Dining bubbles are popping up everywhere, but are they safe? Experts weigh in.

By Allyson Chiu

Bubble tents. Domes. Dining pods.

Whatever you call them, the clear, igloo-like structures have started popping up in U.S. cities where colder weather threatens the outdoor dining that restaurants have turned to in their attempt to stay afloat during the coronavirus pandemic.

In Seattle, a local restaurant owner told KING-TV he spent thousands of dollars installing two large plastic domes outside his eatery that would hold one table each. Similar enclosures now line the streets of Chicago’s Fulton Market and Randolph Restaurant Row area, Eater Chicago reported, noting that the structures are made out of a material that traps heat and have controls to regulate airflow. Tent-style bubbles also have been spotted in New York City; a recent viral video showed groups of diners clustered closely around candlelit tables in individual plastic pods on the sidewalk.

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While infectious-disease experts warn that careless use of these bubbles could facilitate transmission of the coronavirus, they also say it is possible for dining in them to be relatively low-risk, as long as certain precautions are taken.

“There is no right answer to this,” said Aditya Shah, an assistant professor of infectious diseases at the Mayo Clinic in Rochester, Minn., who specializes in infection prevention and control. “But there’s various levels of risk that we have to think of before going to these spaces.”

Here are the safety measures Shah and other experts recommend to lower your chances of contracting or spreading the coronavirus if you decide to go “bubble dining.”

Know the risks and benefits

While the bubbles are physically out in the open air, enclosing people inside may be akin to “creating indoor dining outdoors,” said Wafaa El-Sadr, a professor of epidemiology and medicine at Columbia University.

The igloo structures and tents “seem to be quite tight,” El-Sadr said. “Therefore, there’s not much cross-ventilation that’s happening, and often they even will close the windows or zip up the windows and the doors of the enclosure.”

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That means it is possible for the droplets people produce when they’re talking or breathing to build up inside the bubble, said Linsey Marr, a civil and environmental engineering professor at Virginia Tech who studies airborne transmission of infectious diseases. The novel coronavirus most commonly spreads through close in-person contact, but can also be transmitted through tiny droplets and particles that hang in the air for extended periods of time, especially in poorly ventilated indoor spaces, according to the Centers for Disease Control and Prevention.

“So, imagine that someone is smoking a cigarette in one of these tents,” Marr said. “The tent is going to kind of trap the smoke in there for a bit longer than if you are at an open table.”

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On the other hand, the bubbles could be an effective way to limit the amount of exposure a group of diners has to others around them, provided it is one table per bubble, said Paul Sax, clinical director of the Division of Infectious Diseases at Brigham and Women’s Hospital in Boston.

“It keeps the group that you’re potentially exposed to while dining out much smaller,” Sax said. “From just a mathematical basis, it’s safer than dining in a restaurant, where you have, potentially, exposure to multiple other people.”

Restaurants have attempted to make indoor dining safer by requiring masks, reducing capacity and spacing out tables, but a growing body of evidence suggests it is still a high-risk activity. A recent CDC study of roughly 300 adults who tested positive for the coronavirus found that they were more than twice as likely to have eaten at a restaurant in the two weeks before getting sick compared to people who were not infected.

“The difficulty is you don’t know the ventilation” inside restaurants and bars, Sax said. “People who are dining and drinking are taking their masks off, they’re having conversations. If the noise level increases, they’re having loud conversations. And all of these things have been shown to increase the risk of spread of the virus.”

These behaviors probably occur inside dining pods, too, but the occupants are really only having prolonged, unmasked interactions with the other members of their group, Sax said.

“Clearly small spaces with poor ventilation are high risk,” he said. “But at the same time, limiting the numbers of people that you’re exposed to reduces the risk, so it’s a trade-off.”

Evaluate who you’re dining with

The level of risk a dining bubble poses largely depends on its occupants, said Erica Shenoy, associate chief of the Infection Control Unit at Massachusetts General Hospital.

“If you put 20 of your closest friends in an igloo together, then there are 20 opportunities that one person in that group is infectious,” Shenoy said. It is much safer for people to have a meal with their immediate household in a bubble tent, she said, noting that the experience would be similar to eating at home.

Marr agreed. “I would eat with my own family in one of those, but not with anyone else,” she said.

Risk also could be fairly low for people who are dining with members of their pandemic pods, which could include trusted friends who are not part of their household, El-Sadr said. People who form these groups commit to following strict safety protocols, such as mask-wearing and social distancing, when they are in public or interacting with others outside their pod.

“It is obviously safer because then you know that the individuals you are with have been also observing the public health measures” and are likely all at lower risk, she said.

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Prioritize ventilation and sanitation

Once inside the bubbles, diners should find ways to make sure there is air flow within the space, experts said.

“You don’t need to feel a breeze, but it definitely shouldn’t feel stuffy,” Marr said. “Smells shouldn’t build up in there.”

Shah of the Mayo Clinic suggested keeping at least one side of the tent open. He added that experts have consistently recommended sitting outside for meals because of the importance of ventilation.

“If there’s no ventilation, then there’s no difference between sitting outside and inside,” Shah said. “If somebody else is infected there and within six feet of you, and you’ll be breathing stale air, then you do have a chance of getting infected.”

Fans could help with ventilation, but they must be positioned correctly to avoid just moving contaminated air around the space and potentially keeping the virus in the air longer, Marr said. She suggested that fans be placed facing outward near a tent’s openings.

People should also follow public safety guidelines inside the pods, including practicing good hand hygiene and wearing their masks when they aren’t eating or drinking, experts said.

“As people are talking to each other and socializing, I think keeping a mask on is very, very important,” El-Sadr said. “I do that because I think it’s also important to protect the servers.”

After each group of diners, the surfaces inside bubbles should be sanitized using soap and water or disinfectant, Shah said. El-Sadr recommended that tents also be aired out for as long as possible, though she said there is not clear guidance on the exact amount of time.

It is critical, Shah said, that such measures are diligently practiced.

“My fear is that as time goes on, these things get a little lax,” Shah said. “Everybody’s fatigued. I’m fatigued, but these precautions need to be maintained. . . . You cannot do a worse job at it now just because you’re fatigued from it.”