Voice Research Laboratory, Faculty of Medicine and Health, D18, Susan Wakil Health Building, Camperdown Campus, The University of Sydney, Western Avenue, Sydney, NSW, 2006, Australia.
Sci Rep. 2021 Mar 11;11(1):5651. doi: 10.1038/s41598-021-85130-8.
Facemasks are essential for healthcare workers but characteristics of the voice whilst wearing this personal protective equipment are not well understood. In the present study, we compared acoustic voice measures in recordings of sixteen adults producing standardised vocal tasks with and without wearing either a surgical mask or a KN95 mask. Data were analysed for mean spectral levels at 0-1 kHz and 1-8 kHz regions, an energy ratio between 0-1 and 1-8 kHz (LH1000), harmonics-to-noise ratio (HNR), smoothed cepstral peak prominence (CPPS), and vocal intensity. In connected speech there was significant attenuation of mean spectral level at 1-8 kHz region and there was no significant change in this measure at 0-1 kHz. Mean spectral levels of vowel did not change significantly in mask-wearing conditions. LH1000 for connected speech significantly increased whilst wearing either a surgical mask or KN95 mask but no significant change in this measure was found for vowel. HNR was higher in the mask-wearing conditions than the no-mask condition. CPPS and vocal intensity did not change in mask-wearing conditions. These findings implied an attenuation effects of wearing these types of masks on the voice spectra with surgical mask showing less impact than the KN95.
口罩对于医护人员来说是必不可少的，但人们对佩戴这种个人防护设备时声音的特点还不太了解。在本研究中，我们比较了十六名成年人在佩戴或不佩戴外科口罩或 KN95 口罩时，进行标准发声任务的录音中的声学语音测量值。对 0-1kHz 和 1-8kHz 区域的平均频谱水平、0-1 和 1-8kHz 之间的能量比（LH1000）、谐波噪声比（HNR）、平滑倒谱峰 prominance（CPPS）和发声强度进行了分析。在连续语音中，1-8kHz 区域的平均频谱水平有明显的衰减，而在 0-1kHz 区域没有明显的变化。在佩戴口罩的情况下，元音的平均频谱水平没有明显变化。无论是佩戴外科口罩还是 KN95 口罩，在连续语音中 LH1000 都会显著增加，但在元音中没有发现这一测量值有显著变化。HNR 在佩戴口罩的情况下比不戴口罩的情况要高。在佩戴口罩的情况下，CPPS 和发声强度没有变化。这些发现表明，佩戴这些类型的口罩会对声音频谱产生衰减效应，而外科口罩的影响比 KN95 口罩要小。
