Reusable cloth masks: how to sanitise them
With the progressive easing of the lockdown, and with a shortage of personal protective equipment (PPE), reusable cloth masks are set to play a vital role. CARLA B RIBEIRO examines how to clean them effectively.
Cloth face masks are a last resort and do not replace any of the other measures, such as social distancing, respiratory etiquette, hand washing and avoiding face touching. But, with the lack of PPE – surgical masks or N95 or FFP2 respirators for single use – masks sewn from fabric have become very popular.
However, misuse can lead to hazards, so it is essential to know the best way to clean them and keep them hygienic.
“A mask should be treated like a piece of underwear: wash after use,” summarises Ricardo Mexia, a doctor in the Epidemiology department of the National Institute of Health Doutor Ricardo Jorge in Portugal, who says that the mask fabric should be washable and withstand high temperatures (at least 60 °C).
This is also the temperature at which reusable masks should be sanitised, says Manuela Oliveira, assistant professor of Microbiology and Immunology at the Faculty of Veterinary Medicine in Lisbon. “Social masks should preferably be washed in a washing machine, using usual detergents and at a temperature of 60 °C.”
However, if this isn’t possible, she suggests that they “can also be washed by hand, with soap and water, in which case they must be left to soak for 20 to 30 minutes”.
Even so, she warns: “Social masks are not the best option for people belonging to high-risk groups,” who should, whenever possible, “use surgical masks”.
No alcohol, no bleach
Alcohol and bleach are often suggested as options for disinfecting masks. However, “although alcohol and bleach are effective products in the elimination of this virus, they should not be used in the cleaning of fabric masks,” because, she says, “in addition to altering the characteristics of the fabric, they may cause respiratory problems”.
She adds that the masks “must be air-dried and not in the dryer, and can be ironed”. At the end of this process, if a mask is not used immediately, “it must be stored in a clean and closed bag”.
It should also be carried in its own bag, “closed and not directly in your pocket or inside a suitcase,” notes Oliveira. “Your pockets and other bags contain many other microorganisms that we want to prevent from coming into direct contact with areas that allow them to directly enter our body, such as the mouth, nose and eyes.”
Fabric masks, even if reusable, will not last forever, and must be “replaced as soon as the fabric presents alterations or deformations that prevent it from adhering to the face”.
According to the Technological Centre of the Textile and Clothing Industries in Portugal, until April 29, 2020, 71 types of community masks manufactured by Portuguese companies had been approved, but none of them maintain their protective properties above 15 washes. With homemade masks, offering less effective protection, the frequency of replacement will depend on the quality of the fabric and elastics, but “it is expected that these types of masks will withstand about 30 washes before alterations occur”.
Regarding the materials to be used, the Technological Centre advises: “The mask should preferably consist of water-repellent fabrics – like some types of Non-Woven Fabric.” Cotton masks should include several layers of fabric, with a filter inserted between them.
Mexia adds a warning about the filter: “It will depend on the use but once damp, it loses its effectiveness.” At that point, and after washing one’s hands, the filter (which can be composed of two sheets of kitchen paper or constructed from coffee filter paper) should be replaced.
The masks can be made of printed fabrics, as long as the print work doesn’t interfere with breathability. Hand-painted masks bring their own set of rules: “The paints used should not cause irritation, or compromise breathability,” says Mexia. Oliveira agrees: “Printed fabrics should not be a problem, since fabric manufacturers already have to ensure that they do not cause allergies, but hand-painted fabrics should be avoided, because they can cause breathing problems.”
This article has been translated from Portuguese, here’s a link to the original piece.