ground Safety department at Mehrabad airport and to investigate the effect of airport noise on the employees of this department. .Material and Methods: Evaluation of SPL in the given aprons was done using sound meter and sound analyzer. Measurement stations at specific intervals to the sound source were identified inside and outside of the participants 'workplace and SPL was measured at night and day. The mean estimated values were compared with those presented by Ministry of Health. The annual participants' audiometry information was extracted from medical records. Then a self-administered questionnaire was distributed among the study sample in order to measure quality of noise exposure. The questionnaire was developed based on three general criteria including the knowledge toward the noise pollution, job satisfaction, and the exposure to the noise source and the purpose of this questionnaire was to find the relationship (correlation) between these parameters among the study population. .Result: The measured equivalent for 8 hours noise exposure was obtained 94 dB(A) and no relation was observed between octave band sound of aircraft and recorded audiometry. Analysis of the questionnaire showed that people with more knowledge about noise pollution used more hearing protective equipment. Subsequently, by using more hearing protection equipment the level of hearing loss was reduced significantly (P

Background and aims: Noise pollution in bank, as environment for presentation of financial services, is very important from the viewpoint of comfort aspects. This study aims to assess noise pollution and its effects on subjective fatigue of staffs in the governmental banks. Methods: In this cross sectional study, noise equivalent levels were measured in 20 governmental banks located in Hamadan city using sound level meter TES-1358 during work shift. To determine subjective feeling of fatigue , a standard fatigue questionnaire (with reliability coefficient equal to 0.8) was completed among 167 staffs. The questionnaire has 30 questions which was covered three criteria drowsiness, difficulty of concentration and physical impairment. Staffs sensitivity to noise was also measured using standard scales for noise annoyance. The data was analyzed using statistical tests included Pearson Correlation and Analysis of Variance Results: Noise levels in indoor and outdoor of the studied banks were 62±3.7 dB (A) and 64.7±1.8 dB (A), respectively. Subjective fatigue of staffs in the different classes of noise exposure was significantly difference ( Pvalue =0.0 01). The correlation between staffs sensitivity to noise and subjective fatigue was also significant ( P value =0.0 01, r =0.406 ). Conclusions: The result confirmed subjective fatigue of staffs increased in the different classes of noise exposure . Hence, optimization of the acoustic conditions and increasing staffs and customaries awareness about noise health effects are considered to be very necessary.

The most common sources of environmental noise are human transportation systems which can have catastrophic effects on physiology and behavior of wildlife species. Spatial models of noise propagation from roads in ecological sensitive region could be very useful tools for prediction of roads impacts. The goal of our study was to apply a straightforward, accurate, and affordable approach for modeling noise impacts from Isfahan’s west ringway, which passes through Ghamishloo wildlife refuge. We used the System for the Prediction of Acoustic Detectability noise model (SPreAD-GIS). For this study, land use map, meteorological data, topography map, and noise source characteristics were used as the model inputs. We compared the model results to wildlife occurrences to evaluate how noise effects could impact threatened animals. The key affected species of the study area Goitered gazelle (Gazella subgutturosa) and wild sheep (Ovis orientalis isphahanica), were considered for impact analysis. The results showed that in the areas with noise intensity lower that 20 db the animal has no actions and the area is known as “calm area”, however the areas with noise intensity higher than 20 db is as “disturbance and action” area. The comparison of the results of both species showed that the results vary based on their habitat and behavior, and we found the higher noise impacts on distribution of Goitered gazelle in the study area.

Background and Objective: Noise pollution causes many physiological, psychological, economic and social effects on human life. This issue is more important in the environment of industrial workplaces. This research aimed to adopt the functions of GIS for evaluating and spatial analysis of noises in industrial environments. Materials and Methods: At the initial step, the spatial data for industrial halls were collected and stored as map layers into GIS database. Then, the noise pollution data sampled. The data, including the locations and values of sound pressure levels, were used for the relevant spatial analyses. Results: The analyses included: the estimation of sound pressure levels in different areas of halls and at the given distance from machines, determination of noisy areas, development of sound noise risk map, interpolation of sound pressure level data, prioritization of the sound sources (i.e., machines) for a given point, prediction of sound pressure levels by moving machines, and optimal site selection and distribution of machines. The mean of noise pressure level was 95 dB for knitting hall, 93 dB for spinning hall 1 and 88 dB for spinning hall 2. Conclusion: GIS plays a key role in the assessment of noise pollution in industrial workplaces. It is an appropriate tool to store, analyze, manage, and present all types of sound pressure spatial data. Specifically, the use of such system provides spatial intelligence and could help monitor, detect, control, and solve real word sound noise pollution issues. [ABSTRACT FROM AUTHOR]

Traffic noise pollution is a serious threat to wildlife species, resulting in isolating and reducing the population. The Asian Highway of Tehran-Mashhad, from which a 26.51 km long part is located inside Golestan National Park, is the main source of noise disturbance inside the area. The purpose of this study was to determine the most important criteria for noise pollution of this road; in order to achieve this goal, the Principle Components Analysis method was used. To assess the sound emissions and to study the parameters affecting it, desk studies and field visits were used in a 250- meter buffer zone. A total of 16 variables in three different categories of traffic parameters, geometry parameters and environmental parameters were extracted, andthe circular plots were measured at a radius of 25 m for 15 minutes. The results of PCA showed that six main factors including the speed of light vehicles, the humidity, the altitude above sea level, the number of light vehicles, the distance from the road and the plot slope could justify a total of 72.396 % of the variance of the data. Based on the results, management measures could be taken to reduce the noise pollution based on the extracted criteria, and the noise pollution could be managed more efficiently by spending less time and money. [ABSTRACT FROM AUTHOR]

Introduction: The Power plants are as the major industries that have a large number of workers, providing they health is important. Exposure to occupational noise is the pervasive physical agent in industries like power plants and may impact health and for safety status for people. Determination of the sources of noise in workplaces is important step in noise control plans. This study aimed to assess noise pollution and determine the main sources of noise in a power plant for. .Material and Method: This descriptive cross-sectional study was conducted on the ground floor of the turbine unit of a thermal power plant. Measurements was done based on the ISO-9612 and ISO-11200 standard using by the calibrated sound level meter model TES-1389 on “A” frequency weighting and “Slow” mode for time response. Surfer V.10 software was used for interpolation and noise maps producing. Based on grid method measuring for indicating of noise propagation, we set buffer of danger areas to determine main sources of noise. Also, we used the minimized grid method for measuring and study of noise denotation in vertical surface in each main sources. .Result: The results showed that the measured indoor sound pressure level in all areas where at the risk category of the units. The highest average sound pressure level was belonged to the unit 2, with 93.1 dB(A). We find the feed water pumps were the main sources in all of the studied units. Among the four main components of the main sources, the highest noise levels associated with the main pump and the gearbox section with about 100 9B(L) and dominant frequency of 2000 Hz. .Conclusion: Considering that feed water pumps had major sources in indoor power plant noise pollution, engineering noise control such as providing enclosures is necessary to reduce noise pollution to safe levels in the studied plant it is necessary.

Introduction: Noise is one of the most common health hazards at the workplaces that can cause not only somatic problems, but also adversely affect mental health. The aim of this study was to investigate and evaluate occupational noise exposure and noise annoyance in one of the petrochemical companies. .Material and Method: The study population included 47 people working in Administrative and Manufacturing parts of the petrochemical company. First, dosimetry of production workers and noise frequency analysis of Administrative employees were performed. Then, self-report questionnaire for the assessment of noise annoyance at workplace was completed by the subjects. The questionnaire consisted of three parts: scoring of the noise intensity in the workplace, scoring of the noise annoyance in the workplace and determining the feelings and emotions (e.g. fatigue, sleepiness, and concentration problems) that experienced by subjects during the working day. .Result: The results of noise dosimetry measurements showed that mean eight hour equivalent continuous A-weighted sound pressure level was 86.13 dBA. According to the frequency analysis of office rooms, mean noise level and Preferred Noise-Criteria (PNC) was 69.4 dBA and 62 dB, respectively. The findings of our analysis revealed that 17.9% of administrative staff and 63.2% of manufacturing workers assigned “very high” score to the noise intensity in the workplace. The annoyance score was obtained “very annoyed” by 10% of employees of office section and 42% of manufacturing workers. For noise-related complaints and sensations defined by subjects, 49% of administrative staff and 60% of manufacturing workers marked the “sometimes” and “more” item of the questionary. .Conclusion: Based on the obtained results of investigating the noise level (objective exposure) as well as the noise annoyance (subjective exposure) at the studied company, it is necessary to adopt the management –technical noise reduction measures at manufacturing sectors as the personal noise exposure and environmental noise exposure and also noise personal exposure of administrative staff can be decreased.

Background and Objectives: Noise pollution in cities, as a widespread and worldwide problem, can cause adverse health effects such as hearing loss. Traffic noise, as the most important source of urban noise, can influence many jobs including shopkeepers. The aim of this study was simultaneous assessment of traffic noise pollution and hearing threshold level of shopkeepers in congested area of Behbahan in2014. Materials and Methods: This cross-sectional study was performed in two phases (the first phase: noise measurement and frequencies analysis in 16 high traffic squares and streets in Behbahan and the second phase: the measurement of hearing threshold of 44 male shopkeepers exposed to traffic noise) in 2014. Data analysis was performed by SPSS16 software using one-way ANOVA, one-samples t-test,and independent-samples t-test. Results: Noise equivalent level at all measurement stations and hours was higher than the noise allowable limits in commercial-residential areas. Maximum of sound pressure level and maximum of hearing loss in right and left ears of shopkeepers was related to the frequency of 125 Hz. The results of this study showed that 15.9%, 13.6% and 11.4% of subjects had hearing loss in right ear, left ear,and both ears, respectively. Conclusion: The findings of this study show that noise pollution is high in Behbahan and considering the traffic noise is low frequency, maximum of hearing loss occurred at the frequency of 125 Hz. [ABSTRACT FROM AUTHOR]

Background: The cause of most industrial accidents can be found in not observing the consideration of engineering science completely and human factors at individual or organizational levels. Undesirable noises in working areas, has negative effects on workers’ mental conditions and reduces their pruductivity. Based on these facts, the subject of assessing the noise pollution rate in industrial environments & presenting practical approaches for improving and controlling work conditions was reviewed & implemented in one case study. Material and Methods: For recognizing and assessing the pollution rate in different working stations, noise elevations at different levels were measured by SLM machine and the average pressure elevation of the considered unit noise was calculated. In addition, noise dosage was performed for the employed personnel and the maximum permitted time for working units was measured. To assess the effects of undesirable noises on the employees, the hearing level of all the under-study personnel was reviewed by periodical tests. Results: Input analysis showed server noise pollution in the area of word chips production and the results of measuring noise reduction hearing level of the personnel was an indication of noise pollution in the above mentioned area. After applying the related approaches, the results of periodical noise measurements for the personnel showed that noise pollution of that area was under control. Conclusion: Following the individuals and managerial actions for solving the problem of noise pollution in the wood chips area, the continuous reviews and noise measurement tests, showed that the undesirable effects of the noise on the personnel was under control.

Background and Objective : Noise is considered as a common occupational health hazard in a wide range of occupational settings including oil and gas industries and related companies. This research aimed to assess the environmental noise and personal exposure in a petrochemical plant. Method: First, environmental noise measurement was performed as recommended by ISO9612 (1997) and next, short-term dosimetery was conducted for a 2-hour sampling period, during which individuals worked at Site .Then 4-hour dose was calculated based on 2-hour dose ,and finally 8-hour equivalent level was estimated by 4-hour dose and equivalent sound levels were measured in the resting rooms . Results : The results showed that 8.8% of total stations measured have been in the danger zone and more than 74% of them were in the caution zone. It was found that the Air unit has the higher sound pressure level than the other units and Compression part of Air unit with a mean of 93.28 dB A and the peak level of 101.2 dB A has the highest noise level recorded. According to personal noise dosimetry results, the 8-hour equivalent level in Water, Air and Powerhouse was 81.7, 89.2 . and 82.5 . dB A respectively. Conclusion : The results of environmental and personal noise monitoring suggested that Air unit has the most noise pollution in the petrochemical plant. Therefore, it is necessary to identify the dominant sources of noise and prioritize different units to control the noise pollution of the industry.

Background and Aim: Noise pollution is recognized as a major problem in urban areas. Therefore, the current study was aimed to determine noise pollution indices in Birjand old districts. Materials and Methods: In this cross-sectional and analytical-descriptive study, noise measurement was performed by means of "CEL" sound level meter (model 450.490). Equivalent noise level "Leq 10 min" was measured within four daily periods and within two periods at night, according to the procedures recommended by BS 7445-1-2003, as well as BS 7445-3-1991 standard, at each station. The obtained data was analysed using SPSS software (v 16) by means of statistical tests Pearson and T-test Results: The findings of the study showed that day-night mean sound level (Ldn) was significantly higher than the standard level in all stations (P>0.05). The highest day–night mean sound level and maximum noise level belonged to Motahhary street (72.2 dB) and Taleghani street (85.9 dB). There were signifigant differences between day-night mean sound level and maximum allowable threshold in working day (P

Introduction: Application of agricultural machineries such as tractor has been yielded a considerable development in different agricultural activities and productions. However, noticeable health problems such as noise pollution impact the users of these off-road vehicles. The purpose of this study was to determine the noise level induced by agricultural tractors and to evaluate the driver’s noise exposure level. .Material and Method: The sound pressure levels of three brands of tractor include John Deere, Ferguson and Romani were measured by sound level meter model Tes-1358. The characteristics of place for measuring tractors noise pollution were determined based on the ISO standard No 7216, 5131. The acquired data was analyzed using spss16 software. .Result: The results showed that the highest and the lowest noise level around the tractors were 83.8 dB (A) and 73.9 dB (A) for the John Deere and Romani, respectively. The effect of different transmission gears on the noise level of tractors was not statistically significant Pvalue>0.05. While, the effect of the tractor engine speeds on the noise level was statistically significant Pvalue

Introduction: This study was conducted to assess noise pollution in one of thepetrochemical complex andtakepractical measures to reduce it. Thecompanyis located in site 4 of Mahshahr Special Economic Zone. . Method and Materials: In the first phase of the research, environmental noise was measured to determine the noise levelsin the different sections of the plant and also identify the main sound sources.Then,using the basic acoustic knowledge, aformulahasbeenproposedasan indexof noise control priority to select one section of the plant as the first priority forcontrolling noise. The main soundsource of the selected section wasknownby referring to noise maps and contours and finally its acoustic properties were analyzed. . Results: The results showed that safety caution and danger areasof the plant under study were 16.7%, 74.5% and 8.8% respectively and a major part of the danger zone (about 54%) was related to unit Air. Noise level in 24 percent of the caution zone ranged from80 to 85 dBA and alsoitwas above 90 dBA in 33.4% of danger areas. . Conclusion: Compressionsectionwhich was located in unit Air was knownas first priority based on Noise Control Priority Index.Dryer machineswere the main sound source in this section.