Permissible Noise Levels Research Articles

Evaluation of noise pollution impact on health in Dhaka city, Bangladesh.

The purpose of this research was to look at the interrelation between adult health issues in Dhaka and noise pollution. The methodology involved a cross-sectional survey conducted in five different land use categories, with a sample size of 1,016 individuals. A validated questionnaire that focused on sources of perceived noise pollution and health issues related to noise was used to gather subjective data for the study. Objective noise pollution was evaluated using equivalent continuous sound pressure level (LAeq). Findings revealed noise generated from road traffic are the predominant source of noise pollution, with Thursday evenings during the end of office hours being the noisiest period in Dhaka. All areas in Dhaka exceeded permissible noise levels, posing significant health risks to residents and workers. The study identifies critical gaps in existing noise regulation policies and enforcement. Overall, this study underscores the urgent need for comprehensive noise pollution mitigation strategies, including innovative technologies, real-time monitoring systems, and public awareness campaigns. Further studies in diverse urban contexts are recommended to enhance the understanding of noise pollution's long-term impacts on vulnerable populations.

Noise reduction design of new residential buildings along urban roads-taking a residential district in Foshan as an example

Taking a residential district in Foshan along the city road as an example, the impact of urban road traffic noise on it is studied. Firstly, the data is monitored in the noise field, then three-dimensional simulation models of residential buildings and road distribution are established in Cadna/A software, and noise simulation prediction is carried out according to the actual situation and relevant norms and standards. The predicted noise values of the exterior surface of residential buildings are obtained, which has exceeded the permissible interior noise level for residential buildings. By comparing the application effects of noise reduction measures in buildings, the noise reduction design scheme of new residential buildings along urban roads is finally proposed: the sound insulation doors and windows that meet the requirements are adopted. After the completion of the house, the indoor background noise and the sound insulation performance of the doors and windows are measured. The measured results show that the selection of sound insulation doors and windows is suitable and the indoor noise environment meets the design requirements of noise reduction. The results are helpful to provide technical reference for the noise reduction design and renovation of other residential buildings along urban roads.

Оценка уровней шума в Санкт-Петербургском метрополитене

Purpose: to assess the impact of noise levels in St. Petersburg metro cars. Identify what types of cars used on various metro lines. Determine what types of rolling stock cars used in the metro. Determine how much the service life of the cars affects the noise level in the car. Conduct measurements of noise levels inside the carriages of rolling stock of various types on various metro lines. Correlate the obtained values with the established requirements of SP 2.5.3650–20 “Sanitary rules for the operation of subways” with the values of maximum permissible noise levels in cars. Conduct an analysis of the level of noise impact on humans in the metro and identify possible measures to reduce the noise level in the metro. Methods: measurements of noise levels at various stations and trains were carried out by a special instrumental method, using a digital integrating meter and an Octave 110A sound spectrum analyzer of 1st accuracy class according to GOST R 53188.1. Results: measurements of noise levels carried out in various types of cars on various branches of the St. Petersburg metro. An analysis of the results of field measurements of noise levels for equivalent and maximum levels in the metro shows that permissible noise levels are exceeded in the “Baltiets” car on the red metro line, in car 81-717/714 on the blue metro line; in car 81-717/714 on the purple metro line; in car 81-556.2/557.2/558.2 “Neva” on the green metro line. Practical significance: identification of the obtained data show necessary measures to reduce noise in the metro. Installation of sound-absorbing materials at stations and on trains. Replacing old trains with newer ones.

Indices of vertebral vein discirculation in workers in noise occupaions

Introduction. Occupational sensorineural hearing loss (OSNHL) is a gradual bilateral hearing loss developing over several years as a result of exposure to constant or non-constant noise (mainly high-frequency) at the workplace as one of the main causes in etiology, researchers name a violation of blood supply and vascular stenosis. The purpose of the study is to evaluate the indices of venous dyscirculation under the influence of industrial noise at the early stages of the development of OSNHL. Materials and methods. Twenty two male patients who have been working in conditions exceeding the maximum permissible noise levels for more than 5 years were examined, and the comparison group included 29 healthy male volunteers from 27 to 55 years old who do not work in the production sector. All the subjects were examined by an otorhinolaryngologist, a neurologist, and a therapist. Audiometry was performed on two axes for everyone. Air and bone conduction were performed separately for each ear. All patients underwent a triplex scan of the arteries and veins of the neck and brain in the supine and standing positions. Results. In comparison with the control group of healthy volunteers who did not work in industrial noise conditions, workers in noise occupations had a significant increase in blood flow, which averaged 25.2 cm/sec. When measuring the diameters of the vertebral veins, a tendency to vasodilation was revealed. Limitations. The limitation was the small sample size, due to the low patient turnover at the preclinical stage. Conclusion. The complex effect of noise on the body leads to changes in the wall of the venous network, a violation of venous outflow and can manifest itself not only with clinical complaints, but also in the form of episodic dizziness, cephalgia, which in turn can worsen the course of the development of OSNHL. It is necessary to perform ultrasound dopplerography of the neck veins for all workers of noise occupations at the preclinical stage to assess the risk of OSNHL occurrence.

Multi-Faceted Analysis of Airborne Noise Impact in the Port of Split (III)

Marginal and neglected until recently, noise pollution is a significant topic of sustainable development today. Port noise has become an increasingly critical problem for the environment. The public and the scientific community have gradually become aware of the harmful impact of noise emissions on residents living near port facilities. It coincides with the increase in complaints from the population about excessive noise pollution in ports, especially in residential areas near the cargo terminals in Split. This paper seeks to empirically investigate overall port noise and assess the significance of the reported disturbances. The methodology includes the measurement of noise in zero state conditions, residual noise and noise during specific work processes, and consideration of conditions for possible adjustments of the selected work process during transport operations. The goal is to propose plans for noise reduction by evaluating the results of noise monitoring with the specified limit values, which determine the highest permissible noise levels for industrial and residential zones in the observed area. The values exceed the maximum permitted noise levels during the night. However, this problem can be reduced through operational and technical adjustments in cargo handling processes, acting as objective mitigation measures. The effectiveness of the defined procedure is demonstrated by its application in the Port of Split, contributing to the port’s sustainability located near the residential area.

Impact of Aircraft Noise and Compliance with the Use of Personal Protective Equipment on Hearing Impairment in Pilot Cadets at Indonesian Civil Pilot Academy - Banyuwangi

Noise in the workplace is a health issue in several countries. Similarly, in the aerospace industry, advanced aircraft, whether for civilian transportation or military purposes, pose risks due to exposure to aircraft noise, which passengers are continuously subjected to at relatively higher intensities and for prolonged periods. The problem of this research is to identify, reduce, and prevent the impact of aircraft noise and compliance with the use of personal protective equipment (PPE) on hearing impairment among cadet pilots at the Indonesian Aviation Academy in Banyuwangi. The research objective includes collecting medical records of 57 cadets, measuring aircraft noise levels, and conducting a questionnaire survey. The method used in this study is descriptive quantitative, with 57 respondents. Data analysis was performed to determine the compliance of cadets with PPE usage at the Indonesian Aviation Academy in Banyuwangi. The results show that the noise produced by the aircraft operated by the academy exceeds the permissible noise level (PNL), and the questionnaire results indicate low compliance with PPE usage. However, medical record data reveal that the majority of cadets still have normal hearing, with only 12.3% or 7 respondents categorized as having mild hearing impairment. These findings imply a positive and significant influence of aircraft noise level and PPE compliance on hearing impairment among trainees.

Smartphone-Facilitated In-Situ Hearing Aid Audiometry for Community-Based Hearing Testing.

Hearing loss prevalence is increasing, with an estimated 2.5 billion people affected globally by 2050. Scalable service delivery models using innovative technologies and task-shifting are World Health Organization priorities to improve access to hearing care, particularly in low- and middle-income countries. Smartphone-facilitated audiometry in the community using hearing aids covered by noise-attenuating ear cups ("in-situ") could support more accessible hearing care when provided by less trained individuals such as community health workers (CHWs). This study aimed to determine the validity of this method for potential hearing aid fitting. Study objectives included determining the maximum permissible ambient noise level (MPANL), inter-device reliability, clinical threshold accuracy, reliability, and performance in real-world settings. Experiment 1: 15 normal-hearing adult participants were evaluated to determine MPANLs for circumaural Peltor 3M earcups covering Lexie Lumen hearing aids with smartphone-facilitated in-situ audiometry. MPANLs were calculated by measuring the difference in attenuation between thresholds obtained with standard headphones and in-situ hearing aids. Experiment 2: Pure-tone frequency and intensity output of 14 same-model Lexie Lumen hearing aids were measured to determine inter-device reliability. Pure-tone stimuli were measured and analyzed to determine sound pressure levels in decibels and pure-tone frequency when connected to a test box 2cc coupler. Experiment 3: 85 adult participants were tested in a sound booth to determine the accuracy of automated in-situ pure-tone audiometry (PTA) compared to clinical PTA (500, 1000, 2000, 3000, 4000, 6000 Hz) facilitated by an audiologist. The first 39 participants were tested twice to determine test-retest reliability. Experiment 4: In a community setting, 144 adult participants were tested with automated in-situ audiometry facilitated by CHWs using a smartphone app. These participants were subsequently tested with automated mobile PTA (500, 1000, 2000, 4000 Hz). An additional 44 participants were tested twice to determine test-retest reliability. Experiment 1: MPANLs of the Peltor 3M earcup-covered hearing aids were higher than standard headphones across all frequencies, ranging from 24 to 47.3 dB SPL. Experiment 2: Inter-device performance reliability was high, with all inter-device differences across all intensities and frequencies less than 3 dB. Frequency output was consistent and differed less than 0.7% between devices. Experiments 3 and 4: 85.2% and 83.3% of automated in-situ audiometry thresholds were within 10 dB of thresholds obtained in the sound booth and in a community setting, respectively. Acceptable test-retest intraclass correlation coefficient (ICC) was evident across all thresholds obtained in a sound booth (ICC = 0.85 to 0.93) and in a community setting (ICC = 0.83 to 0.97). Smartphone-facilitated in-situ audiometry allows for reliable and valid community-based testing. A simple smartphone user interface and automated in-situ audiometry allow CHWs with minimal training to facilitate the testing. With the additional capability to program hearing aids via the smartphone after the initial test, this approach would have the potential to support widespread access to personalized hearing aid fittings facilitated by CHWs in low- and middle-income countries. This approach also supports self-fitting options based on in-situ thresholds, enabling testing and fitting via over the counter hearing aids.

Determining the impact of noise exposure of mining enterprises’ workers

This study investigated one of the main harmful factors at work, namely the impact of noise exposure on employees. The study was conducted in several stages. At the first stage, an on-site measurement was carried out using a calibrated sound level meter and a special smartphone application in the immediate vicinity of the ore grinding mill. It was found that the noise level is not constant. At the second stage, a mathematical dependence of the noise measurement results on the mill operating time was obtained to compare the measurement accuracy of the sound level meter and the app. As a result, it was determined that the application has sufficient accuracy compared to the calibrated instrument. The third stage resulted in the calculation of the risk of hearing loss for employees from noise exposure at workplaces based on the measurements of the calibrated sound level meter. The calculations showed that the level of this risk is high. At the fourth stage, personal protective equipment was selected using the relevant guidelines from NIOSH and EU-OSHA, as well as considering the results of field measurements, the maximum permissible noise level established by state sanitary standards, and the level of hearing loss risk.

Шумовое загрязнение территории многоэтажных жилых застроек города Ставрополя

The article provides measurement results and an assessment of the noise load on the territory of the «Perspektivny» and «Rossiysky» residential complexes in Stavropol. Noise measurements were carried out in the spring-summer and autumn-winter periods of 2022–2023. The measurement results are presented as average noise exposure levels. Based on the data obtained, a mathematical model of the propagation of noise from traffic flow during the deciduous and leafless period was built. To conduct a study and assess the noise load in a multistorey building on the territory of the South-Western district of Stavropol. The measurement of the noise load was carried out in accordance with GOST 23337-2014 “Noise. Methods for measuring noise in residential areas and in residential and public buildings”. To analyze and compare the data obtained with the maximum permissible value, SanPiN 1.2.3685-21 “Hygienic standards and requirements for ensuring the safety and (or) harmlessness of environmental factors for humans” was used. The measurement results revealed excess of maximum permissible noise level on the territory of the residential complex «Perspektivny» and «Rossiysky», and the houses within the residential complex «Perspektivny» suffer most from the proximity of the roadway and the absence or partial landscaping. Noise values were recorded near residential buildings in the range of 70 dBA. On the territory of the residential complex “Rossiysky”, high indicators are found on the sidewalk near the South-Western bypass. No excess of maximum permissible noise load level was noticed directly at the houses. The resulting mathematical model reflects the dependence of the noise level on the presence and absence of foliage and the density of traffic flow. Based on the data obtained, we can conclude that the residential complexes «Perspektivny» and «Rossiysky» are subject to significant noise pollution. This can be attributed to shortcomings in the planning of territory development and the increase in the number of vehicles.

백색잡음 환경에서 귀덮개 사용이 변조이음향방사 신호대잡음비에 미치는 영향

Objective: Earmuff has been shown to attenuate noise and may be useful in boothless audiometry. This study aimed to determine the effect of earmuff use on the signal-to-noise ratio of distortion production otoacoustic emission (DPOAE) in a white noise environment.
 Method: Participants were 19 young, healthy men and women (38 ears) aged 22.45±1.31 years. The hearing threshold level in 1, 2, 3, and 4 ㎑ did not exceed 15 ㏈ HL. DPOAE was performed at four points per octave in the range 842 to 9,509 ㎐ based on f2. After obtaining the baseline (Base), white noise was presented at 10 ㏈ intervals from 40 to 70 ㏈ SPL. DPOAE was obtained without (WN) and with earmuff (Earmuff). The maximum permissible ambient noise level (MPANL) of the WN and Earmuff were compared (paired t-test). Signal-to-noise ratio (one-way repeated measures ANOVA) and PASS rate (Chi-square test) between WN, Earmuff and Base at the overall frequency, mid-frequency (mid-3-freq), and high-frequency (hi-3-freq) bands were analyzed.
 Results: There was a difference of 22.19 ㏈ in MPANL between Base and WN (p=.000). There was a significant difference in the SNR between Base and WN from 40 ㏈ SPL, and in PASS rate between Base and Earmuff from 60 SPL (p<.005).
 Conclusion: In DPOAE, earmuff increase MPANL, which enables recording at up to 60 ㏈ SPL. The SNR in the high-frequency band is more preserved than in the lower, Therefore, it seems advantageous for early detection of cochlear microstructural changes due to noise or aging.

HEALTH RISK AS A CRITERION TO ESTIMATE POPULATION SAFETY IN AN AIRPORT ZONE

The paper considers and tests methodological approaches to assessing public health risks when establishing and using the sanitary (seventh) subzone in an airport zone. Testing was performed at a large civilian airport in Russia. It involved outlining noise contours in accordance with the ICAO methodology. The aviation noise contours were verified with the results produced by instrumental measurements. Acoustic exposure was calculated through assessing averaged daily equivalent noise level (LDN) that was equal to 65 dBA. Health risk assessment showed that long-term exposure primarily affected the cardiovascular system: moderate risks would occur by 23 years; high, by 55 years; and very high, by 63 years. Identified health disorders may become apparent through elevated blood pressure, heart diseases, myocardial infarctions and others.
 Background. It is quite common to locate certain objects within an AZ that are subject to sanitary-epidemiological standardization. Use of any AZ for location of such objects should be well grounded and this is a significant issue occurring when the sanitary (seventh) subzone is established. In particular, this concerns equivalent outdoor noise levels and equivalent and maximum permissible indoor noise levels.
 Purpose. Our research goal was to test the suggested approach to health risk assessment within the boundaries of an aircraft zone.
 Materials and methods. Our research object was a large civil aviation airport located in the temperate zone with an average daily number of landings and takeoffs being about 200. At the exposure assessment stage, we calculated aircraft noise contours by using a certified software package that was based on «Recommended Method for Computing Noise Contours Around Airports» (ICAO Doc 9911-2018). We took an equivalent averaged noise level (LAday, dBА) as an indicator applied to estimate population exposure to a harmful factor.
 We performed continuous AN measurements on a territory that was planned for development. This AN occurred due to AC takeoffs and landings with more than 600 AC flights detected during the measurement period. This determined effects produced by AN on the examined territory. Assessment of “exposure – response” and “exposure – effect” relationships involved using recurrent risk growth equations built on conventional pair mathematical models. This risk was measured within a range from 0 to 1 and scale was considered when giving its estimates.
 Results. This value was calculated based on maximum noise levels established during a single aircraft flight when it took off or landed along a route that was the most significant for determining exposure to aircraft noise. We also calculated equivalent noise levels at day and at night that corresponded to flight intensities typical for normal airport operations (2019). These levels were LAeq.day = 66,0 dBA (“takeoff”), LAeq.night = 52,0 dBA (“landing”).
 Health risk assessment indicated that long-term (chronic) exposure to average daily noise LАd = 65 dBA primarily produced effects on the cardiovascular system. This created moderate risks by the age of 23 years; high risks, 55 years; and extremely high risks, by 63 years.
 We established that living for more than 15 years in an airport zone with identified noise levels could result in negative health outcomes.
 Conclusion. Overall, we have confirmed that health risk assessment should be considered an important instrument for substantiating boundaries of a zone influenced by an airport. Results produced by such assessment are a key criterion in determining how to use a territory near an airport in future as regards locating capital objects there including residential areas and their exploitation.

Об одном из подходов к прогнозированию и повышению шумопоглощения в кабинах транспортно-технологических машин

Noise is one of the main harmful production factors in the mining industry. The results of a hygienic assessment of working conditions indicate that exceeding the maximum permissible noise levels in 50 % of cases is recorded at the workplaces of drivers of the transport and technological machines. One of the efficient measures to reduce medium- and high-frequency noise in the cabins of transport and technological machines is the use of noise-absorbing upholsteries mounted on their metal panels. The article presents a computational and experimental procedure based on determining the reverberation coefficient of sound absorption of flat-sheet pressed samples of materials manufactured using the production technology of serial molded upholsteries. The material samples contained a base layer of open-cell polyurethane foam, a reinforcing layer of fiberglass, a thermally activated adhesive layer, a front layer of needle-punched fabric, and a back layer of non-woven fabric. The values were determined related to the sound absorption coefficient of flat-sheet pressed samples of materials manufactured using representative technology. The measurements were carried out with different sizes of air gaps relative to the reflective surface. As an example, the results of calculating the equivalent sound absorption area of the roof lining of a truck cab are considered. The obtained values of the equivalent sound absorption area for the original design option are below the target values for this part by up to 31 %. The original version was modified by changing the thickness of the molding of the blank and its location relative to the metal panel of the cabin without changing the material and design. As follows from the calculation results, the values of the equivalent sound absorption area of the roof lining in the modified version ensure that the target requirements are met.

Analysis of Traffic Noise Levels on Land Use in Jos Metropolis, Nigeria

Traffic noise in urban areas has always been a global issue. This study focuses on the land use analysis of traffic noise levels in the Jos Metropolis. The study was conducted in Jos Metropolis, Plateau State, Nigeria. Twenty-five (25) road corridors were sampled for the study. Measurement points were randomly selected along the road corridors. Traffic noise levels were collected using Sound Level Meter. The sound level meter was positioned at a distance of 6.5 m from the centreline of the nearest travel lane of the road and was held at about 1.5 m high from the ground level. The traffic noise levels data were collected three times a day during peak hour periods from Monday to Saturday. Noise data were measured for 15 minutes at an interval of 6 seconds in each measurement point for six days, making a total of 18 measurements per location. Data sourced from the field were analysed using Mean, Standard Deviation and Analysis of Variance (ANOVA). The study revealed that traffic noise levels in Jos Metropolis in the various land uses exceeded the maximum permissible noise levels recommended by WHO and FEPA. The study recommended the dispersal of land uses through land use allocation

Evaluating the Effectiveness of Speed Humps Related to Speed Profile and Noise Profile

Speed humps are an effective traffic calming measure to improve the safety of road users. On the other hand, speed humps have certain drawbacks, such as increasing emergency response time, causing damage to cars, and high noise levels due to excessive traffic. These impacts further vary with different hump profiles. Thus, the primary objective of this research is to investigate how the geometric profile of speed humps affects vehicle speed and noise level. The secondary objective is to find the Level of Service in the presence and absence of a speed hump by using VISSIM microsimulation. In this study, Lake Drive Road, Nawala, was selected with four different speed hump profiles. The Sound Meter smartphone application was used for noise monitoring. A drone camera footage was utilized to capture vehicle flows while speed trajectories of each vehicle were developed using tracking software. The developed speed profiles were used for the simulation purpose. Then, a Multiple Linear Regression (MLR) model was developed and validated to predict the hump height for the desired speed reduction and desired noise level for each selected four-vehicle category. Further, the average noise levels were found to be higher than the Central Environmental Authority's permissible noise level, and it increases with the height of the hump. It was also observed that as the height of the hump increases, vehicle speed decreases. The largest speed reduction, 42.13 %, was observed in passenger cars, while the lowest speed reduction, 23.5 %, was observed in motorcycles. Therefore, speed analysis findings reveal that passenger cars have a significant speed reduction when compared to other categories. However, the average speed reduction for all vehicles was identified as 33.85 %, and VISSIM simulations revealed that the average Level of Service (LOS) drops to LOS C from LOS A due to the presence of the speed hump. KEYWORDS: Level of Service, Speed hump profile, Speed hump, VISSIM

Measurement and Analysis of Noise Levels: A Study of Selected Pubs in Calabar, Nigeria

This research involves the assessment of noise levels in pubs operating in Calabar, Nigeria, to investigate their compliance with the permissible noise level recommended by the National Environmental Standards and Regulations Enforcement Agency (NESREA), Nigeria. A Bam and Kom (BK) Precision 732 digital sound level meter placed on a tripod was used for the measurement of noise levels for three consecutive months, from 6:00pm to 10:00pm. The measured data were subjected to descriptive statistics using excel spreadsheet and the results were presented in the forms of graphs, bar chart and in tabular form. Average equivalent noise level obtained for pubs A, B, C, D and E were 86.5dB, 75.7dB, 75.9dB, 90.0dB and 81.9dB, respectively. Results show that all the pubs under study were in excess of the permissible noise level recommended by NESREA.

Boothless audiometry: Ambient noise considerations

Ambient noise in the test environment will impact signal detection during hearing threshold measurements due to psychoacoustic masking effects. Technical standards specify the maximum permissible ambient noise levels (MPANLs) for use during audiometric testing. MPANLs are dependent on several factors, including transducer characteristics (supra-aural, circumaural, type of ear cushions or earphone enclosures, and insert earphones), the nature of the hearing test being performed (air conduction vs bone conduction and threshold test vs screen at a suprathreshold level), and measurement instrumentation. The nature of the ambient noise (spectrum and constant vs variable) at the test site must be determined and continually accounted for during the boothless hearing test procedure. Ambient noise monitoring procedures are reviewed and examples of ambient noise characteristics in real-world settings, where hearing testing might be performed outside of a sound-treated environment, are provided. Practical considerations are presented, including examples of available tools for ambient noise monitoring, selection of test locations, and transducer attenuation. These are discussed in the context of calculating MPANLs and how best to ensure that ambient noise levels are not negatively impacting the validity of hearing thresholds.

Акустическое загрязнение улично-дорожной среды автомобильным транспортом

The article analyzes the noise negative impact of motor transport on people. The existing methods of reducing the noise impact from vehicles are described. The results of field studies of the intensity of traffic flows and measurements of the noise exposure level in the city of Naberezhnye Chelny are presented. A significant excess of the maximum permissible noise level is specified. A possible option for improving the environmental situation on the considered section of the road network due to the installation of noise screens is proposed.

Determination of the Characteristics of Noise-Reducing Materials for Motor Transport

Nowadays more and more attention is paid to the research of noise emitted by motor transport because of the introduction of lower permissible noise levels for automobiles on a legislative level. One of the effective methods to reduce automobile noise is the use of noise-reducing materials (noise-absorbing, soundproofing, vibration damping) in its design. The measuring setup for determining the characteristics of noise-reducing materials is reviewed in the article.

Noise from mechanical ventilation systems in residential buildings

Modern people spend up to 90% of their time indoors. Therefore, the research aimed to identify noise sources from engineering equipment, and developing recommendations for their elimination was an urgent scientific task. The paper considers the problem of noise pollution from mechanical ventilation systems in residential buildings. One of the most common errors in conducting acoustic calculations is the exclusion of noise generated by regulating devices, which significantly contribute to the final sound pressure levels at the outlet of the ventilation grate. The results of field studies are presented; they prove the need to normalize permissible noise levels in non-residential premises of an apartment and develop a legislative framework for measuring noise in hybrid ventilation systems. Practical recommendations for designing exhaust ventilation systems with a prefabricated vertical duct have been developed. It has been found that the replacement of throttle valves with iris diaphragms and the installation of silencers on prefabricated channels and apartment withdrawals, given the influence of the vortex zone from control devices, reduce the overall noise level from the ventilation system.

Prawne aspekty hałasu „sąsiedzkiego” – cz. I (odpowiedzialność administracyjna)

Legal aspects of “neighborhood” nuisance – Part One (administrative liability) The study concerns the legal aspects of a nuisance to which a person may be exposed at their place of residence. The authors analyze the issue in terms of the provisions of the act of April 27, 2001 on the environmental protection law. They refer to such issues as permissible levels of noise in the environment; the decision on permissible noise levels; suspension of the use of a noise-emitting installation; ordering an individual whose activity adversely affects the environment to perform actions aimed at reducing the negative impact on the environment and its threat or restoring the environment to its proper state; halting activities that cause deterioration of the environment to a significant extent or threaten human life or health; establishing restrictions on the duration of operation of installations or use of equipment from which the emitted noise may adversely affect the environment, as well as prohibiting the use of sound installations or equipment in certain areas.