Government ministers have been warned that the plastic face visors worn by hairdressers leaves a gap that airborne coronvirus droplets could pass through.
They are now facing calls to revise guidance to barbers and hairdressers and require them to wear face masks, as well as the visors.
Scientists are said to have raised the concerns in the latest meeting of The New and Emerging Respiratory Virus Threats Advisory Group (Nervtag) on Friday.
The issues was also discussed in a recent meeting of at least one sub-committee of the Scientific Advisory Group for Emergencies (SAGE), the Daily Telegraph reports.
Prof Mark Wilcox, a professor of medical microbiology who attends Sage and two of its sub committees, said: “I don’t think the guidance is correct and I don’t understand why visors were chosen in preference to masks.
“We have, in several settings, discussed the issue of masks versus visors and I think it would be fair to say that I am not alone in these views.
“My colleagues both in those settings and in other settings share my views.
“I’ve not come across somebody who has said that visors are the best thing.”
Dr Ben Killingley, a consultant in infectious diseases who sits on Nervtag, said: “I don’t know where it came from, where someone decided that just wearing a visor for hairdressers alone would be enough. That doesn’t make sense to me.
“A visor is primarily worn to protect workers from splashes. It does the same job as goggles, protecting the eyes. No healthcare worker would ever wear a visor without a mask.
“You would have thought for their own protection and just in case they have been infected themselves, they should be wearing a mask themselves. In my view, both to protect the hairdresser and the person coming in, just wearing a visor alone is not enough.”
Professor Peter Openshaw, a member of Nervtag, tweeted his concerns, after a haircut by a barber wearing a face shield.
“His expelled breath and droplets were directed down onto me,” Prof Openshaw tweeted. “Zero protection, I’d say.”
He added that while his own mask provided protection against possible viral droplets, it would have failed to prevent “corneal seeding”, where Covid-19 particles enter the eyes.
The concerns come after SAGE said it could not be confident that the crucial coronavirus ‘R’ rate is currently below one in England.
Boris Johnson on Friday paused the easing of lockdown as fears grow that a surge of cases in some areas of northern England could turn into a second wave.
Towns in Greater Manchester, East Lancashire and West Yorkshire have been slapped with fresh restrictions with social gatherings banned indoors and in private gardens.
Meanwhile, ministers have been warned by experts that “trade-offs”, such as the closing of pubs, could be needed for schools to fully reopen in September.