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                Scientists now say they know the best material for DIY face masks.


                The coronavirus pandemic has prompted a heated debate over the efficacy of DIY masks made of materials commonly found at home. Now, a new study published in the journal Physics of Fluids on Tuesday claims to have found the optimal homemade mask design.

                冠状病毒大流行引发了一场关于自制口罩功效的激烈辩论,自制口罩的材料通常是在家里发现的。现在,周二ζ 发表在《流体物理学》杂志上的一项新研究声称,他们找到了最佳的自制口罩设计。

                Researchers compared four makeshift face-mask styles, which they considered accessible options for most: a bandanna tied over the nose and mouth; a loosely folded handkerchief; a cone-style commercial mask; and a fitted, sewn mask made of two layers of quilting fabric.



                Much to the delight of many an American grandmother, the quilt fabric performed best as a protective shield against respiratory droplets.


                “While there are a few prior studies on the effectiveness of medical-grade equipment, we don’t have a lot of information about the cloth-based coverings that are most accessible to us at present,” said study author Siddhartha Verma, assistant professor at Florida Atlantic University in a statement.

                佛罗里达大西洋大学的助教,研究作者Siddhartha Verma在一份声明中说:“虽然之前有一些关于医疗级设备有效性的研究,但我们对目前最容易获得的基于布料的覆盖物没有很多信息。”

                With mask-wearing mannequins as human stand-ins, researchers employed a smoke generator with a manual pump to mimic coughs and sneezes. A laser and camera were set up to detect and capture the path of the “respiratory droplets.”


                Without a mask, droplets from the simulated cough flew more than 8 feet and up to 12. They traveled 3 feet when the bandanna was worn; 15 inches with the folded handkerchief; and 8 inches with the surgical-grade masks.


                The stitched, two-ply quilt mask, however, halted droplets after just 2 and ? inches.


                Why quilted? The study suggests that the masks made with quilting fabric fit faces better than loosely tied material. Plus, sturdy two-ply material gives a mask an added layer of protection, other studies have shown.


                They also pointed out that a higher thread count was not commensurate with success: The bandanna had the highest thread count of other cloths used, yet was least effective.


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