Is it time to ditch cloth masks for FFP2 or next-gen alternatives? | Coronavirus

Dn the early days of the pandemic, the choice was simple: you either wore a reusable cloth mask or a disposable surgical mask. Over the months, the choice of face coverings and other forms of protection has multiplied, while the emergence of more transmissible variants has prompted some countries to impose the wearing of filter masks (FFP) in public spaces.

Although face coverings are no longer legally required in England, the government has suggested continuing to wear one in enclosed, crowded spaces where you might come into contact with people you don’t normally meet.

FFP2 masks filter out at least 94% of 0.3 micron particles – covering most virus-carrying respiratory aerosols that linger in the air – and, according to research published in Fluid physicsare generally three times more effective at filtering out larger particles, typical of those produced during speech, compared to the best three-layer cloth masks.

So is it time to ditch our cloth masks in favor of FFP2 or next-gen alternatives? And is it possible to do this without resorting to single-use masks?

Cloth masks

Reusable cloth masks aren’t meant to block ultrafine particles like virus-carrying aerosols, but they do trap larger respiratory droplets, so they’re better than nothing. They also have the advantage of being washable, ideally with soapy water. warmer than 60C (140F) – thus reducing waste.

Even though cloth masks are less effective at filtering, “given the large number of parameters involved in disease transmission, we still don’t understand how much this affects disease spread,” says Dr Joshua Robinson. , a physicist at the University of Bristol. who studied the performance of masks. “If people are looking to improve the performance of their cloth masks, then improving the facial seal in problem areas like around the nose will likely help.”

Antibacterial masks

Some FFP2 masks, such as the Cradle washable multi-use mask (pictured) or the är mask, feature a silver chloride-based coating called ViralOff, which is said to destroy 99% of virus particles in two hours. It wouldn’t sterilize incoming air, but it could reduce the risk of catching the virus on your hands and transferring it elsewhere. Because the mask coating also destroys bacteria and fungi, it can also reduce the risk of “maskne”.

Robinson points out that the quality of the filter – including the electrostatic charge on the fibers, which improves the performance of the masks – is likely to degrade over time. Cradle said its mask’s ability to filter out 0.3 micron particles fell from 98.7% to 96% after 100 hours of hand washing in a mild detergent at 40C, with line drying between both, meaning it would still meet the requirements of the FFP2 standard.

Clear Masks

Helloface was founded to help people who are deaf or hard of hearing communicate – something that conventional face masks inhibit because they hide mouth movements and other facial cues. Its transparent medical mask is presented as an alternative to surgical masks and contains antimicrobial and anti-fog elements. Although not designed to be reused, the plastic components are recyclable.

UV masks

Although you may look like Darth Vader wearing it, the UVMask is one of many masks and protective products in development that incorporates UV-C light – a wavelength that inactivates viruses by destroying their protein coating – to purify incoming and outgoing air. It hasn’t received regulatory approval yet, so it’s unclear if this concept will work – according to the US Food and Drug Administrationthere are few published data on the wavelength, dose and duration of UVC radiation required to inactivate Sars-CoV-2.

The mask also features two FFP2 filters, which will likely do all the heavy lifting, says Aaron Collins, an engineer who tests and revises masks. According to him, “you are left with only one gadget”.

Postponement of disposable masks

Although it’s not stated on the packaging, many mask experts say it’s safe to wear FFP2 disposable masks again – provided you take certain precautions: put only your own mask back on; throw it away if you have been in close or prolonged contact with an infected person, or if it shows signs of obstruction, difficulty breathing, or if the straps or mask are losing their shape – which means it no longer forms a tight seal with the face; and decontaminate it between uses. To do this, you must hang it in a clean, dry place (not on a radiator) or store it in a breathable paper bag for five to seven days, while you wear a different mask.

The US Centers for Disease Control and Prevention says N95 masks (equivalent to FFP2) “can be used multiple times under crisis capacity strategies– although he recommends replacing them after five uses. “My reuse recommendation for the general public is a total wear time of 40 hours, or if the straps or mask lose shape affecting face fit – whichever comes first,” Collins says.

Never spray alcohol or disinfectant on the masks, which could damage the fibers or damage the lungs, or put the disposable masks in the washing machine, dryer, microwave or hot oven, which could also damage the fibers. According to to research at FH Münster University in Germany, foldable FFP2 masks can be safely decontaminated by heating them in an oven at 80°C for 60 minutes, or by sealing them in a freezer bag and boiling them for 10 minutes – although the elastic straps may be damaged, so check.

Air purifiers

Air purifiers have long been used in hospital operating rooms to reduce the risk of post-operative infections, but portable units are increasingly being deployed in schools and care homes assuming that they will similarly reduce the risk of coronavirus infections. Although they have been shown to reduce the amount of virus in the air – in some cases, undetectable levels – these studies have been small and have not yet proven that air purifiers reduce the risk of infection, how much or how best to deploy them.

“They can work well, but we need [this information] to make sensible, rational and evidence-based decisions,” says Professor Alastair Hay, from the University of Bristol, who is leading a study of portable air purifiers in care homes. He emphasizes that the presence of an air purifier should not be an excuse to relax other protective measures. “If it turns out that the other behaviors are the ones that are really doing the heavy lifting, then you might end up causing harm.”