Recorded Noise Levels Research Articles

Multidimensional analysis of road traffic noise and probable public health hazards in Barisal city corporation, Bangladesh

Noise pollution is a major challenge in urban contexts all around the world. The study was designed to assess road traffic noise pollution with possible health effects on those living in the study region. The IDW spatial interpolation approach and an ArcGIS-based evaluation were used to map the recorded noise levels in the research region. The noise descriptors including Noise Climate (NC), Traffic Noise Index (TNI), Equivalent Noise Level (Leq), and Noise Pollution Level (NPL) were computed. The required information has been collected through a questionnaire survey and previously published documents. The study reveals that the current noise level is higher than the recommended national threshold at every location. According to the study, the Nathullabad region had the highest level of noise pollution (86.5 dBA), while the Kaunia Abasik area had the lowest level (67.8 dBA). Study findings also show that in the area context, the highest levels of noise pollution are found in commercial areas (82 dBA), followed by industrial areas (80.4 dBA),mixed areas (81.3 dBA), and residential areas (72.7 dBA). The lowest level is found in sensitive areas (72.5 dBA). Statistical analyses, including one-way ANOVA, Tukey HSD post-hoc and LSD post-hoc test results, showed that there was no statistically significant difference (p > 0.05) between the noise pollution levels (NPL) in the morning, noon, and evening shifts. The results showed that 32 % of respondents stated they felt disturbed while working, and 27% of respondents said it was somewhat sensitive for them. As the last step in minimizing noise pollution in the research area, 37 % of respondents reported enforcing the regulations, 31% suggested making hydraulic horns illegally, and 21 % suggested raising public awareness. This study may contribute to academic knowledge and assist decision-makers of government officials in formulating appropriate local strategies to deal with this grave environmental problem.

Comparison of Two Clinical Devices for the Measurement of Distortion Product Otoacoustic Emissions in Normal-Hearing Adults.

Otoacoustic emissions (OAEs) are low-intensity sounds generated by the cochlea and associated with the function of the outer hair cells. Since OAE measurements do not require active participation of a listener, OAEs are considered an objective measure of cochlear function. While distortion-product OAEs (DPOAEs) are commonly used in clinical practice, limited information is available on the performance of various clinical devices. This study compared two commercial clinical devices, Titan and Eclipse from Interacoustics, and collected normative data for DPOAEs in people with normal hearing. The data collection and analysis were focused on signal and noise amplitudes as well as signal-to-noise ratios (SNRs). Sixty-three participants with normal hearing (age 23.2±2.0 years) were included in the study. DPOAEs were measured at 31 frequencies ranging from 500 to 10,000 Hz. DPOAE amplitude differed across frequencies. Additionally, a high number of unreliable responses were observed at the edge frequencies (<828 Hz and >6,072 Hz). There were no significant differences between the two devices in terms of DPOAE amplitudes, but the recorded-noise levels (amplitude) differed significantly. SNRs of the recorded OAEs were frequency dependent (higher frequencies showed larger SNRs), and significant differences in terms of SNR were found between the two devices. Despite the above-mentioned differences, the OAEs recorded with both devices met the pass criteria for the SNR (≥6 dB) consistently across frequencies, and thus the differences do not compromise the test outcomes. The frequency dependence of the OAE amplitudes and the corresponding SNRs may be relevant for clinical practice.

Traffic noise pollution level at selected cities in Kelantan

In densely populated areas where the communities strive, noise pollution has become a critically alarming problem and must be addressed accordingly. The World Health Organization also recognizes it as a concerning public health issue in the urban areas. More often, the effects of noise towards the residents living in the vicinity areas can include the worsening of life quality and result in physiological effects, among others. We hypothesize that the increasing traffic results in higher noise pollution levels. The aim of this study was to quantify traffic noise pollution using noise pollution level (NPL) and traffic noise index (TNI) at selected cities in Kelantan, namely Tanah Merah and Pasir Mas. A sound level meter (TENMARS TM102) was used to record the noise level, and the traffic volumes were determined by using tally counts. The noises were measured during four different peak hours from 08:00 to 22:00. The recorded noise levels were compared with the Department of Environment (DOE) recommended limit of 60 dB(A) during daytime. The traffic noise pollution level was confirmed to be higher when the traffic volume counts increased. The results suggest proper mitigation measures such as enforcing zoning regulations and promoting public awareness campaigns were needed to reduce the noise pollution level.

Czech society and drones: experience, norms, and concerns

Understanding societal acceptance of drones is key to their operational incorporation to flight space. For this reason, this study measures experience, norms, and concerns related to drone operation on a quota representative sample of the Czech public and provides an overview of the situation. It finds out that a majority of Czechs already has some level of personal experience with drones and that Czechs are quite confident about high quality of drones’ performance in regard to manoeuvrability, video recording, or low noise levels. Despite these, more legislative regulations and their stronger enforcement are favoured by the majority. Public acceptance of a particular type of flight operations is then highly dependent on the operators’ institutional background. Operations by police and firefighters are supported significantly more. Finally, it is shown that privacy is the driving concern compared to safety or noise in the Czech Republic. Given these, it seems reasonable to focus further communication with the public about this issue, particularly on the introduction of technological capabilities, societal effects of drone operation, and the current legislative framework related to privacy rights and new technologies rather than on promoting drone operation safety.

Evaluation of Traffic Noise Level in Residential Areas Along Jalan Kluang - Case Study in Sri Gading, Batu Pahat, Johor

Noise, recognized as an adverse factor affecting human health and overall well-being, poses a significant public health concern. This study focuses on evaluating the traffic noise levels in residential areas along Jalan Kluang. Measurements were conducted in four selected residential areas, namely Taman Sri Saga, Taman Cempaka Putih, Kampung Kluang, and Taman Bahagia Baru, during morning (7.30 am - 9.30 am) and evening (4.00 pm - 6.00 pm) peak hours on weekdays. The results indicated that certain locations exceeded the noise limit that set by the Department of Environment (DOE). Kampung Kluang exhibited LAeq values of 71.10 dBA and 71.48 dBA during the morning and evening peak hours, respectively, surpassing the DOE noise limit. Taman Cempaka Putih also recorded noise levels, with LAeq values of 69.40 dBA and 66.46 dBA during the morning and evening peak hours, respectively. In contrast, Taman Sri Saga and Taman Bahagia Baru demonstrated LAeq values still below the DOE limit during both peak hours. Taman Sri Saga recorded LAeq values of 55.63 dBA and 57.78 dBA, while Taman Bahagia Baru recorded LAeq values of 57.58 dBA and 59.65 dBA during the morning and evening peak hours, respectively. Therefore, it is crucial to address the excessive noise levels in the affected residential areas to mitigate the detrimental effects and ensure a healthier living environment for the affected residents in those areas.

Self-Reported Health Effects and Risk Factors Associated with Noise Exposure among Auto-Mechanic Workers in Abeokuta Town, Nigeria

This study was conducted to determine the noise exposure level and the association between self-reported health effects and risk factors among workers in auto mechanic workshops in Abeokuta town, Nigeria. Noise levels were measured at selected auto mechanic sites. A cross-sectional study was also conducted among fifty workers using a wellstructured questionnaire across the sampling sites. The recorded noise level in the morning and afternoon ranged between 61.3 - 75.8 dB and 70.4 and 86.4dB respectively. The noise values in the afternoon were significantly higher than the morning noise levels (t = -2.231; p = 0.030). The noise levels were above the WHO permissible limits in all the sampling locations. The overall occurrence of self-reported health effects were hearing loss (32%), annoyance (62%), irritation (72%), insomnia (16%), ringing in ears (44%), fatigue (44%), and high blood pressure (18%). The reported noise-induced health effects were associated with the age of the workers, duration of noise exposure and perceived noise sources in the study area. In the binomial regression model, exposure to occupational noise for 8 – 12 hours daily was an independent determinant risk factor of hearing loss (OR = 2.27, 95% Cl, 1.21-24.88) and fatigue (OR = 5.00, 95% Cl, 1.16-21.50). The implementation of correct wearing of earplugs among workers and the creation of awareness on noise-induced health effects to reduce noise exposure in the working environment would help in protecting exposed workers in the study area.

Assessment of traffic noise pollution at residential and school areas in Jeli, Kelantan

The development of roads interconnects communities and has become important for economic and social development. Higher traffic noise level is often reflected by the increase in the number of vehicles. This paper discussed the relationship between noise level and vehicle density in the study area. The aim of this study was to assess the traffic noise pollution occurring in the residential and school areas in Jeli, Kelantan. The traffic noise measurement was collected using a sound level meter for three consecutive months (July, August and September 2023). The traffic volume was recorded by traffic surveying. The assessments were carried out from 8.00 a.m – 8.00 p.m. The recorded noise levels were compared with the permissible limit (Malaysian noise limit). The highest noise level recorded was 85.9 dBA, well over the permissible limit of 60 dBA by DOE. This was due to the high number of vehicles passing by the road in the study area and the highest number of vehicles recorded was 4976 during sampling time in July at Kg Gemang. Overall, the traffic noise assessments for this study were beyond the standard limit set by DOE during daytime. This considerably high noise could lead to other health effects for the residents.

Remote Sensing based Noise Level Assessment: A Case Study of Coimbatore City, India

Major cause of noise pollution is the improper design of city with mixed zones. Normally a city is defined by four major zones namely: Commercial, Industrial, Residential and Silence Zones respectively. The noise pollution occurs due to traffic and transport and when industrial zones mix up with residential or silence zones. So, noise pollution can be controlled efficiently when construction or progress of buildings are within their respective zones. Study area, Coimbatore is the largest non-metro city in India reported to face frequent noise pollution issues. It has many industries (Textile, Foundry, pumps etc), within the city and many of the industries are clubbed together with other zones as mixed. Noise monitoring is carried out in the city by dividing the city into five major regions. The important places of each region were monitored during regular time intervals (peak hours). The modelling of the localities predicts the Noise impacts in the form of map using the ArcGIS software. The summation of recorded noise levels gives the prevailing noise in the place, and helps to identify the risk areas. The results demarcate the considered regions into regions where noise level are within limits and regions where noise exceeds. The control methods are suggested to be implemented in the affected areas.

Noise and Spatial Configuration in Biskra, Algeria—A Space Syntax Approach to Understand the Built Environment for Visually Impaired People

This contribution investigates the correlation between street noise levels and the spatial configuration of the street network in four different types of neighbourhoods in the Algerian city of Biskra. Space syntax methods are used to analyse spatial relationships, where accessibility, intelligibility, and legibility of urban spaces can be evaluated. The degree of spatial integration is used as an accessibility indicator and is correlated with recorded noise level data at 154 points from the selected neighbourhoods. As the results show, there are strong correlations between spatial integration and recorded sound pressures on streets and roads in colonial and unplanned neighbourhoods. The reason is that these types of neighbourhoods have a street network with high correlations between street connectivity and global spatial integration. There are weak correlations between connectivity and global spatial integration throughout the modern planned neighbourhood, which again affects the correlation between noise and space. The experiment shows that space syntax methods have the potential to predict degrees of accessibility and orientability for people with visual impairments in urban planning.

On the Detection Capabilities of Underwater Distributed Acoustic Sensing

AbstractThe novel technique of distributed acoustic sensing (DAS) holds great potential for underwater seismology by transforming standard telecommunication cables, such as those currently traversing various regions of the world’s oceans, into dense arrays of seismo‐acoustic sensors. To harness these measurements for seismic monitoring, the ability to record transient ground deformations is investigated by analyzing ambient noise, earthquakes, and their associated phase velocities, on DAS records from three dark fibers in the Mediterranean Sea. Recording quality varies dramatically along the fibers and is strongly correlated with the bathymetry and the apparent phase velocities of recorded waves. Apparent velocities are determined for several well‐recorded earthquakes and used to convert DAS S‐wave strain spectra to ground motion spectra. Excellent agreement is found between the spectra of nearby underwater and on‐land seismometers and DAS converted spectra, when the latter are corrected for site effects. Apparent velocities greatly affect the ability to detect seismic deformations: for the same ground motions, slower waves induce higher strains and thus are more favorably detected than fast waves. The effect of apparent velocity on the ability to detect seismic phases, quantified by expected signal‐to‐noise ratios, is investigated by comparing signal amplitudes predicted by an earthquake model to recorded noise levels. DAS detection capabilities on underwater fibers are found to be similar to those of nearby broadband sensors, and superior to those of on‐land fiber segments, owing to lower velocities at the ocean‐bottom. The results demonstrate the great potential of underwater DAS for seismic monitoring and earthquake early warning.

Noise vulnerability of stone mining and crushing in Dwarka river basin of Eastern India

The present paper has intended to explore the noise level and vulnerability to noise produced in the stone mining and crushing area and the surroundings in the heavily stressed stone mining and crushing area of Middle catchment of Dwarka river basin of Eastern India. Field-based noise recording has been done at different times in every recorded days. Fuzzy logic-based weighting and integration of eight parameters have been done in four selected cluster for noise susceptibility mapping. For exploring noise annoyance odd and risk ratio have been computed for different communities. From the recorded noise level in stone crushing clusters, it is found that the noise level is > 85 dBA from 6 a.m. to 4 p.m. when the stone crushers are running on and it is above the ambient noise threshold defined by Central Pollution Control Board in 2000. Maximum noise level is recorded as 112.41 dBA which may cause deafness. Noise intensity gradually decreases from crushing centre towards outside and it prevails up to 500–650 m away from the crushing unit. Noise vulnerable areas constructed based on eight noise level addressing and noise effect indicating parameters using fuzzy logic revealed that about 10.46–27.98% areas fall under very high to high noise vulnerable zones. Therefore, the labourers and the peoples who are living at close proximity of crusher units are highly prone to noise pollution along with stone dust pollution. The effect of noise is highly age and sex sensitive due to their differences in physical strength. These findings could effectively be used for saving the exposed communities from noise vulnerability.

Effects of COVID-19 outbreak on the sound environment of the city of Milan, Italy

Abstract In this paper, we present the results of the noise monitoring in the urban area of Milan, Italy, associated with COVID-19 outbreak. In order to limit the diffusion of the pandemic, Italy adopted growing levels of restrictive measures, which ended with a 41-day lockdown from March 23 to May 3 2020. This action created a new kind of environment including a remarkable reduction of air, water and soil pollutants, together with a partial recovery of the ecosystems otherwise compromised. The presence of a permanent noise monitoring system made of 24 sensors installed in the city of Milan, allowed capturing the changes in the urban sound environment in a pre, during and post-lockdown period (months from February to June 2020). The comparison of the noise levels in terms of both absolute noise levels (Lden) and hourly noise profiles (median over lockdown period) with the same period of 2019, showed a dramatic reduction of the noise levels of approximately 6 dB. Splitting the contribution of all-non-traffic noises or anomalous noise events (ANE) from the recorded noise levels, we observe a greater contribution of the latter during the lockdown period. The use of DYNAMAP noise prediction system over an extended urban area allowed the evaluation of the population exposure to noise, estimating an increase of 14.9% and 16.4% of the exposed population to noises with Lden below 53 dB(A) and Lnight below 45 dB(A) with respect to 2019.

Determination of the level of condensate by recording the noise level in the respiratory circuit of mechanical ventilation devices

Abstract. The method of determining the accumulation of condensate by registering the noise level in the respiratory circuit of ventilators is substantiated. According to the proposed method, the condition and performance of the apparatus is monitored during artificial lung ventilation and oxygen therapy. With hardware ventilation, an increasing turbulent flow of a water or gas stream is formed in the respiratory circuit, accompanied by an increase in the noise effect and vibration. An increase in the level of acoustic noise from fluctuations in the accumulation of condensate in gaseous media was recorded by an instrument for objective measurement of sound level a sound level meter. Indicators of noise effects reached a higher level on the wet circuit (the presence of condensation droplets or accumulations of mucus) of the liquid compared with the indicators obtained on the dry breathing circuit. The difference in recorded noise levels reached 10 dB, and increased from 37,73 to 47,36 dB. Areas of the respiratory circuit with the greatest degree of narrowing of the lumen and critical accumulations of water condensate and mucus are a source of turbulence in the air flow and increased noise. In conditions of prolonged artificial ventilation of the lungs, the rate of humidified air-gas flow is constantly changing, especially with hardware modeling of the phases of inspiration and expiration, and an increase in temperature in the humidifier chamber. The proposed technique is designed to identify critical levels of water condensate in the apparatus breathing circuits by recording the intensity of the increase in noise level and choosing the rational mode of operation of medical equipment. Data on the emerging critical situation are displayed on the sound level meter screen and inform medical personnel about the need to rehabilitate the circuit of the artificial lung ventilation apparatus. The primary field of application is resuscitation and intensive care units, medical transport teams during in-hospital or inter-hospital transportation, and surgical operating rooms during inhalation anesthesia.

Too noisy to sleep safely?-An observational study of noise levels and distractions during critical phases of pediatric anesthesia.

Noise and distraction are recognized as contributing factors in critical incidents associated with surgery and anesthesia. In addition, excessive noise exposure can have negative effects on patients and staff members in these environments. We aimed to quantify noise exposure of the anesthesiology team and patients in pediatric operating theaters, comparing them to adult studies, internationally recognized standards, and identifying factors contributing to noise and/or distraction. We measured noise levels during three phases of anesthesia (pre-induction, induction, and postinduction/maintenance) and recorded additional environmental sources of distraction and noise. We included 49 theater cases. The median and interquartile range (IQR) of mean noise levels during pre-induction, induction, and maintenance were 61 (59.7-63.5), 61.9 (60.6-63.3), and 61.6 (60.4-63.7) dB, respectively, while the median (IQR) of maximal noise levels was 81.4 (77.3-86.8), 83.7 (78.5-87.4), and 86.3 (84.6-90.4), respectively. There was an average of 8.3 people present in the room during induction. In 23 cases, there were additional unnecessary conversations occurring within the room at induction. We noted the maintenance phase was the noisiest phase of anesthesia. We recorded frequent potential sources of distraction during pre-induction and induction, though no significant correlations between these distractions and recorded noise levels. We documented noise levels well above recommended levels during all phases of pediatric anesthesia. We highlighted factors with potential to contribute to noise and distraction but found no statistically significant correlation with noise levels.

Spatial characterization of noise levels at the Federal University of Agriculture, Abeokuta, Nigeria

The study investigated the spatial variability in the distribution of noise pollution in Federal University of Agriculture, Abeokuta. Measurements of noise were taken from 10 locations on campus namely; the academic environment including the University library and college lecture auditoria, the residential areas comprising the Student hostels and Vice-chancellor’s lodge as well as other populated areas like the car park and student union building. The noise measurement was done in the morning and evenings of Mondays, Wednesdays and Saturdays over a period of 3 weeks in July 2019. The noise measurement was done with the aid of Smart Sensor Digital Sound Level meter (Model: AR824). The sampling points were geo-located using a hand-held receiver for Global Positioning Systems (GPS). Questionnaires were administered to members of the University community (staff and students) to determine their respective perception of campus noise on academic activities. Data (noise and survey) were subjected to statistical analysis. Spatial analysis of the noise levels includes surface interpolation (Krigging) to determine the spatial pattern of noise across the campus, particularly, the most tranquil and most chaotic locations. The results show noise pollution levels reaching 74.3 (db) and 73.0 (db) during weekdays at some locations on campus. The noise emission level at some locations within the University exceeded the World Health Organization and Federal Ministry of Environment of Nigeria’s permissible level of 55 db for residential areas. Generally, it was observed that the ambient noise from heavy duty generating with the student chattering put noise level above 35(db) to 55(db) recommended for educational institutions. It can be inferred from statistical analyses and spatial interpolations of recorded noise levels, that noise levels of many areas in FUNAAB exceed the recommended 40 db required for an institution of higher learning. The study however finds that staff and students have adjusted to the noise on campus. Lecturers have resorted to the use of public address systems in large classes while students go to serene locations for better assimilation when studying. The study recommends reduction of point-source noises such as replacing the diesel generators with solar power. Signage should be displayed at sensitive areas such as library to reduce unnecessary noise.

Associations between stressors and difficulty sleeping in critically ill patients admitted to the intensive care unit: a cohort study

BackgroundPatients admitted to the intensive care unit (ICU) experience sleep disruption caused by a variety of conditions, such as staff activities, alarms on monitors, and overall noise. In this study, we explored the relationship between noise and other factors associated with poor sleep quality in patients.MethodsThis was a prospective cohort study. We used the Richards–Campbell Sleep Questionnaire to explore sleep quality in a sample of patients admitted to the ICU of a private hospital. We measured the noise levels within each ICU three times a day. After each night during their ICU stay, patients were asked to complete a survey about sleep disturbances. These disturbances were classified as biological (such as anxiety or pain) and environmental factors (such as lighting and ICU noise).ResultsWe interviewed 71 patients; 62% were men (mean age 54.46 years) and the mean length of stay was 8 days. Biological factors affected 36% and environmental factors affected 20% of the patients. The most common biological factor was anxiety symptoms, which affected 28% of the patients, and the most common environmental factor was noise, which affected 32.4%. The overall mean recorded noise level was 62.45 dB. Based on the patients’ responses, the environmental factors had a larger effect on patients’ sleep quality than biological factors. Patients who stayed more than 5 days reported less sleep disturbance. Patients younger than 55 years were more affected by environmental and biological factors than were those older than 55 years.ConclusionsPatient quality of sleep in the ICU is associated with environmental factors such as noise and artificial lighting, as well as biological factors related to anxiety and pain. The noise level in the ICU is twice that recommended by international guides. Given the stronger influence of environmental factors, the use of earplugs or sleeping masks is recommended. The longer the hospital stay, the less these factors seem to affect patients’ sleep quality.

MONITORING NOISE LEVELS ALONG THE GREATER CAIRO URBAN REGION RING ROAD IN EGYPT

In this study, the noise levels were monitored at Cornish EL Maadi (A), Gezirat El Dahab (B) and Al-Marioteya (C). The data revealed that the noise levels at Corniche El Maadi Street (A) and Al-Marioteya (C) (all day) as well as at Gezirat El Dahab (B) (evening) exceeded the set noise regulations in Egypt. Overall, it was the buses, private cars + taxis, mini vans and mini truck that made the main bulk of traffic passing through the ring road on weekdays. However, the study revealed that the main category of vehicles contributing towards the recorded noise levels was the miscellaneous type. This means of transportation were slow and proceeded along the right lane of the road and thus had a more measurable impact upon the recorded noise levels at the 3 monitored locations. However, the contribution from vans and mini-trucks towards the noise levels recorded was significant at Gezirat El Dahab and Al-Marioteya during Monday and Friday, respectively. Nonetheless, such contribution was not witnessed for Corniche El Maadi Street, where the miscellaneous category was a predominant noise contributing factor during both Monday and Friday.

Installing Noise Activated Warning Signs in Library Quiet Spaces Does Not Appear to Reduce Actual or Perceived Noise Levels

A Review of:&#x0D; Lange, J., Miller-Nesbitt, A., &amp; Severson, S. (2016). Reducing noise in the academic library: The effectiveness of installing noise meters. Library Hi Tech, 34(1), 45-63. https://doi.org/10.1108/LHT-04-2015-0034&#x0D; Abstract&#x0D; Objective – To explore if installing noise activated warning signs (NoiseSigns) in library quiet spaces decreases perceived and actual noise levels.&#x0D; Design – Noise monitoring and user surveys (print and online).&#x0D; Setting – A large university in Canada.&#x0D; Subjects – Users of library quiet spaces where NoiseSigns have, and have not, been installed.&#x0D; Methods – NoiseSigns provide a visual cue informing those present when noise levels exceed a pre-determined level. In this study, researchers installed two NoiseSigns in quiet study spaces previously identified as having the “biggest noise issues” (p. 51), and set the devices to illuminate when noise levels exceeded 65 dB. User surveys investigated respondents’ perceived and desired noise levels via Likert scales before and after NoiseSigns were installed. Actual noise level measurements (via an iPad app) and headcounts were taken manually twice daily for 60 seconds during the same study phases. Additionally, the NoiseSigns recorded noise levels after they were installed. In order to account for variation in library usage over time, control data was also collected in other spaces, where NoiseSigns had not been installed.&#x0D; Main results – A total of 96 surveys were completed and analyzed across all study locations and time periods. One-way ANOVA tests showed there to be no significant difference in perceived noise levels after installing NoiseSigns in any of the intervention areas, in neither the short- or long-term. Respondents’ comments suggested much of the undesired noise originated from social areas adjacent to the quiet study zones or was of a type which would not set off the NoiseSigns (e.g., “people chew[ing] too loud[ly]” (p. 54)). One-way ANOVA tests also found there to be no significant difference in actual noise levels in any of the intervention areas after device installation. Data logging from the NoiseSigns themselves showed the “majority” (p. 56) of noise measurements were in the vicinity of 45-50 dB and “very rarely” (p. 56) did noise levels exceed the 65 dB threshold. Despite this, survey respondents appeared to be unhappy with noise, with mean desired noise levels being lower than those perceived.&#x0D; Conclusion – As a result of the study, the library now strives to have greater delineation between quiet and social spaces. They also seek to ensure doors between these areas are kept closed where possible. Additionally, the authors suggest libraries install noise activated warning signs in social spaces adjacent to quiet study zones in order to keep these spaces from becoming noisy enough to affect nearby quiet zones. Future research could look at the effect of different monitoring options (e.g., security guards, student self-monitoring) and various furniture arrangements on noise levels in the library.

Determinants of noise level in the neonatal intensive care unit at Castle Street Hospital for Women, Colombo, a level III tertiary care facility

Introduction: Advances in modern neonatology have improved survival of extremely premature and extremely low birth weight babies. Increased noise level is proven to be harmful to preterm babies and term ill babies in various ways. Determinants and baseline noise level should be assessed before necessary intervention. Objective: To assess the determinants of noise level at a level III neonatal intensive care unit (NICU) at the Castle Street Hospital for Women (CSHW), Sri Lanka. Method: A prospective observational study was done at NICU, CSHW, Sri Lanka. Data were collected using two NDI USB Digital sound level data loggers recorded noise level on a weighted decibel scale (dBA) every minute continuously for three weeks. Data was exported using provided software. Average noise level was analysed separately for consultant ward round (9am-12pm), nursing handing-over time (Daily 7-7.30am, 1-1.30pm and 7-7.30pm), admissions/emergencies (time taken from records) and a period supposed to be silence (Daily 1am-3am). Recommended standard ambient noise level for NICU by the American Academy of Paediatrics as well as Australasian Health Infrastructure Alliance is less than 45dB. Results: Average noise level recorded in NICU was 60 dBA which is considerably higher than recommended levels. During the consultant ward round the average noise level was 60.2 dBA. Noise levels at the morning, afternoon and evening handing-over times were 62.9, 62.7 and 60.9 dBA respectively. Noise level at supposed silent period (Daily 1am-3am) was 56.8 dBA. During admissions or emergencies which required ventilation (CPAP/conventional), the average noise level was as high as 65.8 dBA. Conclusions: Noise levels recorded in the NICU at the CSHW, Sri Lanka in all circumstances were higher than the recommended noise levels. Main contributions were machine alarms and conversations. Sri Lanka Journal of Child Health, 2019; 48(4): 312-315

Effectiveness of a visual noise warning system on noise levels in a surgical ICU: A quality improvement programme.

The effects of noise are harmful to patients in the ICU environment, and the latter are particularly noisy places. High noise levels seem to be a factor in sleep disturbance, which can, in turn, result in increased morbidity. High noise levels are a recognised problem in ICUs worldwide. The goal was to estimate the effect of a visual noise-warning system on noise levels in a surgical ICU before and after its implementation. A quality improvement initiative. A 12-bedded surgical ICU in a tertiary care university hospital. A total of 148 adult nonintubated and nonsedated patients completed the study, during a 6-week period. Noise levels were continuously recorded using a Type II sound level meter for 6 weeks. The study was divided into three phases. The first 2 weeks, baseline noise levels were measured (phase I). In week 3 of the study, a visual noise warning system (SoundEar II) that changed colour depending on noise levels within the ICU was installed and implemented (phase II). The alarm system was set to light up green at levels below 55 dBA, orange at levels between 55 and 60 dBA and red at levels above 60 dBA. The device was switched off at the beginning of week 5 and the sound level meter continued recording noise levels for another 2 weeks (phase III). Mean night-time noise level was 55.98 dBA in the preintervention phase, 54.14 dB during the intervention, and 54.98 dBA in the postintervention phase. Mean noise level was reduced statistically significantly by 1.35 dBA, and there was a sustained reduction of 0.86 dBA from the baseline noise level 2 weeks after SoundEar II was switched off. Visual noise warning systems can be effective in achieving a reduction in noise levels in critical care units.