As the Novel Corona Virus spreads across the globe, the demand for surgical masks skyrockets. There is worldwide shortage on surgical masks. Even medical staffs face the mask shortage.
As the pandemic drags on, many people are facing the reality of running out surgical masks. If you are having trouble getting surgical masks, you may consider sterilize your mask to extend its life. As there is risk reusing surgical masks, this method should be used as last resort. If you have access to new surgical masks, you should follow the usage guidelines. If you are desperate, you may consider the sterilization way to extend the life of surgical mask. There was test conducted by the staffs at Department of Biomedical Sciences, Chung Shan Medical Univiersity, Taiwan, on sterilizing surgical masks and the surgical masks can be sterilized up to 5 times with filtration ability reduced by 7.5%.
The idea is to sterilize the mask by heat. According to WHO data, corona virus can be killed at 56°C in 15 minutes. (Reference: https://www.who.int/csr/sars/survival_2003_05_04/en/). And the test conducted by Chung Shan Medical Univiersity showed at 65°C, corona virus can be killed in 4 minutes.
For myself, I use electric oven at home for sterilization. The oven I used is Xiaomi 32-Litre Electric Oven. It is a simple oven with wide temperature setting. You can set the oven temperature from 70°C to 230°C. As we need pretty accurate temperature, I use a thermometer to measure the actual oven temperature. I set the temperature around 70-80°C and sterilize the mask for 10 minutes and leave the mask inside the oven until the oven cools down. At 70-80°C, most bacteria and viruses will be killed or become inactive.
Although the test suggested the mask can be sterilize for 5 times, I will only sterilize it for 3 times.
As I said earlier, mask sterilization should only be used as last resort. Although it is not perfect, it is much better than not wearing mask due to worldwide mask shortage.
Facebook of Department of Biomedical Sciences, Chung Shan Medical Univiersity, Taiwan: https://www.facebook.com/CSMIBMS/posts/1078986522441124/