scholarly journals The Impact of Different Permissible Exposure Limits on Hearing Threshold Levels Beyond 25 dBA

2014 ◽  
Vol 16 (10) ◽  
Author(s):  
Balachandar S. Sayapathi ◽  
Anselm Ting Su ◽  
David Koh
Keyword(s):  
Hearing Threshold ◽  
Exposure Limits ◽  
Threshold Levels ◽  
Permissible Exposure Limits ◽  
The Impact

Noise-Induced Hearing Loss in Professional Orchestral Musicians

2013 ◽  
Vol 38 (2) ◽  
pp. 223-234 ◽  
Author(s):  
Małgorzata Pawlaczyk-Łuszczyńska ◽  
Małgorzata Zamojska ◽  
Adam Dudarewicz ◽  
Kamil Zaborowski
Keyword(s):  
Hearing Loss ◽  
High Frequency ◽  
Noise Exposure ◽  
Hearing Threshold ◽  
Noise Induced Hearing Loss ◽  
Occupational Risk Factors ◽  
Threshold Levels ◽  
Exposed Population ◽  
Orchestral Musicians ◽  
The Impact

Abstract The overall purpose of this study was to assess hearing status in professional orchestral musicians. Standard pure-tone audiometry (PTA) and transient-evoked otoacoustic emissions (TEOAEs) were per- formed in 126 orchestral musicians. Occupational and non-occupational risk factors for noise-induced hearing loss (NIHL) were identified in questionnaire inquiry. Data on sound pressure levels produced by various groups of instruments were also collected and analyzed. Measured hearing threshold levels (HTLs) were compared with the theoretical predictions calculated according to ISO 1999 (1990). Musicians were exposed to excessive sound at weekly noise exposure levels of for 81-100 dB (mean: 86.6±4.0 dB) for 5-48 years (mean: 24.0±10.7 years). Most of them (95%) had hearing corresponds to grade 0 of hearing impairment (mean hearing threshold level at 500, 1000, 2000 and 4000 Hz lower than 25 dB). However, high frequency notched audiograms typical for noise-induced hearing loss were found in 35% of cases. Simultaneously, about 35% of audiograms showed typical for NIHL high frequency notches (mainly occurring at 6000 Hz). When analyzing the impact of age, gender and noise exposure on hearing test results both PTA and TEOAE consistently showed better hearing in females vs. males, younger vs. older musicians. But higher exposure to orchestral noise was not associated with poorer hearing tests results. The musician’s audiometric hearing threshold levels were poorer than equivalent non-noise-exposed population and better (at 3000 and 4000 Hz) than expected for noise-exposed population according to ISO 1999 (1990). Thus, music impairs hearing of orchestral musicians, but less than expected from noise exposure.

The effect of altitude on absolute hearing threshold levels

1982 ◽  
Author(s):  
I. B. Mekjavic ◽  
D. Sinclair ◽  
D. Steele ◽  
N. S. Longridge
Keyword(s):  
Hearing Threshold ◽  
Threshold Levels

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.

Ototoxicity of trichloroethylene in concentrations relevant for the working environment

2008 ◽  
Vol 27 (3) ◽  
pp. 195-200 ◽  
Author(s):  
A Vyskocil ◽  
T Leroux ◽  
G Truchon ◽  
F Lemay ◽  
F Gagnon ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Convincing Evidence ◽  
Working Environment ◽  
Exposure Limits ◽  
Additive Interaction ◽  
Animal Data ◽  
Short Term Exposure ◽  
Adverse Effect Level ◽  
Effect Level ◽  
Permissible Exposure Limits

Organic solvents can cause hearing loss themselves or promote noise-induced hearing loss. The objective of this study was to review the literature on the effects of low-level exposure to trichloroethylene on the auditory system and consider its relevance for the occupational settings. Both human and animal investigations were evaluated only for realistic exposure concentrations based on the Quebec permissible exposure limits: 50 ppm 8-h time-weighed average exposure value (TWAEV) and 200 ppm short-term exposure value (STEV). In humans, the upper limit for considering ototoxicity data relevant to the occupational exposure situation was set at the STEV. Animal data were evaluated only for exposure concentrations up to 100 times the TWAEV. There is no convincing evidence of trichloroethylene-induced hearing losses in workers. In rats, trichloroethylene affects the auditory function mainly in the cochlear mid- to high-frequency range with a lowest observed adverse effect level (LOAEL) of 2000 ppm. No studies on ototoxic interaction after combined exposure to noise and trichloroethylene were identified in humans. In rats, supra-additive interaction was reported. Further studies with sufficient data on the trichloroethylene exposure of workers are necessary to make a definitive conclusion. In the interim, we recommend considering trichloroethylene as an ototoxic agent.

scholarly journals Quantitative Microbial Risk Assessment for Workers Exposed to Bioaerosol in Wastewater Treatment Plants Aimed at the Choice and Setup of Safety Measures

2018 ◽  
Vol 15 (7) ◽  
pp. 1490 ◽  
Author(s):  
Annalaura Carducci ◽  
Gabriele Donzelli ◽  
Lorenzo Cioni ◽  
Ileana Federigi ◽  
Roberto Lombardi ◽  
...  
Keyword(s):  
Risk Assessment ◽  
Sensitivity Analysis ◽  
Wastewater Treatment ◽  
Health Risk ◽  
Average Risk ◽  
Quantitative Microbial Risk Assessment ◽  
Exposure Limits ◽  
Microbial Risk Assessment ◽  
Microbial Risk ◽  
The Impact

Biological risk assessment in occupational settings currently is based on either qualitative or semiquantitative analysis. In this study, a quantitative microbial risk assessment (QMRA) has been applied to estimate the human adenovirus (HAdV) health risk due to bioaerosol exposure in a wastewater treatment plant (WWTP). A stochastic QMRA model was developed considering HAdV as the index pathogen, using its concentrations in different areas and published dose–response relationship for inhalation. A sensitivity analysis was employed to examine the impact of input parameters on health risk. The QMRA estimated a higher average risk in sewage influent and biological oxidation tanks (15.64% and 12.73% for an exposure of 3 min). Sensitivity analysis indicated HAdV concentration as a predominant factor in the estimated risk. QMRA results were used to calculate the exposure limits considering four different risk levels (one illness case per 100, 1.000, 10.000, and 100.000 workers): for 3 min exposures, we obtained 565, 170, 54, and 6 GC/m3 of HAdV. We also calculated the maximum time of exposure for each level for different areas. Our findings can be useful to better define the effectiveness of control measures, which would thus reduce the virus concentration or the exposure time.

scholarly journals Sailors and the Risk of Asbestos-Related Cancer

2021 ◽  
Vol 18 (16) ◽  
pp. 8417
Author(s):  
Richard Lemen ◽  
Philip Landrigan
Keyword(s):  
Premature Death ◽  
Epidemiologic Studies ◽  
Exposure Limits ◽  
Related Disease ◽  
Occupationally Exposed ◽  
Amphibole Asbestos ◽  
Permissible Exposure Limits ◽  
Asbestos Related Disease ◽  
Risk Of Exposure ◽  
Shipyard Workers

Sailors have long been known to experience high rates of injury, disease, and premature death. Many studies have shown asbestos-related diseases among shipyard workers, but few have examined the epidemiology of asbestos-related disease and death among asbestos-exposed sailors serving on ships at sea. Chrysotile and amphibole asbestos were used extensively in ship construction for insulation, joiner bulkhead systems, pipe coverings, boilers, machinery parts, bulkhead panels, and many other uses, and asbestos-containing ships are still in service. Sailors are at high risk of exposure to shipboard asbestos, because unlike shipyard workers and other occupationally exposed groups, sailors both work and live at their worksite, making asbestos standards and permissible exposure limits (PELs). based on an 8-hour workday inadequate to protect their health elevated risks of mesothelioma and other asbestos-related cancers have been observed among sailors through epidemiologic studies. We review these studies here.

The National Shipbuilding Research Program Welding Fume Study

2001 ◽  
Vol 17 (01) ◽  
pp. 35-39
Author(s):  
Daniel O. Chute ◽  
Bradley W. Christ
Keyword(s):  
Field Evaluation ◽  
Control Measures ◽  
Welding Fume ◽  
Control Methods ◽  
Exposure Control ◽  
Exposure Limits ◽  
Shipbuilding Industry ◽  
Worker Exposure ◽  
The Cost ◽  
The Impact

This paper presents the results of a study evaluating the impact of anticipated reductions in OSHA worker exposure limits for airborne contaminants, nickel (Ni), manganese (Mn), and hexavalent chromium (Cr6) on the shipbuilding industry. As part of the study field evaluation, air monitoring and data analysis were conducted to measure the effectiveness of a series of exposure control methods including fume extractor guns, ixed fume extraction systems, portable fume extraction systems, low fume welding wires, downdraft/backdraft tables, and fume iltration devices. Six shipyards participated in this study. The study concluded that the cost of compliance increases greatly with lower exposure limits. It was recommended that the shipbuilding industry continue to develop and evaluate feasible control measures in anticipation of revised standards.

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