Psychophysical Research Laboratory, Turku University of Applied Sciences, Turku, Finland.
Institute of Biomedicine, and Unit of Clinical Pharmacology, Turku University Hospital, University of Turku, Turku, Finland.
Indoor Air. 2021 Jan;31(1):264-274. doi: 10.1111/ina.12733. Epub 2020 Sep 14.
Effects of noise on people depend on sound level but also on other sound properties. A systematic comparison of the stress effects of speech and noise with the same frequency content is missing. This study compared stress reactions under sound conditions speech (sound level 65 dB L ), noise (65 dB), and silence (35 dB), all having similar relative frequency contents. Fifty-nine participants were exposed to one out of three sound conditions on average for 48 minutes while performing tasks requiring concentration. Acute physiological stress was estimated by measuring stress hormone concentrations in plasma (cortisol and noradrenaline), heart rate variability (HRV), and blood pressure. Psychological stress measures were subjective noise annoyance, workload, and fatigue. Compared to silence and noise, working during speech was more annoying, loading, but less tiring, and led to elevated HRV LF/HF ratio with time. Speech also raised cortisol levels compared with silence. Although noise was more annoying, and raised cortisol levels compared with silence, working during speech was more loading and caused more physiological stress than other sound conditions. Special care should be paid to noise control in workplaces requiring concentration because already exposure to moderate sound level sounds caused clear physiological effects on people.
噪声对人的影响不仅取决于声级，还取决于其他声音特性。目前缺少对具有相同频率内容的言语和噪声应激效应的系统比较。本研究比较了在声音条件下（言语：65dB 声级；噪声：65dB；安静：35dB）的应激反应，这些声音的相对频率内容相似。59 名参与者平均在安静、噪声和言语三种声音条件下各暴露 48 分钟，同时完成需要集中注意力的任务。通过测量血浆中的应激激素浓度（皮质醇和去甲肾上腺素）、心率变异性（HRV）和血压来评估急性生理应激。心理应激的测量指标包括主观噪声烦恼、工作负荷和疲劳。与安静和噪声相比，言语条件下工作时更令人烦恼、负荷更大，但疲劳感更小，并且随着时间的推移，HRV LF/HF 比值升高。与安静相比，言语还会提高皮质醇水平。尽管噪声比安静更令人烦恼，且比安静时会引起更高的皮质醇水平，但在言语条件下工作比其他声音条件更具负荷性，会引起更明显的生理应激。在需要集中注意力的工作场所，应特别注意噪声控制，因为即使是暴露在中等水平的声音下，也会对人们产生明显的生理影响。
