Instituto Tecnológico de Rocas Ornamentales y Materiales de Construcción, INTROMAC, Campus Universidad de Extremadura, 10071 Cáceres, Spain.
Instituto Tecnológico de Rocas Ornamentales y Materiales de Construcción, INTROMAC, Campus Universidad de Extremadura, 10071 Cáceres, Spain.
Sci Total Environ. 2021 Sep 10;786:147461. doi: 10.1016/j.scitotenv.2021.147461. Epub 2021 Apr 30.
This paper presents the results of an experimental study on the acoustic efficiency of plastic surgical face masks. Since the very high number of disposable masks being used globally on a daily basis to face the Covid19 pandemic is posing new environmental risks, mainly connected to improper disposal, any possible improvements in the management of this waste stream is very important. In this work their potential use as sound porous absorber is discussed. Surgical face masks are mainly made of polypropylene fibers which show good acoustical properties. Their porous structure was studied through the measurement of some non-acoustic properties: bulk density, fiber diameter, porosity, flow resistivity and tortuosity. Moreover, the sound absorption performance of samples, made of scrapped face masks, with different thicknesses was evaluated using an impedance tube according to ISO 10534-2. The results obtained from the sound absorption spectra and two single indexes, Noise Reduction Coefficient and Sound Absorption Average showed a high sound absorption value over a frequency range of interest. Finally, the sound absorption spectra obtained for surgical face masks were compared with those obtained for fibrous materials currently used in building sector, suggesting that this fibrous waste could act as a possible substitute to traditional ones.
本文介绍了一项关于医用外科口罩隔音效率的实验研究。由于在全球范围内，为应对新冠疫情，每天都有大量的一次性口罩被使用，这带来了新的环境风险，主要与不当处理有关，因此，对这种废物处理方式进行任何可能的改进都非常重要。在这项工作中，探讨了它们作为声音多孔吸声体的潜在用途。外科口罩主要由聚丙烯纤维制成，具有良好的声学性能。通过测量一些非声学特性，如体积密度、纤维直径、孔隙率、透气阻力和曲折度，研究了其多孔结构。此外，根据 ISO 10534-2，使用阻抗管评估了由废弃口罩制成的不同厚度的样品的吸声性能。从吸声谱和两个单一指标，降噪系数和吸声平均，得到的结果表明，在感兴趣的频率范围内，口罩具有较高的吸声值。最后，将外科口罩的吸声谱与建筑行业中目前使用的纤维材料的吸声谱进行了比较，表明这种纤维废物可以作为传统纤维材料的替代品。
