Hearing Protection With Integrated In-Ear Dosimetry: A Noise Dose Study

2012 ◽  
Author(s):  
Melissa A. Theis ◽  
Hilary L. Gallagher ◽  
Richard L. McKinley ◽  
Valerie S. Bjorn
Keyword(s):  
Noise Exposure ◽  
National Standards ◽  
Hearing Protection ◽  
Octave Band ◽  
Noise Levels ◽  
Exposure Limits ◽  
Group Data ◽  
Dose Study ◽  
Hearing Protector ◽  
Naval Air Systems Command

Military personnel working in high noise environments can be exposed to continuous noise levels up to 150 dB. United States (US) Department of Defense (DoD) Hearing Conservation Programs (HCPs) [1–3] set safe noise exposure limits to reduce the risk for noise induced hearing loss. These daily noise exposure limits were based on ambient noise levels and the duration of time spent in that noise environment. Current dosimeters, worn on the lapel of personnel and at least one system worn under a hearing protector, were designed to measure noise levels and calculate noise dose, but do not provide a validated measure of noise dose external to or under a hearing protector. Noise dose under hearing protectors can be estimated by subtracting the real ear attenuation (REAT) data, collected in accordance with the American National Standards Institute (ANSI) S12.6 [4], at each octave band from the ambient octave band noise. This procedure gives accurate results for group data, but does not account for individual variations in effective attenuation. To address this issue, the US Naval Air Systems Command (NAVAIR) led the development of ship suitable in-ear dosimetry integrated into a hearing protector, and co-sponsored an effort executed by the Air Force Research Laboratory (AFRL) to calibrate in-ear noise dose readings. This was accomplished by conducting human noise exposure experiments, with and without hearing protection, which calculated noise dose from temporary threshold shifts (TTS) in hearing. Ten subjects participated in the study. Noise levels were 91, 94, and 97 dB for up to 2 hrs, 1 hr, and 30 minutes respectively. These exposure levels were well within US DoD safe noise exposure guidelines (DoD HCP) [1–3]. Data will be presented describing the open and occluded (protected) ear TTS response to noise dose achieved by subjects in the experiment. Preliminary findings indicate that human subject data is extremely important in developing and validating calibration factors for any type of noise dosimeter but is especially important for in-ear dosimetry. Results from this study demonstrated that the REAT noise dose estimations and the in-ear dosimetry earplugs consistently overestimated the effective noise dose received by subjects. However, more than 10 subjects are required to improve the confidence level of the estimated calibration factor.

Blow-Down Valve Noise and Interactions With Downstream Orifice Plates

2003 ◽  
Author(s):  
Denis G. Karczub ◽  
Fred W. Catron ◽  
Allen C. Fagerlund
Keyword(s):  
Noise Exposure ◽  
Control Valve ◽  
Low Noise ◽  
Noise Levels ◽  
Exposure Limits ◽  
Blow Down ◽  
Gas Processing ◽  
The Impact ◽  
Acoustic Fatigue ◽  
Infrequent Event

In a blow-down situation as might occur at a natural gas processing facility, noise levels are very high and significantly exceed the noise levels one would normally associate with a control valve. As the blow-down operation is an infrequent event, this may be permissible but requires consideration of the duration of these high noise levels to ensure that occupational noise exposure limits and acoustic fatigue limits are not exceeded. Tests of noise levels due to an 8-inch control valve in a 12-inch pipeline under blow-down conditions are compared here with noise level predictions based on the IEC standard. Consideration is also given to the impact of placing an orifice plate downstream of the control valve as is often done to reduce pressure drop across the valve in the expectation that control valve noise levels will be reduced. Simple orifice plates often installed by plant operators to achieve this goal are shown to have an adverse impact, and it is shown that a multi-hole diffuser or low-noise control valve should instead be used.

scholarly journals Cochrane method for systematic review and meta-analysis of interventions to prevent occupational noise-induced hearing loss – abridged

CoDAS ◽  
2020 ◽  
Vol 32 (2) ◽  
Author(s):  
Christina Tikka ◽  
Jos Verbeek ◽  
Erik Kateman ◽  
Thais Catalani Morata ◽  
Wouter Dreschler ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Noise Exposure ◽  
Meta Analysis ◽  
Hearing Protection ◽  
Noise Levels ◽  
Loss Prevention ◽  
Engineering Controls ◽  
Protection Devices ◽  
Quality Evidence

ABSTRACT Purpose Assess the effect of non-pharmaceutical interventions at work on noise exposure or occupational hearing loss compared to no or alternative interventions. Research strategies Pubmed, Embase, Web of Science, OSHupdate, Cochrane Central and Cumulative Index to Nursing and Allied Health Literature (CINAHL) were searched. Selection criteria Randomized Controlled Trials (RCT), Controlled Before-After studies (CBA) and Interrupted Time-Series studies (ITS) evaluating engineering controls, administrative controls, personal hearing protection devices, and hearing surveillance were included. Case studies of engineering controls were collected. Data analysis Cochrane methods for systematic reviews, including meta-analysis, were followed. Results 29 studies were included. Stricter legislation can reduce noise levels by 4.5 dB(A) (very low-quality evidence). Engineering controls can immediately reduce noise (107 cases). Eleven RCTs and CBA studies (3725 participants) were evaluated through Hearing Protection Devices (HPDs). Training of earplug insertion reduces noise exposure at short term follow-up (moderate quality evidence). Earmuffs might perform better than earplugs in high noise levels but worse in low noise levels (very low-quality evidence). HPDs might reduce hearing loss at very long-term follow-up (very low-quality evidence). Seventeen studies (84028 participants) evaluated hearing loss prevention programs. Better use of HPDs might reduce hearing loss but other components not (very low-quality evidence). Conclusion Hearing loss prevention and interventions modestly reduce noise exposure and hearing loss. Better quality studies and better implementation of noise control measures and HPDs is needed.

ANSI Update

2000 ◽  
Vol 9 (1) ◽  
pp. 3-8 ◽  
Author(s):  
Tom Frank
Keyword(s):  
Ambient Noise ◽  
Historical Perspective ◽  
National Standards ◽  
Computational Method ◽  
Octave Band ◽  
Noise Levels ◽  
Test Room ◽  
Hearing Thresholds ◽  
Audiometric Test

The American National Standards Institute (ANSI) specifies maximum permissible ambient noise levels (MPANLs) allowed in an audiometric test room to ensure that hearing thresholds obtained down to 0-dB HL will not be elevated due to masking by ambient noise. MPANLs were originally specified in 1960 and have been revised in 1977, 1991, and most recently in 1999. The purpose of this report is to offer an overview by providing a historical perspective of the MPANLs recently specified by ANSI (ANSI S3.1-1999), the rationale for revising the MPANLs, the new computational method used for determining the 1999 MPANLs, the ANSI S3.1-1999 octave and one-third octave band MPANLs, and information concerning compliance with the new MPANLs.

scholarly journals Noise perception and hearing protector use in metallurgical industries

2018 ◽  
Vol 2 (1) ◽  
pp. 18-28
Author(s):  
I. C. Wictor ◽  
A. A. de P. Xavier
Keyword(s):  
Noise Exposure ◽  
Working Environment ◽  
Noise Levels ◽  
The Social ◽  
Hearing Protectors ◽  
Temporary Solution ◽  
Increasing Risk ◽  
Hearing Protector ◽  
Effective Use ◽  
Safety Procedures

Although hearing protectors are defined as a temporary solution, they are often widely employed as the only measure against noise exposure. However, it is also known that unless workers wear the hearing protector continuously, their effectiveness will be very low. In this regard, there are some surveys that show that workers do not always wear their protectors properly and consistently while exposed to noise. The purpose of this article is to present the results of an investigation about noise perception, relating with noise exposure in working environment and the hearing protectors’ use. Was consider that noise perceptions effects can support minimizing risk and improve industries safety polities. The study sample was carry out in 5 metallurgical industries and 243 workers from Parana – Brazil. The survey data was collected and analyzed by Statistical Package for the Social Sciences (SPSS). The questionnaire results showed that workers are exposed at high noise levels, in increasing risk of developing noise-induced hearing loss (NIHL). About the hearing protection use, it can be evaluated that the use is more effective in companies with a higher level of noise exposure. The perception of risk plays a fundamental role, which predicts the use of hearing protectors; therefore, the perception of the work environment, regarding the lower or higher risk, can be directly linked to the use of hearing protectors. The companies with more rigorous safety procedures also indicate a greater report of effective use of hearing protectors.

scholarly journals Workers of the hospital maintenance sector: protection, hearing symptoms and noise exposure

Revista CEFAC ◽  
2018 ◽  
Vol 20 (4) ◽  
pp. 503-514
Author(s):  
Flávia Elisa Antunes Lemes de Oliveira Ramos ◽  
Adriana Bender Moreira de Lacerda ◽  
Evelyn Joice Albizu
Keyword(s):  
Noise Level ◽  
Noise Exposure ◽  
Signs And Symptoms ◽  
Hearing Protection ◽  
Speech Comprehension ◽  
Cross Sectional ◽  
Daily Work ◽  
Hearing Protectors ◽  
Maintenance Service ◽  
Hearing Protector

ABSTRACT Purpose: to investigate the use of hearing protection and symptoms in hospital maintenance workers and evaluate the noise level of the machines. Methods: a cross-sectional quantitative study held with workers from a public hospital maintenance service. A questionnaire related to personal, clinical and occupational history was used. Measurement of the noise level of the machines in the sector was carried out using a sound pressure level meter. Results: 57 male workers participated, mean age of 43.28 years, among the workers, carpentry prevailed (10.53%), length of time at the job averaged 8.9 years and 9.3 daily work hours; 45.76% did not know what could be done to reduce maintenance noise; 59.65% wore hearing protectors at work, ear plug model (47.37%), and 82.45% thought that the noise was reduced when they wore the hearing protector correctly. Auditory and non-auditory signs and symptoms were denied by most workers. Noise perception in the maintenance service was medium (53%) and high (44%), evidenced noise levels of 62.0 to 101dB (A). Conclusion: the hearing protector was worn by 59.7% of the workers, the plug model was the most used (47.4%) and 75.8% reported that occupational noise decreased with the use of hearing protectors. Most workers use hearing protection and have no hearing symptoms. However, the presence of symptoms such as otalgia (8.8%), otorrhea (5.3%), dizziness (14.0%), tinnitus (17.5%) and difficulty in speech comprehension (7, 0%) should be pointed out. Noise assessment showed high levels from some maintenance machinery, representing a risk for hearing. The sectors of the woodwork and metalwork were the noisiest.

Damage Risk: An Evaluation of the Effects of Exposure to 85 versus 90 dBA of Noise

1976 ◽  
Vol 19 (2) ◽  
pp. 216-224 ◽  
Author(s):  
James T. Yates ◽  
Jerry D. Ramsey ◽  
Jay W. Holland
Keyword(s):  
White Noise ◽  
Statistical Difference ◽  
Noise Exposure ◽  
Threshold Shift ◽  
Temporary Threshold Shift ◽  
Noise Levels ◽  
Potential Damage ◽  
Full Day ◽  
Damage Risk

The purpose of this study was to compare the damage risk of 85 and 90 dBA of white noise for equivalent full-day exposures. The damage risk of the two noise levels was determined by comparing the temporary threshold shift (TTS) of 12 subjects exposed to either 85 or 90 dBA of white noise for equivalent half- and full-day exposures. TTS was determined by comparing the pre- and postexposure binaural audiograms of each subject at 1, 2, 3, 4, 6, and 8 kHz. It was concluded that the potential damage risk, that is, hazardous effect, of 90 dBA is greater than 85 dBA of noise for equivalent full-day exposures. The statistical difference between the overall effects of equivalent exposures to 85 dBA as compared to 90 dBA of noise could not be traced to any one frequency. The damage risk of a full-day exposure to 85 dBA is equivalent to that of a half-day exposure to 90 dBA of noise. Within the limits of this study, TTS t was as effective as TTS 2 for estimating the damage risk of noise exposure.

Aircraft Noise Levels, Annoyance and General Health of Residents of Communities contiguous to a Major Airport in Lagos State

2020 ◽  
Vol 8 (4) ◽  
pp. 47-59
Author(s):  
Iheanyichukwu M. Elechi
Keyword(s):  
Health Status ◽  
General Health ◽  
Noise Exposure ◽  
Aircraft Noise ◽  
Poor Health ◽  
Noise Levels ◽  
General Health Status ◽  
Lagos State ◽  
Distant Location ◽  
Self Reported Health Status

The purpose of this study was to investigate the relationship between the aircraft noise exposure, annoyance reactions and health status of the residents living within the vicinity of the Murtala Muhammed International Airport (MMA) in Lagos state, Nigeria. Aircraft noise monitoring was conducted in five locations within the vicinity (0-5Km) of MMA, and a sixth distant location (14km away). Levels of aircraft noise for all five locations within the vicinity of the airport exceeded the EPA Victoria threshold of 75 dB LAmax for the residential area (outdoor). A survey on annoyance induced by aircraft noise exposure and general health status was conducted on 450 local residents in the study locations using the International Commission on Biological Effect of Noise question and a single question that has been applied in Dutch national health care surveys since 1983 on self-reported general health status respectively. Percentage of residents within the vicinity of MMA that were highly annoyed (%HA) exceeded 15% guideline limit stipulated by Federal Interagency Committee on Urban Noise while 14.5% reported poor health status. There was a significant association between the annoyance reactions and aircraft noise levels in the study locations while the association between self-reported health status and aircraft noise levels was not significant. Taken together, the residents within the vicinity of the airport are exposed to aircraft noise levels above permissible limit which may be associated with high annoyance reaction but may not be associated with poor health rating. Evidence-based aircraft noise related policies by government are advocated.

Noise Exposure and Hearing Disorders

2017 ◽  
Author(s):  
David C. Byrne ◽  
Thais C. Morata
Keyword(s):  
Hearing Loss ◽  
Noise Exposure ◽  
Hearing Protection ◽  
Noise Induced Hearing Loss ◽  
Hearing Disorders ◽  
Industrial Noise ◽  
Significant Impairment ◽  
Protection Devices ◽  
The Impact ◽  
Occupational Hearing Loss

Exposure to industrial noise and the resulting effect of occupational hearing loss is a common problem in nearly all industries. This chapter describes industrial noise exposure, its assessment, and hearing disorders that result from overexposure to noise. Beginning with the properties of sound, noise-induced hearing loss and other effects of noise exposure are discussed. The impact of hearing disorders and the influence of other factors on hearing loss are described. Typically, noise-induced hearing loss develops slowly, and usually goes unnoticed until a significant impairment has occurred. Fortunately, occupational hearing loss is nearly always preventable. Therefore, this chapter gives particular attention to recommendations for measures to prevent occupational hearing loss such as engineering noise controls and hearing protection devices.

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