The filtration of cloth is quite variable and single layers of scarf, sweatshirt and t-shirt may be in the 10 to 40 per cent range. But multiple layers increase efficiency, and modern studies have confirmed that some combinations of cloth, cotton-flannel, block more than 90 per cent of particles.
The filtration of cloth is quite variable and single layers of scarf, sweatshirt and t-shirt may be in the 10 to 40 per cent range. But multiple layers increase efficiency, and modern studies have confirmed that some combinations of cloth, cotton-flannel, block more than 90 per cent of particles.
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Evidence shows cloth masks may help against COVID-19
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