'Burnt toast' argument for keeping windows open to tackle COVID

LONDON, UNITED KINGDOM - 2021/02/10: 'Maintain A Social Distance' sign in Soho, London.
Most businesses remain shut in the UK as the nation continues to battle with the coronavirus pandemic. (Photo by Vuk Valcic/SOPA Images/LightRocket via Getty Images)
A social distancing sign in Soho, London, as England starts to ease lockdown restrictions. (Getty)

A virology expert has said people should ventilate indoor areas to stop COVID transmission by acting like they have burnt their toast.

Dr Julian Tang, consultant virologist at the Leicester Royal Infirmary and honorary associate professor in the Department of Respiratory Sciences, emphasised the importance of indoor ventilation – especially when restaurants and pubs open up to customers for indoor service.

He told Sky News: “If you think about it, if you burn your toast in the kitchen, if you open the windows and doors, the back door, it clears very quickly.

LONDON, UNITED KINGDOM - APRIL 12, 2021: Crowds fill tables in Old Compton Street in Soho, which is closed to traffic, as outdoor hospitality venues open their premises to customers after being closed for over three months under coronavirus lockdown, on 12 April, 2021 in London, England. From today the next stage of lifting lockdown restrictions goes ahead with pubs and restaurants allowed to serve food and drinks outdoors, opening of non-essential shops, hairdressers, beauty salons and gyms in England. (Photo credit should read Wiktor Szymanowicz/Barcroft Media via Getty Images)
Crowds fill tables in Old Compton Street in Soho as outdoor hospitality venues opened their premises to customers on Monday. (Getty)

“So you keep the windows open even halfway most of the time, then you can improve that ventilation rate in the indoor area and that reduces the overall airborne concentration that you can actually then reduce the risk of transmission from.

“So I think this is a really kind of addition to what people are doing, the social distancing, the masking.

“But if you’re indoors having a drink or eating, you can’t mask, you can’t maintain social distance, so the ventilation becomes much more important precautionarily.”

Watch: Pubs and hairdressers open as lockdown restrictions ease

Tang also said the “garlic-breath distance” can indicate whether someone is close enough to another person for coronavirus transmission to occur.

He added: “The way this virus transmits is really through conversational distance, within one metre.

“When you’re talking to a friend or sharing the same air as you’re listening to your friend talking, we call it the garlic-breath distance.

“So if you can smell your friend’s lunch you’re inhaling some of that air as well as any virus that’s inhaled with it.

“And this is why we say that masking is fine, social distancing is fine, but the indoor airborne environment needs to be improved and that can be done with ventilation.”

On the day that the UK government eased Covid restrictions to allow non-essential businesses such as shops, pubs, bars, gyms and hairdressers to re-open, customers are served outdoor drinks on Old Compton Street in Soho, on 12th April 2021, in London, England. (Photo by Richard Baker / In Pictures via Getty Images)
Customers are served outdoor drinks on Old Compton Street in Soho, London, on the day lockdown restrictions eased. (Getty)

Tang highlighted that coronavirus could become a seasonal virus, and said that ventilation was “a kind of backup to everything else we’re doing to maintain that degree of safety that we’re all looking for”.

Many businesses in England – including pubs and restaurants – opened up their doors on Monday for the first time in months, as part of Boris Johnson’s roadmap out of lockdown.

However, customers are only allowed to sit outside in groups, with indoor dining still prohibited until May.

Fears were raised after crowds of people were seen gathering in city centres, including London, with little social distancing.

People gather in Soho, London, where streets were closed to traffic as bars and restaurants opened for outside eating and drinking, as lockdown measures are eased across the UK. Picture date: Tuesday April 13, 2021. Photo credit should read: Matt Crossick/Empics
People gathered in Soho, London, on Monday, where streets were closed to traffic as bars and restaurants opened for outside eating and drinking, as lockdown measures are eased across. (PA Images)

Westminster City Council said it was aware of “isolated incidents of crowding” and that it was working with businesses to ensure they are operating “responsibly and safely in line with guidance”.

Lawrence Young, a virologist and professor of molecular oncology at Warwick Medical School, described “a joyous day” but warned people should remain cautious.

He said: “The current reduction in cases and hospitalisations is not only due to the success of the vaccine rollout but also the impact of lockdown in preventing virus spread.

“So while taking the opportunity to enjoy shopping and outside hospitality, we must remain cautious – the virus is still out there and very infectious."

Watch: How England will leave lockdown