Surgical masks still effective after 10 washes, French study finds
A recent peer-reviewed study finds that surgical facemasks still offer more protection against the spread of Covid than fabric reusable ones, even after being washed several times
Disposable surgical masks have become common in France since the beginning of the pandemic, but they are only used once and create around 40,000 tonnes of plastic waste each year Pic: Shopping King Louie / Shutterstock
Disposable surgical face masks that are usually considered to be single use maintain a high level of efficiency even after being washed up to 10 times, a new study by a consortium of French scientists has found.
Philippe Cinquin, professor of public health at the Centre Hospitalier Universitaire Grenoble Alpes and a co-author of the study, said that "a washed surgical mask still performs better than a fabric mask”.
"Surgical masks, when machine washed up to ten times, retain their compatibility with the standard that applies to them, particularly in terms of performance, filtration, breathability and also cleanliness," he told Franceinfo on Monday (October 18).
The standard, set by the French standardisation association Afnor, is 98% filtration of particles between 650 nanometres and 7 microns.
Prof Cinquin said that fabric masks only achieve up to 90% filtration for a single diameter of 3 microns.
The new study, which was published in the peer-reviewed journal Chemosphere on October 11, was based on laboratory tests carried out since spring 2020.
Prof Cinquin said that it is up to the competent authorities in France, for example the Haut conseil de la santé publique, to decide whether to recommend people to wash their surgical masks based on the latest findings.
He said that doing so could offer valuable ecological benefits, as currently “disposable masks represent 1% of all plastic waste in France”.
A report by France’s agency for the dissemination of technological information (ADIT), found that between 6.8 and 13.7 billion disposable masks have been used per year in France since the beginning of the coronavirus pandemic.
This represented 40,000 tonnes of non-recycled waste in 2020 alone. France generates approximately 3.5 million tonnes of plastic waste per year.
Another advantage of being able to wash disposable surgical masks is cutting costs.
Prof Cinquin said that surgical masks are generally cheaper than reusable fabric ones so if “they can be used up to ten times, it will have an effect on the household budget”.