Acoustical role of ear canal in exposure to the typical occupational noise levels

Abstract

Different ways are used in our ears to the best possible impedance matching achieved, and somehow the impedance mismatch that is released. These ways are the greater area of the eardrum to the oval window, and amplification actions of the middle ear ossicle, the ear canal, shoulder, head, and pinna. →What this article adds:Based on our knowledge, these amplification mechanisms have been neglected in the occupational health-related noise measurements and the hearing protection programs; thus, in this study, the effects of the external auditory canal on the total sound pressure level and sound pressure levels at different frequencies were studied. Also, 3 SSPLs that are usual in the workplaces were used in this research. The ear canal can amplify the sounds and increase the sound pressure levels. This amplification is found to be greater in men than in women. The resonance ability of the ear canal is larger in some frequencies, especially in higher frequencies. This ability of the ear canal should be considered in the workplace noise evaluations.

4th Symposium on Occupational Safety and Health Proceedings Book

“…The phenomenon of noise is complex and depends not only on its physical characteristics (such as frequency and sound pressure level) but also on the individual's physiological features. For instance, it is known that the earing canal exponentiates the sound pressure level perceived by the ear and that this occurs more in men than in women (Asady, Fuente, Pourabdian, Forouharmajd, & Shokrolahi, 2021).…”

“…General hazardous effects of noise on health include, though are not limited to, sleep disturbance (Ntlhakana, Nelson, & Khoza-Shangase, 2020), pulmonary diseases, type 2 diabetes, fatigue, distraction (Hon, Tchernikov, Fairclough, & Behar, 2020), cardiovascular problems (Asady et al, 2021;Hon et al, 2020) and hypertension (Li et al, 2019). The noise exposure was also associated in the literature with injury and accident occurrence, as the annoyance effect clouds judgment and endangers action (Hon et al, 2020;Li et al, 2019).…”