Which? is urging manufacturers and retailers to up their game on face coverings after the consumer champion’s lab tests revealed alarming differences in the effectiveness of widely-available reusable masks.
Which? found that the best performing face coverings were able to block more than 99 per cent of potentially harmful bacterial particles from penetrating the mask material – similar to the standard of surgical masks. But the worst only managed to filter out a paltry 7 per cent – allowing up to 93 per cent to escape.
With face coverings now an essential purchase and considered important for minimising the spread of coronavirus, Which?’s latest research looked at a range of popular brands and styles of face coverings and masks, including those sold by pharmacy chains, supermarkets, high street stores and online retailers.
Scientists tested for how well they filter bacteria, how breathable they are, and how they fare after multiple washes.
Three out of the 15 face coverings Which? tested performed so poorly that they were deemed a ‘Don’t Buy’. At the bottom of the table and earning the lowest scores overall were a face covering from Termini8 sold at Lloyds Pharmacy (£2), one from Asda (£3) and one from Etiquette (£3), which is sold at Superdrug.
All were lightweight and breathable as they were made with only one layer, but this affected their ability to filter potentially harmful particles, earning each mask only one star out of five in this category.
Which? awarded two of the products tested Best Buy status. The NEQI reusable face mask (£15 for 3), which is available from retailers including Boots and Ocado as well as Bags of Ethics Great British Designer face coverings (£15 for 3), available at Asos and John Lewis, were both considered comfortably breathable, earning the full five stars in this category without compromising on filtration (four stars out of five).
The lab tests revealed that masks with multiple layers are much more effective than single layer masks at filtering particles. However, Which? found that there was a clear trade off between breathability and how effective the mask was at filtering potentially harmful particles. In fact, the fabric masks that scored five out of five for filtration were also those that scored the lowest for breathability.
These included the Firebox reusable mask (£15), which is made with double-layered polyester and uses a double filter, Maskie Loop UV Sanitized reusable Face Mask (£6), which is made of three layers, and the Smart Mask (£14), which is also made of three layers and markets itself as the number one rated face mask in the UK, which all got one star for breathability. The AB Mask (£10), which is available at Boots, also received full marks for filtration but got two stars for breathability.
If a face covering isn’t breathable, it can get damp more quickly with condensation from trapped breath and might encourage people to adjust or remove their mask, especially if they wear glasses.
The Asos (£12) and AB Mask were the only two that avoided glasses steaming up and were rated highest for glasses-wearers’ comfort, with both scoring five stars in this category.
The Which? tests also revealed that almost all of the face coverings got better at filtering particles after being washed. Face coverings were re-tested after five hot wash cycles, and most improved, due to the fibres compressing.
While reusable fabric face coverings are not designed to block ultra-fine particles such as Covid-19 like a higher-grade medical respirator mask would, they are intended to help block larger droplets and aerosols breathed out by the wearer, who may be infected but asymptomatic.
The prevailing scientific thinking is that this should help protect the wider community by minimising exhalation of virus particles in enclosed public spaces.
Which? is urging manufacturers to use these findings as a basis for improving their products, while retailers should seek to ensure they are selling products that will effectively filter out potentially harmful particles. In the meantime, the consumer champion is encouraging consumers to research the best available options for themselves and their loved ones before making a purchase.
Natalie Hitchins, Which? Head of Home Products and Services, said:
“With face coverings now such an important part of daily life, they not only need to be durable and comfortable, but also provide effective filtration from harmful particles in order to keep us and others safe.
“Our results prove that there is a huge difference in quality between reusable masks sold in stores around the country and online. We would urge manufacturers to use our findings to up their game and improve their products – Until then it is worth taking time to research the best option for yourself and your loved ones.”
