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As the pandemic started in Wuhan, China, many masks for medical use were routed to the Far East. People in Taiwan, Hong Kong, Singapore, and Japan are more keen on wearing masks, as they did during the SARS epidemic, turned out to be more successful at curbing the Coronavirus pandemic. While the WHO and some media suggest that use of masks may not be effective, their evidences are usually about the misuse of masks.
With constrained supply, some advocate for DIY masks. Common garment fabrics are not that effective at blocking viruses. Dr K Kwong, a Hong Kong Chemist developed the HKMask https://diymask.site/, using cotton fabric to build a filter holder. When using paper towel (“kitchen paper” on the site) as filter, it can be rather effective.
I don’t have sewing kit or skill. So I tried to work with a bandana. Turned out I can build a rather fitting mask that can withstand frequent washes. I didn’t put it to scientific tests but I think the fit should be similar to the HKMask, and airflow feels similar to wearing a surgical mask.
In this pandemic, we are only as safe as the community in general. Stay at home as much as possible. If you have to go out, please consider protecting yourself and others with this. I’d rather leave higher standard masks like N95 for medical workers. We can only avoid catastrophe by not overloading our medical system. Curb the spread, support our fighters. Be safe!