Mostafa Rahmiani-Iranshahi, Mohsen Aliabadi, R Rostam Golmohamadi, Alireza Soltanian, Mohammad Babamiri,
Volume 9, Issue 1 (Iranian Journal of Ergonomics 2021)
Abstract
Background and Objectives: Noise is known as an intruder in job environments and has non-hearing effects. The impact of noise on cognitive functions depends on the type of noise and the dose of noise exposure. This study aims to investigate the effect of noise exposure on cognitive functions and sleep quality.
Methods: This descriptive-analytical cross-sectional study was performed on 169 workers in three metal, chemical, and food industries in Hamedan in 1399. A continuous performance test was used to evaluate cognitive functions. The Petersburg questionnaire assessed participant's sleep quality. Using SVAN 971 analyzer and TES dosimeter, the level of noise exposure and the dominant frequency was measured. Data were also analyzed using linear and multiple regression in SPSS software (version 16).
Results: There is a significant difference in the level of noise exposure with changes in cognitive functions and sleep quality in the present study (P<0.001). The results of linear regression showed that there is a significant relationship between cognitive function and the level of exposure to sound (P<0.001). After identifying and determining the input variables, using multiple regression, an appropriate model was developed to predict sleep quality and sustained attention in the face of noise.
Conclusion: Based on the results of this study, predictive models with the appropriate coefficient of determination can be good models for assessing the quality of sleep and attention of people in the face of noise, which can be implemented and measured in a shorter time.
Ali Sobhani Dargah, Mohsen Aliabadi, Rostam Golmohamadi, Maryam Farhadian, Mohamad Babamiri, Shiva Mohammadjani Kumeleh,
Volume 12, Issue 4 (Iranian Journal of Ergonomics-In Press 2025)
Abstract
Objectives: The present study aimed to investigate the effect of tonal noise and background speech on neurophysiological parameters and noise annoyance based on personality characteristics.
Methods: In this experimental study, 25 male students were exposed to four scenarios of tonal noise, irrelevant speech, and broadband noise as a reference in a simulated laboratory environment. The LF/HF index and galvanic skin response were recorded before and during exposure to the noise. The level of noise annoyance was determined at the end of each test session using the noise annoyance questionnaire according to ISO 15666.
Results: Repeated measures analysis of variance (RMANOVA) indicated that the difference between the values of neurophysiological indices and noise annoyance in different noise exposure scenarios was significant (P<0.05). The effect of different tonal sound levels on galvanic skin response and noise annoyance was significant (P<0.05). In addition, the effect of 65 dB tonal sound level and 55 dB speech sound level on the LF/HF index was reported to be significant (P<0.05). Also, the effect size of 1.919 in exposure to 65 dB tonal sound level had the highest value compared to other noise exposure scenarios for the noise annoyance variable.
Conclusion: Exposure to different levels of tonal noise and irrelevant speech leads to disruption of individuals' neurophysiological parameters and noise annoyance in individuals regarding some of their characteristics and personality traits.
