نتایج جستجو برای: sound pressure level
تعداد نتایج: 1531055 فیلتر نتایج به سال:
Audible sound is a ubiquitous environmental factor in nature that transmits oscillatory compressional pressure through the substances. To investigate the property of the sound as a mechanical stimulus for cells, an experimental system was set up using 94.0 dB sound which transmits approximately 10 mPa pressure to the cultured cells. Based on research on mechanotransduction and ultrasound effect...
Background and Objectives: Paying attention to the comfort of the patient during hospitalization is very important. Noise pollution can exacerbate a person's illness. Additionally, if the noise pollution exceeds the threshold limit, it will have negative effects on the staff and appropriate services. The aim of this study was to identify the sources and the level of noise pollution in the emerg...
background: noise is one of the most important hazardous physical factors in industrial environments. this study aimed to determine the effects of noise exposure on serum cortisol level and some blood parameters among male workers of a steel production company. methods: this cross-sectional study was conducted on 50 male workers in a steel production company. in order to assess the changes in b...
The current exposure limits of mineworkers to physical pollutants, under the Mine Health and Safety Act3 is 85 dB LAeq,8h, with a peak sound pressure level of 135 dB(A). However, the sound pressure level (SPL) of machines is generally determined according to the methods and procedures defined in SABS-ISO 3744 under free field conditions as defined in Appendix 3 of the same standard. While SPL a...
This study has been carried out in two shoe-making factories in Tehran with the aim ofevaluating the cobined effects of noise and toluene on the workers' hearing. Sixty four workers were assigned to three groups according to their exposure to noise andtoluene. 33 were exposed to noise (group 0), 5 to toluene (group 1) and 26 to noise andtoluene (group 2).The concentration were measured in the ...
This study aimed to assess exposure to sound and the risk of noise-induced hearing loss (NIHL) in orchestral musicians. Sound pressure level was measured in 1 opera and 3 symphony orchestras; questionnaires were filled in. On the basis of that data, the risk of NIHL was assessed according to Standard No. ISO 1999:1990. Classical orchestral musicians are usually exposed to sound at equivalent co...
Introduction and Purpose: Noise pollution is one of the important environmental problems that has been on a growing trend in the recent years. This study was conducted to evaluate the level of noise pollution in Omidiyeh city, Iran. Methods: Testo 815 sound level meter was employed to quantify the sound pressure level (SPL). The measurements were conducted during 7-9 am, 12- 14 am, and 19-21 pm...
Background and Objective: A practical method for noise control in environments with different noise sources is designing an acoustic cabin for the workers. In this regard, this study aimed to assess the efficiency of the acoustic cabin in a typical turbine unit of a thermal power plant to provide acoustic comfort. Materials and Methods: Measurement of the noise level and spectrum, as well as v...
The excitatory effect of different test stimuli was quantified in a large sample of primary auditory units of the starling. In order to construct an excitation pattern, the level of excitation in many single units in response to a specific test stimulus was plotted as a function of their characteristic frequency (CF). The effects of stimulus frequency and stimulus sound-pressure level on the sh...
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