I ask about only surgical masks, not respirators. I know that Pres. Trump has no medical degree, but on Mar 21 2020 he proclaimed
"We have very good liquids for doing this, sanitizing the masks, and that that's something they're starting to do more and more. They're sanitizing the masks." Stanford researchers confirm N95 masks can be sterilized and reused with virtually no loss of filtration efficiency by leaving in oven for 30 mins at 70C / 158F : COVID19
On Mar 25 2020, Stanford researchers confirm N95 masks can be sterilized and reused with virtually no loss of filtration efficiency by leaving in oven for 30 mins at 70C / 158F.
On Mar 26 2020, Duke says it has found a way to safely reuse masks worn when treating COVID-19 patients : Coronavirus
Duke Health says it will stretch its supply of specialized masks used by health care workers treating coronavirus patients by decontaminating and reusing them.
Duke will use aerosolized hydrogen peroxide to treat N95 masks at its three hospitals in Durham and Raleigh. The gas permeates the masks to kill germs, including viruses, without harming the material, Duke says.
Similarly, Hong Kong`s Ann Chiang, health experts spar over 'mask steaming' - RTHK
But in a new post on Thursday, she doubled down on her claim that it is a legitimate way for people to get round the scarcity of masks in the city.
"I want to point out that a face mask is made up of three layers. The middle layer, made of polypropylene fibre, is used to filter viruses. The melting point of polypropylene fibre is 167 degrees. It can withstand heat and be steam-sterilised," she said.
"An expert from the National Health Commission, Li Lanjuan, said the new coronavirus can be killed at 56 degrees, while microbiologist Professor Yuen Kwok-yung also said the virus easily dies at 30 degrees. Therefore, steam-sterilising face masks is not unfeasible."
I can't find official advice on re-using surgical masks, and quote the CDC that warns against attempting to sanitise for re-using respirators (that, I wrote, I wasn't asking about).
Limited re-use of N95 respirators for COVID-19 patients
Limited re-use of N95 respirators when caring for patients with COVID-19 might become necessary. However, it is unknown what the potential contribution of contact transmission is for SARS-CoV-2, and caution should be used. Re-use should be implemented according to CDC guidance. Re-use has been recommended as an option for conserving respirators during previous respiratory pathogen outbreaks and pandemics. It may also be necessary to re-use N95 respirators when caring for patients with varicella or measles, although contact transmission poses a risk to HCP who implement this practice.
Yet Face Masks for Flu? Don't Reuse Them :
There is no guaranteed safe way to reuse face masks as protection against flu in the event of a pandemic, a government panel's report concluded Thursday.
The conclusion was a mild setback to U.S. efforts to prepare for an influenza caused by the H5N1 bird flu virus or another flu pathogen. Bush administration officials asked for the report to determine whether stockpiles of surgical masks and respirators could be used multiple times to extend their reach during an emergency.
"There is currently no simple, reliable way to decontaminate these devices to enable people to use them more than once," said John C. Bailar, co-chairman of the Institute of Medicine (IOM) panel that issued the report.