The purpose of this research is to examine the impact of industrial noise levels ranging from 74 to 76 dB—which fall below the legal limit of 80 dB—on complex physiological and psychological stress responses of workers. The study employs a multimodal approach, combining objective acoustic measurements according to the EN ISO 9612:2009 standard with the monitoring of physiological parameters, specifically galvanic skin response (GSR), blood pressure, and heart rate, complemented by subjective assessments through questionnaires. Key findings revealed that the C-weighted noise level LCEX (r = 0.67) demonstrates a stronger correlation with stress response and heart rate (r = 0.66) than the standard A-weighted filter (LAEX). Although noise explains only approximately 4% of heart rate variability (R2 ≈ 0.04), providing indirect support for the multifactorial nature of stress, subjectively, 71% of workers expressed a need for noise reduction due to accompanying symptoms such as headaches and tinnitus. The highest level of cardiovascular load was consistently recorded at workstation SZ7. The results suggest that industrial noise may represent a contributing factor to psychosocial risk even at levels below regulatory limits. The results provide indirect support for the hypothesis that low-frequency noise (LFN) components play a role in psychosocial stress, suggesting the need for further investigation using detailed spectral analysis in the prevention of industrial psychosocial diseases.
Porubčanová et al. (Wed,) studied this question.