Average Noise Level Research Articles

An Analytical Perspective to Evaluate the Noise Level and Respective Spatial Noise Mapping Induced by Metro-Rail Movement in Dhaka City

Metro rail systems, which provide efficiency and speed, have revolutionized urban travel. However, the subsequent influence on environmental acoustics, notably noise pollution, needs further examination. This study evaluates noise pollution from the Dhaka metro rail along an 11.7 km segment, focusing on 27 monitoring points across commercial, mixed, and residential areas. Sampling on working and non-working days, representing a three-shift day, revealed average morning noise levels during working days (72 dB to 78.7 dB), increasing in the afternoon (76.2 dB to 83.6 dB), and peaking in the evening (80.8 dB to 89 dB). On non- working days, morning levels ranged from 69.1 dB to 73.1 dB, with afternoon and evening levels at 75.2 dB to 81.6 dB and 75.2 dB to 84 dB, respectively. Identified noise levels at specific locations underscored the need for managing metro rail-induced noise pollution, especially in commercial zones during working days. To address this issue, the research recommends implementing noise reduction measures and planning strategies to minimize disturbances in sensitive areas, ensuring a sustainable and harmonious urban environment.

Machine Learning-based GIS Model for 2D and 3D Vehicular Noise Modelling in a Data-scarce Environment

Abstract Vehicular traffic significantly contributes to economic growth but generates frictional noise that impacts urban environments negatively. Road traffic is a primary noise source, causing annoyance and interference. Traditional regression models predict two-dimensional (2D) noise maps, but this study explores the impact and visualization of noise using 2D and three-dimensional (3D) GIS (Geospatial Information Systems) functionalities. Two models were assessed: (i) a 2D noise model for roads and (ii) a 3D noise model for buildings, utilizing limited noise samples. Combining these models produced a comprehensive 3D noise map. Machine learning (ML) models—artificial neural network (ANN), random forest (RF), and support vector machine (SVM)—were evaluated using performance measures: correlation (R), correlation coefficient (R2), and root mean square error (RMSE). ANN outperformed others, with RF showing better results than SVM. GIS was applied to enhance the visualization of noise maps, reflecting average traffic noise levels during weekday mornings and afternoons in the study area.

Abstract P319: Effects of Environment and Noise on Blood Pressure Readings: The (Decibel(s)) Trial

Background: While guidelines emphasize quiet settings for blood pressure (BP) measurement, large-scale hypertension screening is often conducted in noisy, public spaces (e.g., health fairs). However, the influence of noise and environment on BP readings is unknown. Methods: We conducted a randomized crossover trial of community dwelling adults in Baltimore, MD to determine the BP effect of noise and public environment. Participants were randomly assigned to the order of triplicate BPs in 3 spaces: private quiet office (private quiet 1 [reference]); noisy public space (public loud); noisy public space + earplugs (public quiet). To account for intrinsic BP variability, all participants underwent a 4th set of BP measurements in a private quiet office (private quiet 2 ). Between each set of triplicate BPs with a WelchAllyn ProB 2000 device and appropriately sized cuff, participants walked for ≥2 minutes, rested for 5 minutes, and had arm/back/feet supported. We conducted difference in difference analysis, overall and stratified by baseline SBP (≥ vs. < 130mmHg) and age (≥ vs. <60yrs). Results: N=108, mean age 56 (SD 17) yrs (55% ≥60 years), 91% Black race, and 44% female. 45% had SBP≥130mmHg. Mean private quiet 1 and private quiet 2 BP was 129/74 and 127/74 mmHg (SBPΔ -1.6 (SD 7.1)/DBPΔ -0.2 (SD 4.0)). The average noise level in public loud was 74 db and in private quiet was 37 db. Public loud and public quiet BPs were slightly different than private quiet 1 BPs, with difference in differences minimal (Table): [Public loud: SBPΔ 0.97 mmHg (95%CI: -0.61, 2.55)/DBPΔ 1.86 mmHg (95%CI: 0.94, 2.78); Public quiet: SBPΔ 1.72mmHg (95%CI: 0.05, 3.39)/DBPΔ 1.66 mmHg (95%CI: 0.79, 2.54)]. The patterns were generally consistent across subgroups by SBP and age. Conclusion: BP readings in noisy public spaces resulted in small overestimation of BP compared to readings in a quiet private office, but the difference was minimal. Large-scale hypertension screening programs in public loud places may be an acceptable option, especially in low resource settings.

GPS displacement dataset for the study of elastic surface mass variations

Abstract. Quantification of uncertainty in surface mass change signals derived from Global Positioning System (GPS) measurements poses challenges, especially when dealing with large datasets with continental or global coverage. We present a new GPS station displacement dataset that reflects surface mass load signals and their uncertainties. We assess the structure and quantify the uncertainty of vertical land displacement derived from 3045 GPS stations distributed across the continental US. Monthly means of daily positions are available for 15 years. We list the required corrections to isolate surface mass signals in GPS estimates and screen the data using GRACE(-FO) as external validation. Evaluation of GPS time series is a critical step, which identifies (a) corrections that were missed, (b) sites that contain non-elastic signals (e.g., close to aquifers), and (c) sites affected by background modeling errors (e.g., errors in the glacial isostatic model). Finally, we quantify uncertainty of GPS vertical displacement estimates through stochastic modeling and quantification of spatially correlated errors. Our aim is to assign weights to GPS estimates of vertical displacements, which will be used in a joint solution with GRACE(-FO). We prescribe white, colored, and spatially correlated noise. To quantify spatially correlated noise, we build on the common mode imaging approach by adding a geophysical constraint (i.e., surface hydrology) to derive an error estimate for the surface mass signal. We study the uncertainty of the GPS displacement time series and find an average noise level between 2 and 3 mm when white noise, flicker noise, and the root mean square (rms) of residuals about a seasonality and trend fit are used to describe uncertainty. Prescribing random walk noise increases the error level such that half of the stations have noise > 4 mm, which is systematic with the noise level derived through modeling of spatially correlated noise. The new dataset is available at https://doi.org/10.5281/zenodo.8184285 (Peidou et al., 2023) and is suitable for use in a future joint solution with GRACE(-FO)-like observations.

Assessment of noise complaints as an indicator of long-term effects of aircraft noise on communities surrounding aerodromes

Aircraft noise is considered by many as the most burdensome part of aircraft operations. Communities neighbouring airports often express concerns about the possible health effects of chronic exposure to noise. To quantify the long-term effects of environmental noise exposure, researchers often use the metric of annoyance. Annoyance is widely considered to be the most well-corroborated health effect of aircraft noise and a moderating factor for other suspected health effects. Annoyance can also be correlated to average cumulative noise levels, such that higher levels of chronic noise likely evoke higher levels of annoyance within the population. Annoyance data is typically collected using extensive surveys and/or interviews, which are costly and time-consuming. In the absence of annoyance data, complaints are often used as a proxy for annoyance. This research used complaint, noise and annoyance data to demonstrate that complaints do not equate to annoyance, nor do they correlate to cumulative noise metrics. Thus, while complaint data may prove useful in analyzing short-term response to operations, it should not be relied upon for the assessment of long-term impacts from aircraft noise exposure, nor should it be used to direct noise and annoyance mitigation initiatives.

Analisis Keterkaitan Antara Aktivitas Kendaraan Bermotor dengan Tingkat Kebisingan: Studi Kasus di Jalan Gatot Subroto, Kota Palu

The elevation of mobility in Palu has evolved into a new noise issue. Noise from motorized vehicles has quite an impact on the tranquility of areas that directly intersect with the highway. Gatot Subroto Axis Road is an instance of a congested road as public facilities such as educational institutions take the crowd of the area. The study aims to analyze the relationship of vehicle activities toward noise level at Gatot Subroto. The research method uses field measurement by a sound level meter (SLM), tripod, and counter. Noise sampling standards refer to SNI 8427:2017 regarding measuring environmental noise levels. Data was collected for one day on weekdays and weekends with three take times at three sampling points. Noise level analysis is carried out using frequency distribution. The next data analysis is to look for the equivalent noise level or LAeq. The noise level points varied between 71,6 dBA-84,02 dBA. The traffic volume reached a peak at 853. The p-value was 0,72 which was above 0,05. The regression test was Y=0,0048x+72,904, and R2 showed 0,15 points, which means that 15% of the noise level was affected by traffic volume. In conclusion, the average noise level at Gatot Subroto Axis Road exceeded the quality standards set according to the Decree of the Minister of State for the Environment No. 48 of 1996, which is 55 dB(A). Despite no significant difference in noise levels on weekdays and weekends based on the t-test, the noise level is affected by traffic volume. Noise from motorized vehicles has quite a big impact on the tranquility of areas that directly intersect with the highway. he limitation of this research is the limited amount of data due to the small number of research points and the insufficient number of days, so further research is needed.

Structural, acoustical, and thermal evaluation of an experimental house built with reinforced/hollow interlocking compressed stabilized earth brick-masonry

With the increasing demand on affordable construction that addresses the global challenges of the modern world, earthen construction is being reintroduced and investigated as a potential sustainable and affordable building method. Compressed stabilized earth blocks (CSEBs) are a common form of enhanced earthen building materials. Previous studies focused on the structural performance of CSEB walls and prisms consisting of one type of bricks with the same mixture, analyzed their thermal and acoustic properties as units only, or evaluated the thermal performance of solid unreinforced CSEB masonry.The present research is the first complete structural, acoustical, and thermal investigation of an experimental house built with a novel reinforced/hollow interlocking compressed stabilized earth brick-masonry (ICSEB) using varying stabilizer contents, compliant with the Egyptian code for building with stabilized soil—Part One: Building with compressed stabilized soil units (EG-SE2016). Methods depend on experimental testing, codified theoretical calculations, finite element analysis, and live measurements. According to the structural experimental testing program, reinforcement was found to triple the load bearing capacity of ICSEB columns and, although minimal rebars were used in the ICSEB walls, it has improved their load bearing capacity by 23% for single walls (125 mm) and 58% for double walls (250 mm). In addition, doubling the thickness of the unreinforced ICSEB walls increased the load bearing capability by 164%, while raising the thickness of the reinforced wall from 125 mm to 250 mm increased the load bearing capacity by more than threefold (3.38). Based on the codified theoretical calculations and findings of the finite element analysis, it is safe to recommend reinforced double ICSEB walls as a reliable construction for a two-story residential building. Acoustically, double ICSEB walls attained the noise reduction index value of 40 dB, which is required by the Egyptian code for acoustic insulation and noise control in residential buildings, to protect against the average outdoor noise levels of 65–70dBA. Thermally, reinforced double ICSEB walls kept the indoor air temperature and relative humidity values within the thermal comfort zone, 23.9–25.7 °C and 28–36%, respectively, despite the fluctuating outdoor temperatures and relative humidities (16–37 °C and 7–88%, respectively). Indoor air temperatures were 1.5–2 °C lower than those of concrete masonry walls. Additional research is required to evaluate resistance to environmental aspects, such as exposure to water, wind, and corrosion, and to further investigate their thermal and acoustical properties.

NOISE IMPACT TO STUDENTS OF ROADSIDE PRIMARY SCHOOLS AT RAJSHAHI CITY IN BANGLADESH

A high level of noise in classroom impairs verbal communication of students, which have negative effects on the cognitive performance. The high noise can also limit episodic memory of students. In this context, this study was conducted to measure the noise levels and its impact to students in selected roadside government primary schools in Rajshahi City, Bangladesh during May to November, 2022. The noise level was measured with the help of a digital sound level meter and a questionnaire survey was conductedamong the studentsto evaluate the perception of noise. The results show that the average noise levels (Leq) in the roadside primary schools varied between the 74.1 and 80.1 dBA, with maximum noise 108 dBA and minimum 57.2 dBA. These noise levels are higher than the permissible rangeof 35 dBA recommended by the WorldHealth Organization (WHO).The high levelof noise was foundto school adjacentbusy road. Duringnoise impact study,the majority of students (70%)expressed that their school are noisy “very much”. They indicated that outside factors are responsible for excess noise in school premises. About half (51.7%) of the students responded that noise distracted their attention from the lesson and only 1% of students suffered from moderate headaches due to noise pollution. In terms of immediate reaction to excess noise, the majority of students (62.5%) had to cover their ears with hands to prevent noise hearing.

Noise Level Evaluation at Major Markets in Calabar, Nigeria

The aim of this study was to determine the prevailing noise levels at major markets in Calabar, Nigeria. Data was collected by measuring noise levels in three different markets using RS232 digital sound level meter with measuring range of 32- 80 dB for low range, 50 – 100 dB for medium range and 80-130dB for high range and the analysis was done using OriginPro software. The results obtained were compared with the World Health Organization regulatory standard and it showed that the average daily noise level value produced at Watt and Marian markets were 73.0 dB and 71.5 dB individually, which were beyond the safe limit recommended by the World Health Organization (WHO) for commercial areas while the daily average noise level produced at Goldie market was moderate and within the safe limit.

Analysis of noise levels in the neonatal intensive care unit: the impact of clinical microsystems.

Reorganization of neonatal intensive care by introducing clinical microsystems may help to allocate nursing time more appropriately to the needs of patients. However, there is concern that cohorting infants according to acuity may enhance noise levels. This single-center study investigated the impact of reorganization of neonatal intensive care unit by implementing clinical microsystems in a Level III NICU on environmental noise. This prospective study measured 24-h noise levels over a period of 6months during pre- and post-implementation of microsystems cohorting infants of similar acuity. Comparative analyses of the mixed acuity (i.e., before) and the cohorting (i.e., after) model were performed by creating daily profiles from continuous noise level measurements and calculating the length of exposure to predefined noise levels. Compared to baseline daytime measurements, noise levels were 3-6 dBA higher during physician handover. Noise levels were 2-3 dBA lower on weekends and 3-4 dBA lower at night, independent of the organizational model. The introduction of clinical microsystems slightly increased average noise levels for high-acuity pods (A and B) but produced a much more substantial decrease for low-acuity pods (E), leading to an overall reduction in unit-wide noise levels. Conclusion: Our data show that noise levels are more driven by human behavior than by technical devices. Implementation of microsystems may help to reduce noise exposure in the lower acuity pods in a NICU. What is Known: • Excessive noise levels can lead to adverse effects on the health and development of premature infants and other critically ill newborns. • The reorganization of the neonatal intensive care unit following the clinical microsystems principles might improve quality of care but also affect noise exposure of staff and patients. What is New: • The transition from a mixed -acuity to cohorting model is associated with an overall reduction in noise levels, particularly in low-acuity pods requiring less nursing care. • Nevertheless, baseline noise levels in both models exceeded the standard permissible limits.

Experimental Investigation on Noise and Vibration of an Internal Combustion Engine with Oxyhydrogen Decarbonization

<div>Internal combustion engines are prone to get carbon deposits or residue which accumulate due to incomplete fuel combustion. This can have adverse effects on engine efficiency and performance. Engine decarbonization is one of the recent technologies in automobile maintenance, which involves the removal of carbon deposits or residue from various components within the internal combustion engine, including valves, pistons, cylinder heads, and combustion chambers. Decarbonization methods typically utilize specialized cleaning agents or additives to dissolve and eliminate these carbon deposits claiming to enhance engine performance and restoring optimal functionality. This article focuses to study the effects of engine decarbonization on noise and vibration of an IC engine. Oxyhydrogen (HHO) carbon cleaning machine has been used for decarbonization of the engine. This research addresses a contemporary concern in automotive maintenance by investigating the potential benefits of decarbonization in reducing noise and vibration levels. The results obtained from the data analysis provide insights into the effectiveness of the HHO carbon cleaning in improving engine performance. After decarbonization, the average noise levels have been observed to be decreased by an average of 3.28%, with a maximum reduction of 8.42% at a specific location and RPM value. Additionally, the vibration levels decreased by an average of 3.44%, with a maximum reduction of 16.38% at a particular location and RPM value.</div>

Association between occupational noise-induced hearing loss and genotoxicity among textile factory workers

Background/aimHearing loss caused by exposure to noise is still among the most prevalent health risks for industrial workers. This study aims to evaluate the relationship between Shebien El-kom textile factory workers’ occupational noise exposure, genotoxicity, and noise-induced hearing loss.MethodsThis cross-sectional case–control study was performed in a textile industry in Shebin Elkom, Egypt. The participants of this work were 36 exposed male workers from the spinning section of the textile factory and 36 subjects as the control male group from administrative staff in the same factory, in the age range of 25–45 years. A pure-tone audiometer and portable sound level meter were utilized for the measurement of hearing threshold and noise level, respectively. Genotoxicity was assessed using the Comet assay technique.ResultsThere was no significant difference between both groups regarding age and the mean duration of work was 18.94 ± 4.88 for exposed workers. The average level of noise was 95–105 dB (A). The exposed workers’ mean hearing thresholds for the left and right ears at frequencies between 2000 and 8000 Hz were substantially greater than those of the control group (P < 0.05). In the exposed workers, there was not a marked variation between the hearing thresholds of the left and right ears (p > 0.05). The exposed workers’ percentage of DNA damage was substantially greater than that of the control group (p < 0.001). Among exposed workers, a positive correlation between DNA damage, the degree of hearing loss, and the duration of time exposed to noise was demonstrated.ConclusionThe majority of exposed workers suffered from occupational noise-induced hearing loss. A positive correlation was found between the percentage of DNA damage, duration of exposure to noise, and hearing threshold in exposed workers.

Measuring the recurring frequency of noise producing sources in intensive care units (ICUs) of a tertiary care hospital in India

ABSTRACT Multiple sources contribute to the increased level of noise in a Hospital, which is way beyond the WHO recommendation limit of 35 dBA. The intensive care units contain many sources of noise, such as aspirators, monitors, mechanical ventilators, computers, printers, air conditioning vents, intercoms, staff, and doors. These sources are controllable but are overlooked. The objective of the present study is to identify the frequency of noise-producing sources in three intensive care units-Medical ICU, Neuro ICU, and Cardiac CU which were selected based on the feedback from patients. Data were collected in three shifts and included the identification of sources of sound and their classification into four categories. A sound level meter was used to record the data. Two extremes and one centre of each ICU were marked to take consistent readings in a template on an hourly basis. The average noise levels in all the 3 ICUs in the morning shift was 72.33 dBA, the afternoon shift was 72.15 dBA, and at night was 69.65 dBA. The most recurring noise sources were identified as monitor beeps (88.62%), and verbal communications (83.86%). The median intervals of the majority of the readings were between 65.1 and 70 dBA.

Rate of chainsaw vibrations in laboratory conditions and level of chainsaw noise at different distances

The study is focused on the rate of vibrations and level of noise in the chainsaw model Stihl MS 362 which belongs in the group of the best-selling professional chainsaws in the world with a highly efficient anti-vibration system. Testing cuts to determine the rate of vibrations were made on the stems of two tree species: sessile oak (Quercus petraea (Matt.) Liebl.) and Norway spruce (Picea abies (L.) H. Karst.). The purpose of noise level measurement was to compare the influence of chainsaw noise on its operator and on the person occurring behind the zone of protection (5 and 10 metres) from the source of noise. Then a distance from the chainsaw was measured where the level of noise reached 80 dB. The measurements were performed according to ČSN EN ISO 22868:2021. At measuring the chainsaw vibrations, the rate of vibrations acting on both operator’s hands (front and rear grip) was examined. Vibrations were measured according to ČSN EN ISO 22867 (2012). It was found out that the rate of vibrations on the rear handle was in both cases of measurements higher than the rate of vibrations on the front handle. At the same time, a higher rate of vibrations was recorded in sessile oak. As to the level of noise, results of measurements indicated that at working with the chainsaw, hearing protectors have to be used at all three measured distances (close proximity, 5 m from the operator, 10 m from the operator) in order to reduce high noise level as the average noise level was higher than permissible in all measurements. The highest possible tolerable level of acoustic noise (80 dB) at which permanent damage of hearing does not happen was measured at a distance of 21 m from the working place of chainsaw operator. Keywords: chainsaw, Stihl MS 362, vibrations, noise, occupational hygiene, forestry

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.&#x0D; 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.&#x0D; Purpose. Our research goal was to test the suggested approach to health risk assessment within the boundaries of an aircraft zone.&#x0D; 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.&#x0D; 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.&#x0D; 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”).&#x0D; 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.&#x0D; We established that living for more than 15 years in an airport zone with identified noise levels could result in negative health outcomes.&#x0D; 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.

Evaluation of Daily Vehicular Traffic Flows and Noise Levels at Major Junctions in Port Harcourt Metropolis, Nigeria

This study evaluated vehicular traffic flows and associated traffic noise levels at major junctions in Port Harcourt metropolis. Traffic volume was determined using visual traffic count method. Noise level was determined using an Extech digital sound level meter. Data were statistically analyzed and noise descriptors determined. Average daily traffic flows ranged from 149 to 4224. Average daily total traffic volume was minimum at Eliozu junction and maximum Eleme junction. Traffic noise varied proportionally with traffic flow. The result showed that Average noise levels varied from 70.5dB(A) to 95.9dB(A). The result showed that L10 mean values were 89.0, 90.2 91.7, 94.7 and 97.2dB(A) for Eliozu, Choba, Runuokuta, Runuokoro and Eleme junctions respectively; L50 mean values were 80.5, 81.2, 83.8, 85.2 and 89.3dB(A) for Eliozu, Choba, Runuokuta, Runuokoro and Eleme junctions respectively; L90 mean values were 69.5, 70.1, 70.4, 72.0 and 78.2dB(A) for Choba, Eliozu, Runuokuta, Runuokoro and Eleme junctions respectively. Noise climate (NC) aggregated mean values were 18.9, 19.0, 20.7, 21.3 and 22.7 for Eliozu, Eleme, Choba, Runuokuta and Runuokoro junctions respectively; Leq aggregated mean values were 86.5, 88.3, 91.4, 93.8 and 95.3dB(A) for Eliozu, Choba, Runuokuta, Runuokoro and Eleme junctions respectively; noise pollution index (Lnp) aggregated mean values were 105.4, 109.0, 113.0, 114.3 and 116.6dB(A) for Eliozu, Choba, Runuokuta, Eleme and Runuokoro junctions respectively; traffic noise index (TNI) aggregated mean values were 115.7, 122.3, 124.2, 125.6 and 132.8dB(A) for Eliozu, Choba, Runuokuta, Eleme and Runuokoro junctions respectively. The study showed evidences of high traffic noise pollution at major junctions in Port Harcourt metropolis, which may adversely affect public health and therefore requires intervention by all stakeholgers, including decision makers.

Pengaruh Karakteristik Lalu Lintas Terhadap Kebisingan Jalan Raya

The availability of transportation facilities in urban areas strongly supports community activities and mobility from one land use to another. The increase in the number of motorized vehicles causes an increase in noise level on the highway.&#x0D; The purpose of this study was to analyze the traffic characteristics on Ahmad Yani street Kendari City, noise level, and partial effect of traffic characteristics on the noise level. The research method uses descriptive and parametric statistical approaches.&#x0D; The results showed that the average traffic volume on Ahmad Yani street was 1179 pcu/hour, with a composition of motorcycles 59%, light vehicles 37%, and heavy vehicles 4%. The average vehicle speed is 48 km/hour and average traffic density is 51 pcu/km. The highest noise level occurred in the school area of 76.1 dB, while the lowest occurred in the trading area of 70.5 dB. The average noise level on the Ahmad Yani street is 73.4 dB. The effect of vehicle volume on the noise level is 56.7%, vehicle speed on the noise level is 53.4%, and the traffic density on the noise level is 68.7%. This shows that the traffic density variable has the greatest influence on the noise intensity on the highway, followed by vehicle volume variable, and the lowest is vehicle speed variable.

Analysis of noise pollution level in and around SIDCUL area in District Haridwar (Uttarakhand) India

The primary objective of this study is to evaluate the issue of noise pollution in the vicinity of the industrial zone of Haridwar city and its correlation with the health of the people in and around the SIDCUL (State Industrial Development Corporation of Uttarakhand Limited). The study revealed that noise pollution levels were above the CPCB Standard for the sound level for industrial zones and residential zones. During the period from January to December 2018, noise levels were observed and monitored in both the industrial zone (Site-I SIDCUL) and the residential zone (Site-II Siwalik Nagar). The average noise levels varied throughout the year. At Site-I (Industrial Zone), during the daytime in July, the maximum average noise level recorded was 89.5 dB, while in April; the minimum average noise level was 81.1 dB. During nighttime, in January, the maximum average noise level reached 84.1 dB, and in May, the minimum average noise level was 76.6 dB. In Site-II Siwalik Nagar (Residential Zone), the daytime noise levels were a maximum average noise level of 61.1 dB in May and a minimum average noise level of 58.8 dB in September. During nighttime, the noise level reached a maximum average of 47.2 dB in October and a minimum average of 44.5 dB in May. Overall, the study revealed that noise levels were generally higher in both zones, except for the average nighttime noise level at Site II (residential zone), which was below the prescribed standard limit for noise.

Acoustic safety assessment of palm oil mill workers

Mechanization of work processes in agro-based industries through the employment of improved tools and/or equipment powered by either fuel or diesel engines reduce tedium and drudgery on the workers as well as improve the overall productivity and production. However, it also leads to health threat to the workers through environmental noise pollution. This study assessed the occupational noise exposure of workers in three different palm oil mills. The noise level was measured using a noise metering device (model 1352) and noise descriptors (L10, L50, L90, Lav, LAeq, Total Sound Pressure Level (Tspl), DOSE (%) and TWA). The occupational health effects of noise exposure were deduced using a semistructured questionnaire. The noise exposure was assessed during the palm nut digestion, and nut and pulp separation job operations as the noise emanates from the diesel-powered engine, palm nut digester and nut and pulp separator. The average noise levels obtained from the palm oil mills during palm nut digestion, 99.36 (SD = 4.16) dBA and pulp separation, 98.18 (SD = 3.07) dBA, exceeded the recommended 85 dBA for an 8-hour exposure period permissible noise exposure limit standard by the NIOSH. The independent t-tests for noise level between off-working and working periods disclosed p &lt; 0.05 – significant noise exposure. The self-reported effect of the noise exposure level on the workers was interference with communication - 100%, tinnitus - 70%, ringing sensation - 76.75%, and noise stress - 73.30% of the workers. This research will inform the operators of the need for appropriate personal protective equipment usage and equip Government regulatory agencies to make appropriate regulations in order to protect oil mill workers.

Smartphone applications for measuring noise in the intensive care unit: A feasibility study

PurposeThis study aims to explore the suitability of using smartphone applications with low-cost external microphones in measuring noise levels in intensive care units. MethodsFour apps and two external microphones were tested in a laboratory by generating test signals at five noise levels. The average noise levels were measured using the apps and a professional device (i.e. a sound level meter). A field test was performed in an intensive care unit with two apps and one microphone. Noise levels were measured in terms of average and maximum noise levels according to the World Health Organisation's guidance. All the measurements in both tests were conducted after acoustic calibration using a sound calibrator. ResultsOverall, apps with low-cost external microphones produced reliable results of averaged noise levels in both the laboratory and field settings. The differences between the apps and the sound level meter were within ±2 dB. In the field test, the best combination of app and microphone showed negligible difference (< 2 dB) compared to the sound level meter in terms of the average noise level. However, the maximum noise level measured by the apps exhibited significant differences from those measured by the sound level meter, ranging from −0.9 dB to −4.7 dB. ConclusionSmartphone apps and low-cost external microphones can be used reliably to measure the average noise level in the intensive care unit after acoustic calibration. However, professional equipment is still necessary for accurate measurement of the maximum noise level.